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* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
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* particular file as subject to the "Classpath" exception as provided
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*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
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* 2 along with this work; if not, write to the Free Software Foundation,
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*
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/* @test
* @summary unit tests for java.lang.invoke.MethodHandles
* @compile -source 7 -target 7 MethodHandlesTest.java
* @run junit/othervm test.java.lang.invoke.MethodHandlesTest
*/
package test.java.lang.invoke;
import java.lang.invoke.*;
import java.lang.invoke.MethodHandles.Lookup;
import java.lang.reflect.*;
import java.util.*;
import org.junit.*;
import static org.junit.Assert.*;
import static org.junit.Assume.*;
/**
*
* @author jrose
*/
public class MethodHandlesTest {
// How much output?
static int verbosity = 0;
static {
String vstr = System.getProperty("test.java.lang.invoke.MethodHandlesTest.verbosity");
if (vstr != null) verbosity = Integer.parseInt(vstr);
}
// Set this true during development if you want to fast-forward to
// a particular new, non-working test. Tests which are known to
// work (or have recently worked) test this flag and return on true.
static boolean CAN_SKIP_WORKING = false;
//static { CAN_SKIP_WORKING = true; }
// Set true to test more calls. If false, some tests are just
// lookups, without exercising the actual method handle.
static boolean DO_MORE_CALLS = true;
@Test
public void testFirst() throws Throwable {
verbosity += 9; try {
// left blank for debugging
} finally { printCounts(); verbosity -= 9; }
}
// current failures
@Test @Ignore("failure in call to makeRawRetypeOnly in ToGeneric")
public void testFail_1() throws Throwable {
// AMH.<init>: IllegalArgumentException: bad adapter (conversion=0xfffab300): adapter pushes too many parameters
testSpreadArguments(int.class, 0, 6);
}
@Test @Ignore("failure in JVM when expanding the stack using asm stub for _adapter_spread_args")
public void testFail_2() throws Throwable {
// if CONV_OP_IMPLEMENTED_MASK includes OP_SPREAD_ARGS, this crashes:
testSpreadArguments(Object.class, 0, 2);
}
@Test @Ignore("IllArgEx failure in call to ToGeneric.make")
public void testFail_3() throws Throwable {
// ToGeneric.<init>: UnsupportedOperationException: NYI: primitive parameters must follow references; entryType = (int,java.lang.Object)java.lang.Object
testSpreadArguments(int.class, 1, 2);
}
@Test @Ignore("IllArgEx failure in call to ToGeneric.make")
public void testFail_4() throws Throwable {
// ToGeneric.<init>: UnsupportedOperationException: NYI: primitive parameters must follow references; entryType = (int,java.lang.Object)java.lang.Object
testCollectArguments(int.class, 1, 2);
}
@Test @Ignore("cannot collect leading primitive types")
public void testFail_5() throws Throwable {
// ToGeneric.<init>: UnsupportedOperationException: NYI: primitive parameters must follow references; entryType = (int,java.lang.Object)java.lang.Object
testInvokers(MethodType.genericMethodType(2).changeParameterType(0, int.class));
}
@Test @Ignore("should not insert arguments beyond MethodHandlePushLimit")
public void testFail_6() throws Throwable {
// ValueConversions.varargsArray: UnsupportedOperationException: NYI: cannot form a varargs array of length 13
testInsertArguments(0, 0, MAX_ARG_INCREASE+10);
}
@Test @Ignore("permuteArguments has trouble with double slots")
public void testFail_7() throws Throwable {
testPermuteArguments(new Object[]{10, 200L},
new Class<?>[]{Integer.class, long.class},
new int[]{1,0});
testPermuteArguments(new Object[]{10, 200L, 5000L},
new Class<?>[]{Integer.class, long.class, long.class},
new int[]{2,0,1}); //rot
testPermuteArguments(new Object[]{10, 200L, 5000L},
new Class<?>[]{Integer.class, long.class, long.class},
new int[]{1,2,0}); //rot
testPermuteArguments(new Object[]{10, 200L, 5000L},
new Class<?>[]{Integer.class, long.class, long.class},
new int[]{2,1,0}); //swap
testPermuteArguments(new Object[]{10, 200L, 5000L},
new Class<?>[]{Integer.class, long.class, long.class},
new int[]{0,1,2,2}); //dup
testPermuteArguments(new Object[]{10, 200L, 5000L},
new Class<?>[]{Integer.class, long.class, long.class},
new int[]{2,0,1,2});
testPermuteArguments(new Object[]{10, 200L, 5000L},
new Class<?>[]{Integer.class, long.class, long.class},
new int[]{2,2,0,1});
testPermuteArguments(4, Integer.class, 2, long.class, 6);
}
static final int MAX_ARG_INCREASE = 3;
public MethodHandlesTest() {
}
String testName;
static int allPosTests, allNegTests;
int posTests, negTests;
@After
public void printCounts() {
if (verbosity >= 2 && (posTests | negTests) != 0) {
System.out.println();
if (posTests != 0) System.out.println("=== "+testName+": "+posTests+" positive test cases run");
if (negTests != 0) System.out.println("=== "+testName+": "+negTests+" negative test cases run");
allPosTests += posTests;
allNegTests += negTests;
posTests = negTests = 0;
}
}
void countTest(boolean positive) {
if (positive) ++posTests;
else ++negTests;
}
void countTest() { countTest(true); }
void startTest(String name) {
if (testName != null) printCounts();
if (verbosity >= 1)
System.out.println(name);
posTests = negTests = 0;
testName = name;
}
@BeforeClass
public static void setUpClass() throws Exception {
calledLog.clear();
calledLog.add(null);
nextArgVal = INITIAL_ARG_VAL;
}
@AfterClass
public static void tearDownClass() throws Exception {
int posTests = allPosTests, negTests = allNegTests;
if (verbosity >= 2 && (posTests | negTests) != 0) {
System.out.println();
if (posTests != 0) System.out.println("=== "+posTests+" total positive test cases");
if (negTests != 0) System.out.println("=== "+negTests+" total negative test cases");
}
}
static List<Object> calledLog = new ArrayList<Object>();
static Object logEntry(String name, Object... args) {
return Arrays.asList(name, Arrays.asList(args));
}
static Object called(String name, Object... args) {
Object entry = logEntry(name, args);
calledLog.add(entry);
return entry;
}
static void assertCalled(String name, Object... args) {
Object expected = logEntry(name, args);
Object actual = calledLog.get(calledLog.size() - 1);
if (expected.equals(actual) && verbosity < 9) return;
System.out.println("assertCalled "+name+":");
System.out.println("expected: "+expected);
System.out.println("actual: "+actual);
System.out.println("ex. types: "+getClasses(expected));
System.out.println("act. types: "+getClasses(actual));
assertEquals("previous method call", expected, actual);
}
static void printCalled(MethodHandle target, String name, Object... args) {
if (verbosity >= 3)
System.out.println("calling MH="+target+" to "+name+Arrays.toString(args));
}
static Object castToWrapper(Object value, Class<?> dst) {
Object wrap = null;
if (value instanceof Number)
wrap = castToWrapperOrNull(((Number)value).longValue(), dst);
if (value instanceof Character)
wrap = castToWrapperOrNull((char)(Character)value, dst);
if (wrap != null) return wrap;
return dst.cast(value);
}
static Object castToWrapperOrNull(long value, Class<?> dst) {
if (dst == int.class || dst == Integer.class)
return (int)(value);
if (dst == long.class || dst == Long.class)
return (long)(value);
if (dst == char.class || dst == Character.class)
return (char)(value);
if (dst == short.class || dst == Short.class)
return (short)(value);
if (dst == float.class || dst == Float.class)
return (float)(value);
if (dst == double.class || dst == Double.class)
return (double)(value);
if (dst == byte.class || dst == Byte.class)
return (byte)(value);
if (dst == boolean.class || dst == boolean.class)
return ((value % 29) & 1) == 0;
return null;
}
static final int ONE_MILLION = (1000*1000), // first int value
TEN_BILLION = (10*1000*1000*1000), // scale factor to reach upper 32 bits
INITIAL_ARG_VAL = ONE_MILLION << 1; // <<1 makes space for sign bit;
static long nextArgVal;
static long nextArg(boolean moreBits) {
long val = nextArgVal++;
long sign = -(val & 1); // alternate signs
val >>= 1;
if (moreBits)
// Guarantee some bits in the high word.
// In any case keep the decimal representation simple-looking,
// with lots of zeroes, so as not to make the printed decimal
// strings unnecessarily noisy.
val += (val % ONE_MILLION) * TEN_BILLION;
return val ^ sign;
}
static int nextArg() {
// Produce a 32-bit result something like ONE_MILLION+(smallint).
// Example: 1_000_042.
return (int) nextArg(false);
}
static long nextArg(Class<?> kind) {
if (kind == long.class || kind == Long.class ||
kind == double.class || kind == Double.class)
// produce a 64-bit result something like
// ((TEN_BILLION+1) * (ONE_MILLION+(smallint)))
// Example: 10_000_420_001_000_042.
return nextArg(true);
return (long) nextArg();
}
static Object randomArg(Class<?> param) {
Object wrap = castToWrapperOrNull(nextArg(param), param);
if (wrap != null) {
return wrap;
}
// import sun.invoke.util.Wrapper;
// Wrapper wrap = Wrapper.forBasicType(dst);
// if (wrap == Wrapper.OBJECT && Wrapper.isWrapperType(dst))
// wrap = Wrapper.forWrapperType(dst);
// if (wrap != Wrapper.OBJECT)
// return wrap.wrap(nextArg++);
if (param.isInterface()) {
for (Class<?> c : param.getClasses()) {
if (param.isAssignableFrom(c) && !c.isInterface())
{ param = c; break; }
}
}
if (param.isInterface() || param.isAssignableFrom(String.class))
return "#"+nextArg();
else
try {
return param.newInstance();
} catch (InstantiationException ex) {
} catch (IllegalAccessException ex) {
}
return null; // random class not Object, String, Integer, etc.
}
static Object[] randomArgs(Class<?>... params) {
Object[] args = new Object[params.length];
for (int i = 0; i < args.length; i++)
args[i] = randomArg(params[i]);
return args;
}
static Object[] randomArgs(int nargs, Class<?> param) {
Object[] args = new Object[nargs];
for (int i = 0; i < args.length; i++)
args[i] = randomArg(param);
return args;
}
static <T, E extends T> T[] array(Class<T[]> atype, E... a) {
return Arrays.copyOf(a, a.length, atype);
}
static <T> T[] cat(T[] a, T... b) {
int alen = a.length, blen = b.length;
if (blen == 0) return a;
T[] c = Arrays.copyOf(a, alen + blen);
System.arraycopy(b, 0, c, alen, blen);
return c;
}
static Integer[] boxAll(int... vx) {
Integer[] res = new Integer[vx.length];
for (int i = 0; i < res.length; i++) {
res[i] = vx[i];
}
return res;
}
static Object getClasses(Object x) {
if (x == null) return x;
if (x instanceof String) return x; // keep the name
if (x instanceof List) {
// recursively report classes of the list elements
Object[] xa = ((List)x).toArray();
for (int i = 0; i < xa.length; i++)
xa[i] = getClasses(xa[i]);
return Arrays.asList(xa);
}
return x.getClass().getSimpleName();
}
/** Return lambda(arg...[arity]) { new Object[]{ arg... } } */
static MethodHandle varargsList(int arity) {
return ValueConversions.varargsList(arity);
}
/** Return lambda(arg...[arity]) { Arrays.asList(arg...) } */
static MethodHandle varargsArray(int arity) {
return ValueConversions.varargsArray(arity);
}
static MethodHandle varargsArray(Class<?> arrayType, int arity) {
return ValueConversions.varargsArray(arrayType, arity);
}
/** Variation of varargsList, but with the given rtype. */
static MethodHandle varargsList(int arity, Class<?> rtype) {
MethodHandle list = varargsList(arity);
MethodType listType = list.type().changeReturnType(rtype);
if (List.class.isAssignableFrom(rtype) || rtype == void.class || rtype == Object.class) {
// OK
} else if (rtype.isAssignableFrom(String.class)) {
if (LIST_TO_STRING == null)
try {
LIST_TO_STRING = PRIVATE.findStatic(PRIVATE.lookupClass(), "listToString",
MethodType.methodType(String.class, List.class));
} catch (Exception ex) { throw new RuntimeException(ex); }
list = MethodHandles.filterReturnValue(list, LIST_TO_STRING);
} else if (rtype.isPrimitive()) {
if (LIST_TO_INT == null)
try {
LIST_TO_INT = PRIVATE.findStatic(PRIVATE.lookupClass(), "listToInt",
MethodType.methodType(int.class, List.class));
} catch (Exception ex) { throw new RuntimeException(ex); }
list = MethodHandles.filterReturnValue(list, LIST_TO_INT);
list = MethodHandles.explicitCastArguments(list, listType);
} else {
throw new RuntimeException("varargsList: "+rtype);
}
return list.asType(listType);
}
private static MethodHandle LIST_TO_STRING, LIST_TO_INT;
private static String listToString(List x) { return x.toString(); }
private static int listToInt(List x) { return x.toString().hashCode(); }
static MethodHandle changeArgTypes(MethodHandle target, Class<?> argType) {
return changeArgTypes(target, 0, 999, argType);
}
static MethodHandle changeArgTypes(MethodHandle target,
int beg, int end, Class<?> argType) {
MethodType targetType = target.type();
end = Math.min(end, targetType.parameterCount());
ArrayList<Class<?>> argTypes = new ArrayList<Class<?>>(targetType.parameterList());
Collections.fill(argTypes.subList(beg, end), argType);
MethodType ttype2 = MethodType.methodType(targetType.returnType(), argTypes);
return target.asType(ttype2);
}
// This lookup is good for all members in and under MethodHandlesTest.
static final Lookup PRIVATE = MethodHandles.lookup();
// This lookup is good for package-private members but not private ones.
static final Lookup PACKAGE = PackageSibling.lookup();
// This lookup is good only for public members.
static final Lookup PUBLIC = MethodHandles.publicLookup();
// Subject methods...
static class Example implements IntExample {
final String name;
public Example() { name = "Example#"+nextArg(); }
protected Example(String name) { this.name = name; }
protected Example(int x) { this(); called("protected <init>", this, x); }
@Override public String toString() { return name; }
public void v0() { called("v0", this); }
void pkg_v0() { called("pkg_v0", this); }
private void pri_v0() { called("pri_v0", this); }
public static void s0() { called("s0"); }
static void pkg_s0() { called("pkg_s0"); }
private static void pri_s0() { called("pri_s0"); }
public Object v1(Object x) { return called("v1", this, x); }
public Object v2(Object x, Object y) { return called("v2", this, x, y); }
public Object v2(Object x, int y) { return called("v2", this, x, y); }
public Object v2(int x, Object y) { return called("v2", this, x, y); }
public Object v2(int x, int y) { return called("v2", this, x, y); }
public static Object s1(Object x) { return called("s1", x); }
public static Object s2(int x) { return called("s2", x); }
public static Object s3(long x) { return called("s3", x); }
public static Object s4(int x, int y) { return called("s4", x, y); }
public static Object s5(long x, int y) { return called("s5", x, y); }
public static Object s6(int x, long y) { return called("s6", x, y); }
public static Object s7(float x, double y) { return called("s7", x, y); }
static final Lookup EXAMPLE = MethodHandles.lookup(); // for testing findSpecial
}
static final Lookup EXAMPLE = Example.EXAMPLE;
public static class PubExample extends Example {
public PubExample() { super("PubExample#"+nextArg()); }
}
static class SubExample extends Example {
@Override public void v0() { called("Sub/v0", this); }
@Override void pkg_v0() { called("Sub/pkg_v0", this); }
private SubExample(int x) { called("<init>", this, x); }
public SubExample() { super("SubExample#"+nextArg()); }
}
public static interface IntExample {
public void v0();
public static class Impl implements IntExample {
public void v0() { called("Int/v0", this); }
final String name;
public Impl() { name = "Impl#"+nextArg(); }
@Override public String toString() { return name; }
}
}
static final Object[][][] ACCESS_CASES = {
{ { false, PUBLIC }, { false, PACKAGE }, { false, PRIVATE }, { false, EXAMPLE } }, //[0]: all false
{ { false, PUBLIC }, { false, PACKAGE }, { true, PRIVATE }, { true, EXAMPLE } }, //[1]: only PRIVATE
{ { false, PUBLIC }, { true, PACKAGE }, { true, PRIVATE }, { true, EXAMPLE } }, //[2]: PUBLIC false
{ { true, PUBLIC }, { true, PACKAGE }, { true, PRIVATE }, { true, EXAMPLE } }, //[3]: all true
};
static Object[][] accessCases(Class<?> defc, String name, boolean isSpecial) {
Object[][] cases;
if (name.contains("pri_") || isSpecial) {
cases = ACCESS_CASES[1]; // PRIVATE only
} else if (name.contains("pkg_") || !Modifier.isPublic(defc.getModifiers())) {
cases = ACCESS_CASES[2]; // not PUBLIC
} else {
assertTrue(name.indexOf('_') < 0);
boolean pubc = Modifier.isPublic(defc.getModifiers());
if (pubc)
cases = ACCESS_CASES[3]; // all access levels
else
cases = ACCESS_CASES[2]; // PACKAGE but not PUBLIC
}
if (defc != Example.class && cases[cases.length-1][1] == EXAMPLE)
cases = Arrays.copyOfRange(cases, 0, cases.length-1);
return cases;
}
static Object[][] accessCases(Class<?> defc, String name) {
return accessCases(defc, name, false);
}
@Test
public void testFindStatic() throws Throwable {
if (CAN_SKIP_WORKING) return;
startTest("findStatic");
testFindStatic(PubExample.class, void.class, "s0");
testFindStatic(Example.class, void.class, "s0");
testFindStatic(Example.class, void.class, "pkg_s0");
testFindStatic(Example.class, void.class, "pri_s0");
testFindStatic(Example.class, Object.class, "s1", Object.class);
testFindStatic(Example.class, Object.class, "s2", int.class);
testFindStatic(Example.class, Object.class, "s3", long.class);
testFindStatic(Example.class, Object.class, "s4", int.class, int.class);
testFindStatic(Example.class, Object.class, "s5", long.class, int.class);
testFindStatic(Example.class, Object.class, "s6", int.class, long.class);
testFindStatic(Example.class, Object.class, "s7", float.class, double.class);
testFindStatic(false, PRIVATE, Example.class, void.class, "bogus");
}
void testFindStatic(Class<?> defc, Class<?> ret, String name, Class<?>... params) throws Throwable {
for (Object[] ac : accessCases(defc, name)) {
testFindStatic((Boolean)ac[0], (Lookup)ac[1], defc, ret, name, params);
}
}
void testFindStatic(Lookup lookup, Class<?> defc, Class<?> ret, String name, Class<?>... params) throws Throwable {
testFindStatic(true, lookup, defc, ret, name, params);
}
void testFindStatic(boolean positive, Lookup lookup, Class<?> defc, Class<?> ret, String name, Class<?>... params) throws Throwable {
countTest(positive);
MethodType type = MethodType.methodType(ret, params);
MethodHandle target = null;
Exception noAccess = null;
try {
if (verbosity >= 4) System.out.println("lookup via "+lookup+" of "+defc+" "+name+type);
target = lookup.in(defc).findStatic(defc, name, type);
} catch (ReflectiveOperationException ex) {
noAccess = ex;
if (name.contains("bogus"))
assertTrue(noAccess instanceof NoSuchMethodException);
else
assertTrue(noAccess instanceof IllegalAccessException);
}
if (verbosity >= 3)
System.out.println("findStatic "+lookup+": "+defc.getName()+"."+name+"/"+type+" => "+target
+(noAccess == null ? "" : " !! "+noAccess));
if (positive && noAccess != null) throw noAccess;
assertEquals(positive ? "positive test" : "negative test erroneously passed", positive, target != null);
if (!positive) return; // negative test failed as expected
assertEquals(type, target.type());
assertNameStringContains(target, name);
if (!DO_MORE_CALLS && lookup != PRIVATE) return;
Object[] args = randomArgs(params);
printCalled(target, name, args);
target.invokeWithArguments(args);
assertCalled(name, args);
if (verbosity >= 1)
System.out.print(':');
}
static final boolean DEBUG_METHOD_HANDLE_NAMES = Boolean.getBoolean("java.lang.invoke.MethodHandle.DEBUG_NAMES");
// rough check of name string
static void assertNameStringContains(MethodHandle x, String s) {
if (!DEBUG_METHOD_HANDLE_NAMES) {
// ignore s
assertEquals("MethodHandle"+x.type(), x.toString());
return;
}
if (x.toString().contains(s)) return;
assertEquals(s, x);
}
@Test
public void testFindVirtual() throws Throwable {
if (CAN_SKIP_WORKING) return;
startTest("findVirtual");
testFindVirtual(Example.class, void.class, "v0");
testFindVirtual(Example.class, void.class, "pkg_v0");
testFindVirtual(Example.class, void.class, "pri_v0");
testFindVirtual(Example.class, Object.class, "v1", Object.class);
testFindVirtual(Example.class, Object.class, "v2", Object.class, Object.class);
testFindVirtual(Example.class, Object.class, "v2", Object.class, int.class);
testFindVirtual(Example.class, Object.class, "v2", int.class, Object.class);
testFindVirtual(Example.class, Object.class, "v2", int.class, int.class);
testFindVirtual(false, PRIVATE, Example.class, Example.class, void.class, "bogus");
// test dispatch
testFindVirtual(SubExample.class, SubExample.class, void.class, "Sub/v0");
testFindVirtual(SubExample.class, Example.class, void.class, "Sub/v0");
testFindVirtual(SubExample.class, IntExample.class, void.class, "Sub/v0");
testFindVirtual(SubExample.class, SubExample.class, void.class, "Sub/pkg_v0");
testFindVirtual(SubExample.class, Example.class, void.class, "Sub/pkg_v0");
testFindVirtual(Example.class, IntExample.class, void.class, "v0");
testFindVirtual(IntExample.Impl.class, IntExample.class, void.class, "Int/v0");
}
void testFindVirtual(Class<?> defc, Class<?> ret, String name, Class<?>... params) throws Throwable {
Class<?> rcvc = defc;
testFindVirtual(rcvc, defc, ret, name, params);
}
void testFindVirtual(Class<?> rcvc, Class<?> defc, Class<?> ret, String name, Class<?>... params) throws Throwable {
for (Object[] ac : accessCases(defc, name)) {
testFindVirtual((Boolean)ac[0], (Lookup)ac[1], rcvc, defc, ret, name, params);
}
}
void testFindVirtual(Lookup lookup, Class<?> rcvc, Class<?> defc, Class<?> ret, String name, Class<?>... params) throws Throwable {
testFindVirtual(true, lookup, rcvc, defc, ret, name, params);
}
void testFindVirtual(boolean positive, Lookup lookup, Class<?> rcvc, Class<?> defc, Class<?> ret, String name, Class<?>... params) throws Throwable {
countTest(positive);
String methodName = name.substring(1 + name.indexOf('/')); // foo/bar => foo
MethodType type = MethodType.methodType(ret, params);
MethodHandle target = null;
Exception noAccess = null;
try {
if (verbosity >= 4) System.out.println("lookup via "+lookup+" of "+defc+" "+name+type);
target = lookup.in(defc).findVirtual(defc, methodName, type);
} catch (ReflectiveOperationException ex) {
noAccess = ex;
if (name.contains("bogus"))
assertTrue(noAccess instanceof NoSuchMethodException);
else
assertTrue(noAccess instanceof IllegalAccessException);
}
if (verbosity >= 3)
System.out.println("findVirtual "+lookup+": "+defc.getName()+"."+name+"/"+type+" => "+target
+(noAccess == null ? "" : " !! "+noAccess));
if (positive && noAccess != null) throw noAccess;
assertEquals(positive ? "positive test" : "negative test erroneously passed", positive, target != null);
if (!positive) return; // negative test failed as expected
Class<?>[] paramsWithSelf = cat(array(Class[].class, (Class)defc), params);
MethodType typeWithSelf = MethodType.methodType(ret, paramsWithSelf);
assertEquals(typeWithSelf, target.type());
assertNameStringContains(target, methodName);
if (!DO_MORE_CALLS && lookup != PRIVATE) return;
Object[] argsWithSelf = randomArgs(paramsWithSelf);
if (rcvc != defc) argsWithSelf[0] = randomArg(rcvc);
printCalled(target, name, argsWithSelf);
target.invokeWithArguments(argsWithSelf);
assertCalled(name, argsWithSelf);
if (verbosity >= 1)
System.out.print(':');
}
@Test
public void testFindSpecial() throws Throwable {
if (CAN_SKIP_WORKING) return;
startTest("findSpecial");
testFindSpecial(SubExample.class, Example.class, void.class, "v0");
testFindSpecial(SubExample.class, Example.class, void.class, "pkg_v0");
// Do some negative testing:
testFindSpecial(false, EXAMPLE, SubExample.class, Example.class, void.class, "bogus");
testFindSpecial(false, PRIVATE, SubExample.class, Example.class, void.class, "bogus");
for (Lookup lookup : new Lookup[]{ PRIVATE, EXAMPLE, PACKAGE, PUBLIC }) {
testFindSpecial(false, lookup, Object.class, Example.class, void.class, "v0");
testFindSpecial(false, lookup, SubExample.class, Example.class, void.class, "<init>", int.class);
testFindSpecial(false, lookup, SubExample.class, Example.class, void.class, "s0");
}
}
void testFindSpecial(Class<?> specialCaller,
Class<?> defc, Class<?> ret, String name, Class<?>... params) throws Throwable {
testFindSpecial(true, EXAMPLE, specialCaller, defc, ret, name, params);
testFindSpecial(true, PRIVATE, specialCaller, defc, ret, name, params);
testFindSpecial(false, PACKAGE, specialCaller, defc, ret, name, params);
testFindSpecial(false, PUBLIC, specialCaller, defc, ret, name, params);
}
void testFindSpecial(boolean positive, Lookup lookup, Class<?> specialCaller,
Class<?> defc, Class<?> ret, String name, Class<?>... params) throws Throwable {
countTest(positive);
MethodType type = MethodType.methodType(ret, params);
MethodHandle target = null;
Exception noAccess = null;
try {
if (verbosity >= 4) System.out.println("lookup via "+lookup+" of "+defc+" "+name+type);
if (verbosity >= 5) System.out.println(" lookup => "+lookup.in(specialCaller));
target = lookup.in(specialCaller).findSpecial(defc, name, type, specialCaller);
} catch (ReflectiveOperationException ex) {
noAccess = ex;
if (name.contains("bogus"))
assertTrue(noAccess instanceof NoSuchMethodException);
else
assertTrue(noAccess instanceof IllegalAccessException);
}
if (verbosity >= 3)
System.out.println("findSpecial from "+specialCaller.getName()+" to "+defc.getName()+"."+name+"/"+type+" => "+target
+(target == null ? "" : target.type())
+(noAccess == null ? "" : " !! "+noAccess));
if (positive && noAccess != null) throw noAccess;
assertEquals(positive ? "positive test" : "negative test erroneously passed", positive, target != null);
if (!positive) return; // negative test failed as expected
assertEquals(specialCaller, target.type().parameterType(0));
assertEquals(type, target.type().dropParameterTypes(0,1));
Class<?>[] paramsWithSelf = cat(array(Class[].class, (Class)specialCaller), params);
MethodType typeWithSelf = MethodType.methodType(ret, paramsWithSelf);
assertNameStringContains(target, name);
if (!DO_MORE_CALLS && lookup != PRIVATE && lookup != EXAMPLE) return;
Object[] args = randomArgs(paramsWithSelf);
printCalled(target, name, args);
target.invokeWithArguments(args);
assertCalled(name, args);
}
@Test
public void testBind() throws Throwable {
if (CAN_SKIP_WORKING) return;
startTest("bind");
testBind(Example.class, void.class, "v0");
testBind(Example.class, void.class, "pkg_v0");
testBind(Example.class, void.class, "pri_v0");
testBind(Example.class, Object.class, "v1", Object.class);
testBind(Example.class, Object.class, "v2", Object.class, Object.class);
testBind(Example.class, Object.class, "v2", Object.class, int.class);
testBind(Example.class, Object.class, "v2", int.class, Object.class);
testBind(Example.class, Object.class, "v2", int.class, int.class);
testBind(false, PRIVATE, Example.class, void.class, "bogus");
testBind(SubExample.class, void.class, "Sub/v0");
testBind(SubExample.class, void.class, "Sub/pkg_v0");
testBind(IntExample.Impl.class, void.class, "Int/v0");
}
void testBind(Class<?> defc, Class<?> ret, String name, Class<?>... params) throws Throwable {
for (Object[] ac : accessCases(defc, name)) {
testBind((Boolean)ac[0], (Lookup)ac[1], defc, ret, name, params);
}
}
void testBind(boolean positive, Lookup lookup, Class<?> defc, Class<?> ret, String name, Class<?>... params) throws Throwable {
countTest(positive);
String methodName = name.substring(1 + name.indexOf('/')); // foo/bar => foo
MethodType type = MethodType.methodType(ret, params);
Object receiver = randomArg(defc);
MethodHandle target = null;
Exception noAccess = null;
try {
if (verbosity >= 4) System.out.println("lookup via "+lookup+" of "+defc+" "+name+type);
target = lookup.in(defc).bind(receiver, methodName, type);
} catch (ReflectiveOperationException ex) {
noAccess = ex;
if (name.contains("bogus"))
assertTrue(noAccess instanceof NoSuchMethodException);
else
assertTrue(noAccess instanceof IllegalAccessException);
}
if (verbosity >= 3)
System.out.println("bind "+receiver+"."+name+"/"+type+" => "+target
+(noAccess == null ? "" : " !! "+noAccess));
if (positive && noAccess != null) throw noAccess;
assertEquals(positive ? "positive test" : "negative test erroneously passed", positive, target != null);
if (!positive) return; // negative test failed as expected
assertEquals(type, target.type());
Object[] args = randomArgs(params);
printCalled(target, name, args);
target.invokeWithArguments(args);
Object[] argsWithReceiver = cat(array(Object[].class, receiver), args);
assertCalled(name, argsWithReceiver);
if (verbosity >= 1)
System.out.print(':');
}
@Test
public void testUnreflect() throws Throwable {
if (CAN_SKIP_WORKING) return;
startTest("unreflect");
testUnreflect(Example.class, true, void.class, "s0");
testUnreflect(Example.class, true, void.class, "pkg_s0");
testUnreflect(Example.class, true, void.class, "pri_s0");
testUnreflect(Example.class, true, Object.class, "s1", Object.class);
testUnreflect(Example.class, true, Object.class, "s2", int.class);
testUnreflect(Example.class, true, Object.class, "s3", long.class);
testUnreflect(Example.class, true, Object.class, "s4", int.class, int.class);
testUnreflect(Example.class, true, Object.class, "s5", long.class, int.class);
testUnreflect(Example.class, true, Object.class, "s6", int.class, long.class);
testUnreflect(Example.class, false, void.class, "v0");
testUnreflect(Example.class, false, void.class, "pkg_v0");
testUnreflect(Example.class, false, void.class, "pri_v0");
testUnreflect(Example.class, false, Object.class, "v1", Object.class);
testUnreflect(Example.class, false, Object.class, "v2", Object.class, Object.class);
testUnreflect(Example.class, false, Object.class, "v2", Object.class, int.class);
testUnreflect(Example.class, false, Object.class, "v2", int.class, Object.class);
testUnreflect(Example.class, false, Object.class, "v2", int.class, int.class);
}
void testUnreflect(Class<?> defc, boolean isStatic, Class<?> ret, String name, Class<?>... params) throws Throwable {
for (Object[] ac : accessCases(defc, name)) {
testUnreflectMaybeSpecial(null, (Boolean)ac[0], (Lookup)ac[1], defc, (isStatic ? null : defc), ret, name, params);
}
}
void testUnreflect(Class<?> defc, Class<?> rcvc, Class<?> ret, String name, Class<?>... params) throws Throwable {
for (Object[] ac : accessCases(defc, name)) {
testUnreflectMaybeSpecial(null, (Boolean)ac[0], (Lookup)ac[1], defc, rcvc, ret, name, params);
}
}
void testUnreflectMaybeSpecial(Class<?> specialCaller,
boolean positive, Lookup lookup,
Class<?> defc, Class<?> rcvc, Class<?> ret, String name, Class<?>... params) throws Throwable {
countTest(positive);
MethodType type = MethodType.methodType(ret, params);
Method rmethod = defc.getDeclaredMethod(name, params);
MethodHandle target = null;
Exception noAccess = null;
boolean isStatic = (rcvc == null);
boolean isSpecial = (specialCaller != null);
try {
if (verbosity >= 4) System.out.println("lookup via "+lookup+" of "+defc+" "+name+type);
if (isSpecial)
target = lookup.in(specialCaller).unreflectSpecial(rmethod, specialCaller);
else
target = lookup.in(defc).unreflect(rmethod);
} catch (ReflectiveOperationException ex) {
noAccess = ex;
if (name.contains("bogus"))
assertTrue(noAccess instanceof NoSuchMethodException);
else
assertTrue(noAccess instanceof IllegalAccessException);
}
if (verbosity >= 3)
System.out.println("unreflect"+(isSpecial?"Special":"")+" "+defc.getName()+"."+name+"/"+type
+(!isSpecial ? "" : " specialCaller="+specialCaller)
+( isStatic ? "" : " receiver="+rcvc)
+" => "+target
+(noAccess == null ? "" : " !! "+noAccess));
if (positive && noAccess != null) throw noAccess;
assertEquals(positive ? "positive test" : "negative test erroneously passed", positive, target != null);
if (!positive) return; // negative test failed as expected
assertEquals(isStatic, Modifier.isStatic(rmethod.getModifiers()));
Class<?>[] paramsMaybeWithSelf = params;
if (!isStatic) {
paramsMaybeWithSelf = cat(array(Class[].class, (Class)rcvc), params);
}
MethodType typeMaybeWithSelf = MethodType.methodType(ret, paramsMaybeWithSelf);
if (isStatic) {
assertEquals(typeMaybeWithSelf, target.type());
} else {
if (isSpecial)
assertEquals(specialCaller, target.type().parameterType(0));
else
assertEquals(defc, target.type().parameterType(0));
assertEquals(typeMaybeWithSelf, target.type().changeParameterType(0, rcvc));
}
Object[] argsMaybeWithSelf = randomArgs(paramsMaybeWithSelf);
printCalled(target, name, argsMaybeWithSelf);
target.invokeWithArguments(argsMaybeWithSelf);
assertCalled(name, argsMaybeWithSelf);
if (verbosity >= 1)
System.out.print(':');
}
void testUnreflectSpecial(Class<?> defc, Class<?> rcvc, Class<?> ret, String name, Class<?>... params) throws Throwable {
for (Object[] ac : accessCases(defc, name, true)) {
Class<?> specialCaller = rcvc;
testUnreflectMaybeSpecial(specialCaller, (Boolean)ac[0], (Lookup)ac[1], defc, rcvc, ret, name, params);
}
}
@Test
public void testUnreflectSpecial() throws Throwable {
if (CAN_SKIP_WORKING) return;
startTest("unreflectSpecial");
testUnreflectSpecial(Example.class, Example.class, void.class, "v0");
testUnreflectSpecial(Example.class, SubExample.class, void.class, "v0");
testUnreflectSpecial(Example.class, Example.class, void.class, "pkg_v0");
testUnreflectSpecial(Example.class, SubExample.class, void.class, "pkg_v0");
testUnreflectSpecial(Example.class, Example.class, Object.class, "v2", int.class, int.class);
testUnreflectSpecial(Example.class, SubExample.class, Object.class, "v2", int.class, int.class);
testUnreflectMaybeSpecial(Example.class, false, PRIVATE, Example.class, Example.class, void.class, "s0");
}
public static class HasFields {
boolean fZ = false;
byte fB = (byte)'B';
short fS = (short)'S';
char fC = 'C';
int fI = 'I';
long fJ = 'J';
float fF = 'F';
double fD = 'D';
static boolean sZ = true;
static byte sB = 1+(byte)'B';
static short sS = 1+(short)'S';
static char sC = 1+'C';
static int sI = 1+'I';
static long sJ = 1+'J';
static float sF = 1+'F';
static double sD = 1+'D';
Object fL = 'L';
String fR = "R";
static Object sL = 'M';
static String sR = "S";
static final Object[][] CASES;
static {
ArrayList<Object[]> cases = new ArrayList<Object[]>();
Object types[][] = {
{'L',Object.class}, {'R',String.class},
{'I',int.class}, {'J',long.class},
{'F',float.class}, {'D',double.class},
{'Z',boolean.class}, {'B',byte.class},
{'S',short.class}, {'C',char.class},
};
HasFields fields = new HasFields();
for (Object[] t : types) {
for (int kind = 0; kind <= 1; kind++) {
boolean isStatic = (kind != 0);
char btc = (Character)t[0];
String name = (isStatic ? "s" : "f") + btc;
Class<?> type = (Class<?>) t[1];
Object value;
Field field;
try {
field = HasFields.class.getDeclaredField(name);
} catch (Exception ex) {
throw new InternalError("no field HasFields."+name);
}
try {
value = field.get(fields);
} catch (Exception ex) {
throw new InternalError("cannot fetch field HasFields."+name);
}
if (type == float.class) {
float v = 'F';
if (isStatic) v++;
assertTrue(value.equals(v));
}
assertTrue(name.equals(field.getName()));
assertTrue(type.equals(field.getType()));
assertTrue(isStatic == (Modifier.isStatic(field.getModifiers())));
cases.add(new Object[]{ field, value });
}
}
cases.add(new Object[]{ new Object[]{ false, HasFields.class, "bogus_fD", double.class }, Error.class });
cases.add(new Object[]{ new Object[]{ true, HasFields.class, "bogus_sL", Object.class }, Error.class });
CASES = cases.toArray(new Object[0][]);
}
}
static final int TEST_UNREFLECT = 1, TEST_FIND_FIELD = 2, TEST_FIND_STATIC = 3, TEST_SETTER = 0x10;
static boolean testModeMatches(int testMode, boolean isStatic) {
switch (testMode) {
case TEST_FIND_STATIC: return isStatic;
case TEST_FIND_FIELD: return !isStatic;
case TEST_UNREFLECT: return true; // unreflect matches both
}
throw new InternalError("testMode="+testMode);
}
@Test
public void testUnreflectGetter() throws Throwable {
startTest("unreflectGetter");
testGetter(TEST_UNREFLECT);
}
@Test
public void testFindGetter() throws Throwable {
startTest("findGetter");
testGetter(TEST_FIND_FIELD);
}
@Test
public void testFindStaticGetter() throws Throwable {
startTest("findStaticGetter");
testGetter(TEST_FIND_STATIC);
}
public void testGetter(int testMode) throws Throwable {
Lookup lookup = PRIVATE; // FIXME: test more lookups than this one
for (Object[] c : HasFields.CASES) {
boolean positive = (c[1] != Error.class);
testGetter(positive, lookup, c[0], c[1], testMode);
}
testGetter(true, lookup,
new Object[]{ true, System.class, "out", java.io.PrintStream.class },
System.out, testMode);
for (int isStaticN = 0; isStaticN <= 1; isStaticN++) {
testGetter(false, lookup,
new Object[]{ (isStaticN != 0), System.class, "bogus", char.class },
null, testMode);
}
}
public void testGetter(boolean positive, MethodHandles.Lookup lookup,
Object fieldRef, Object value, int testMode) throws Throwable {
testAccessor(positive, lookup, fieldRef, value, testMode);
}
public void testAccessor(boolean positive, MethodHandles.Lookup lookup,
Object fieldRef, Object value, int testMode0) throws Throwable {
boolean isGetter = ((testMode0 & TEST_SETTER) == 0);
int testMode = testMode0 & ~TEST_SETTER;
boolean isStatic;
Class<?> fclass;
String fname;
Class<?> ftype;
Field f = (fieldRef instanceof Field ? (Field)fieldRef : null);
if (f != null) {
isStatic = Modifier.isStatic(f.getModifiers());
fclass = f.getDeclaringClass();
fname = f.getName();
ftype = f.getType();
} else {
Object[] scnt = (Object[]) fieldRef;
isStatic = (Boolean) scnt[0];
fclass = (Class<?>) scnt[1];
fname = (String) scnt[2];
ftype = (Class<?>) scnt[3];
try {
f = fclass.getDeclaredField(fname);
} catch (ReflectiveOperationException ex) {
f = null;
}
}
if (!testModeMatches(testMode, isStatic)) return;
if (f == null && testMode == TEST_UNREFLECT) return;
countTest(positive);
MethodType expType;
if (isGetter)
expType = MethodType.methodType(ftype, HasFields.class);
else
expType = MethodType.methodType(void.class, HasFields.class, ftype);
if (isStatic) expType = expType.dropParameterTypes(0, 1);
Exception noAccess = null;
MethodHandle mh;
try {
switch (testMode0) {
case TEST_UNREFLECT: mh = lookup.unreflectGetter(f); break;
case TEST_FIND_FIELD: mh = lookup.findGetter(fclass, fname, ftype); break;
case TEST_FIND_STATIC: mh = lookup.findStaticGetter(fclass, fname, ftype); break;
case TEST_SETTER|
TEST_UNREFLECT: mh = lookup.unreflectSetter(f); break;
case TEST_SETTER|
TEST_FIND_FIELD: mh = lookup.findSetter(fclass, fname, ftype); break;
case TEST_SETTER|
TEST_FIND_STATIC: mh = lookup.findStaticSetter(fclass, fname, ftype); break;
default:
throw new InternalError("testMode="+testMode);
}
} catch (ReflectiveOperationException ex) {
mh = null;
noAccess = ex;
if (fname.contains("bogus"))
assertTrue(noAccess instanceof NoSuchFieldException);
else
assertTrue(noAccess instanceof IllegalAccessException);
}
if (verbosity >= 3)
System.out.println("find"+(isStatic?"Static":"")+(isGetter?"Getter":"Setter")+" "+fclass.getName()+"."+fname+"/"+ftype
+" => "+mh
+(noAccess == null ? "" : " !! "+noAccess));
if (positive && noAccess != null) throw new RuntimeException(noAccess);
assertEquals(positive ? "positive test" : "negative test erroneously passed", positive, mh != null);
if (!positive) return; // negative test failed as expected
assertEquals((isStatic ? 0 : 1)+(isGetter ? 0 : 1), mh.type().parameterCount());
assertSame(mh.type(), expType);
assertNameStringContains(mh, fname);
HasFields fields = new HasFields();
Object sawValue;
Class<?> vtype = ftype;
if (ftype != int.class) vtype = Object.class;
if (isGetter) {
mh = mh.asType(mh.type().generic()
.changeReturnType(vtype));
} else {
int last = mh.type().parameterCount() - 1;
mh = mh.asType(mh.type().generic()
.changeReturnType(void.class)
.changeParameterType(last, vtype));
}
if (f != null && f.getDeclaringClass() == HasFields.class) {
assertEquals(f.get(fields), value); // clean to start with
}
if (isGetter) {
Object expValue = value;
for (int i = 0; i <= 1; i++) {
if (isStatic) {
if (ftype == int.class)
sawValue = (int) mh.invokeExact(); // do these exactly
else
sawValue = mh.invokeExact();
} else {
if (ftype == int.class)
sawValue = (int) mh.invokeExact((Object) fields);
else
sawValue = mh.invokeExact((Object) fields);
}
assertEquals(sawValue, expValue);
if (f != null && f.getDeclaringClass() == HasFields.class
&& !Modifier.isFinal(f.getModifiers())) {
Object random = randomArg(ftype);
f.set(fields, random);
expValue = random;
} else {
break;
}
}
} else {
for (int i = 0; i <= 1; i++) {
Object putValue = randomArg(ftype);
if (isStatic) {
if (ftype == int.class)
mh.invokeExact((int)putValue); // do these exactly
else
mh.invokeExact(putValue);
} else {
if (ftype == int.class)
mh.invokeExact((Object) fields, (int)putValue);
else
mh.invokeExact((Object) fields, putValue);
}
if (f != null && f.getDeclaringClass() == HasFields.class) {
assertEquals(f.get(fields), putValue);
}
}
}
if (f != null && f.getDeclaringClass() == HasFields.class) {
f.set(fields, value); // put it back
}
}
@Test
public void testUnreflectSetter() throws Throwable {
startTest("unreflectSetter");
testSetter(TEST_UNREFLECT);
}
@Test
public void testFindSetter() throws Throwable {
startTest("findSetter");
testSetter(TEST_FIND_FIELD);
}
@Test
public void testFindStaticSetter() throws Throwable {
startTest("findStaticSetter");
testSetter(TEST_FIND_STATIC);
}
public void testSetter(int testMode) throws Throwable {
Lookup lookup = PRIVATE; // FIXME: test more lookups than this one
startTest("unreflectSetter");
for (Object[] c : HasFields.CASES) {
boolean positive = (c[1] != Error.class);
testSetter(positive, lookup, c[0], c[1], testMode);
}
for (int isStaticN = 0; isStaticN <= 1; isStaticN++) {
testSetter(false, lookup,
new Object[]{ (isStaticN != 0), System.class, "bogus", char.class },
null, testMode);
}
}
public void testSetter(boolean positive, MethodHandles.Lookup lookup,
Object fieldRef, Object value, int testMode) throws Throwable {
testAccessor(positive, lookup, fieldRef, value, testMode | TEST_SETTER);
}
@Test
public void testArrayElementGetter() throws Throwable {
startTest("arrayElementGetter");
testArrayElementGetterSetter(false);
}
@Test
public void testArrayElementSetter() throws Throwable {
startTest("arrayElementSetter");
testArrayElementGetterSetter(true);
}
public void testArrayElementGetterSetter(boolean testSetter) throws Throwable {
testArrayElementGetterSetter(new Object[10], testSetter);
testArrayElementGetterSetter(new String[10], testSetter);
testArrayElementGetterSetter(new boolean[10], testSetter);
testArrayElementGetterSetter(new byte[10], testSetter);
testArrayElementGetterSetter(new char[10], testSetter);
testArrayElementGetterSetter(new short[10], testSetter);
testArrayElementGetterSetter(new int[10], testSetter);
testArrayElementGetterSetter(new float[10], testSetter);
testArrayElementGetterSetter(new long[10], testSetter);
testArrayElementGetterSetter(new double[10], testSetter);
}
public void testArrayElementGetterSetter(Object array, boolean testSetter) throws Throwable {
countTest(true);
if (verbosity >= 2) System.out.println("array type = "+array.getClass().getComponentType().getName()+"["+Array.getLength(array)+"]");
Class<?> arrayType = array.getClass();
Class<?> elemType = arrayType.getComponentType();
MethodType expType = !testSetter
? MethodType.methodType(elemType, arrayType, int.class)
: MethodType.methodType(void.class, arrayType, int.class, elemType);
MethodHandle mh = !testSetter
? MethodHandles.arrayElementGetter(arrayType)
: MethodHandles.arrayElementSetter(arrayType);
assertSame(mh.type(), expType);
if (elemType != int.class && elemType != boolean.class) {
// FIXME: change Integer.class and (Integer) below to int.class and (int) below.
MethodType gtype = mh.type().generic().changeParameterType(1, Integer.class);
if (testSetter) gtype = gtype.changeReturnType(void.class);
mh = mh.asType(gtype);
}
Object sawValue, expValue;
List<Object> model = array2list(array);
int length = Array.getLength(array);
for (int i = 0; i < length; i++) {
// update array element
Object random = randomArg(elemType);
model.set(i, random);
if (testSetter) {
if (elemType == int.class)
mh.invokeExact((int[]) array, i, (int)random);
else if (elemType == boolean.class)
mh.invokeExact((boolean[]) array, i, (boolean)random);
else
mh.invokeExact(array, (Integer)i, random);
assertEquals(model, array2list(array));
} else {
Array.set(array, i, random);
}
if (verbosity >= 5) {
List<Object> array2list = array2list(array);
System.out.println("a["+i+"]="+random+" => "+array2list);
if (!array2list.equals(model))
System.out.println("*** != "+model);
}
// observe array element
sawValue = Array.get(array, i);
if (!testSetter) {
expValue = sawValue;
if (elemType == int.class)
sawValue = (int) mh.invokeExact((int[]) array, i);
else if (elemType == boolean.class)
sawValue = (boolean) mh.invokeExact((boolean[]) array, i);
else
sawValue = mh.invokeExact(array, (Integer)i);
assertEquals(sawValue, expValue);
assertEquals(model, array2list(array));
}
}
}
List<Object> array2list(Object array) {
int length = Array.getLength(array);
ArrayList<Object> model = new ArrayList<Object>(length);
for (int i = 0; i < length; i++)
model.add(Array.get(array, i));
return model;
}
static class Callee {
static Object id() { return called("id"); }
static Object id(Object x) { return called("id", x); }
static Object id(Object x, Object y) { return called("id", x, y); }
static Object id(Object x, Object y, Object z) { return called("id", x, y, z); }
static Object id(Object... vx) { return called("id", vx); }
static MethodHandle ofType(int n) {
return ofType(Object.class, n);
}
static MethodHandle ofType(Class<?> rtype, int n) {
if (n == -1)
return ofType(MethodType.methodType(rtype, Object[].class));
return ofType(MethodType.genericMethodType(n).changeReturnType(rtype));
}
static MethodHandle ofType(Class<?> rtype, Class<?>... ptypes) {
return ofType(MethodType.methodType(rtype, ptypes));
}
static MethodHandle ofType(MethodType type) {
Class<?> rtype = type.returnType();
String pfx = "";
if (rtype != Object.class)
pfx = rtype.getSimpleName().substring(0, 1).toLowerCase();
String name = pfx+"id";
try {
return PRIVATE.findStatic(Callee.class, name, type);
} catch (Exception ex) {
throw new RuntimeException(ex);
}
}
}
@Test
public void testConvertArguments() throws Throwable {
if (CAN_SKIP_WORKING) return;
startTest("convertArguments");
testConvert(Callee.ofType(1), null, "id", int.class);
testConvert(Callee.ofType(1), null, "id", String.class);
testConvert(Callee.ofType(1), null, "id", Integer.class);
testConvert(Callee.ofType(1), null, "id", short.class);
testConvert(Callee.ofType(1), null, "id", char.class);
testConvert(Callee.ofType(1), null, "id", byte.class);
}
void testConvert(MethodHandle id, Class<?> rtype, String name, Class<?>... params) throws Throwable {
testConvert(true, id, rtype, name, params);
}
void testConvert(boolean positive,
MethodHandle id, Class<?> rtype, String name, Class<?>... params) throws Throwable {
countTest(positive);
MethodType idType = id.type();
if (rtype == null) rtype = idType.returnType();
for (int i = 0; i < params.length; i++) {
if (params[i] == null) params[i] = idType.parameterType(i);
}
// simulate the pairwise conversion
MethodType newType = MethodType.methodType(rtype, params);
Object[] args = randomArgs(newType.parameterArray());
Object[] convArgs = args.clone();
for (int i = 0; i < args.length; i++) {
Class<?> src = newType.parameterType(i);
Class<?> dst = idType.parameterType(i);
if (src != dst)
convArgs[i] = castToWrapper(convArgs[i], dst);
}
Object convResult = id.invokeWithArguments(convArgs);
{
Class<?> dst = newType.returnType();
Class<?> src = idType.returnType();
if (src != dst)
convResult = castToWrapper(convResult, dst);
}
MethodHandle target = null;
RuntimeException error = null;
try {
target = id.asType(newType);
} catch (RuntimeException ex) {
error = ex;
}
if (verbosity >= 3)
System.out.println("convert "+id+ " to "+newType+" => "+target
+(error == null ? "" : " !! "+error));
if (positive && error != null) throw error;
assertEquals(positive ? "positive test" : "negative test erroneously passed", positive, target != null);
if (!positive) return; // negative test failed as expected
assertEquals(newType, target.type());
printCalled(target, id.toString(), args);
Object result = target.invokeWithArguments(args);
assertCalled(name, convArgs);
assertEquals(convResult, result);
if (verbosity >= 1)
System.out.print(':');
}
@Test
public void testVarargsCollector() throws Throwable {
MethodHandle vac0 = PRIVATE.findStatic(MethodHandlesTest.class, "called",
MethodType.methodType(Object.class, String.class, Object[].class));
vac0 = vac0.bindTo("vac");
MethodHandle vac = vac0.asVarargsCollector(Object[].class);
testConvert(true, vac.asType(MethodType.genericMethodType(0)), null, "vac");
testConvert(true, vac.asType(MethodType.genericMethodType(0)), null, "vac");
for (Class<?> at : new Class[] { Object.class, String.class, Integer.class }) {
testConvert(true, vac.asType(MethodType.genericMethodType(1)), null, "vac", at);
testConvert(true, vac.asType(MethodType.genericMethodType(2)), null, "vac", at, at);
}
}
@Test
public void testPermuteArguments() throws Throwable {
if (CAN_SKIP_WORKING) return;
startTest("permuteArguments");
testPermuteArguments(4, Integer.class, 2, String.class, 0);
testPermuteArguments(6, Integer.class, 0, null, 30);
//testPermuteArguments(4, Integer.class, 2, long.class, 6); // FIXME Fail_7
}
public void testPermuteArguments(int max, Class<?> type1, int t2c, Class<?> type2, int dilution) throws Throwable {
if (verbosity >= 2)
System.out.println("permuteArguments "+max+"*"+type1.getName()
+(t2c==0?"":"/"+t2c+"*"+type2.getName())
+(dilution > 0 ? " with dilution "+dilution : ""));
int t2pos = t2c == 0 ? 0 : 1;
for (int inargs = t2pos+1; inargs <= max; inargs++) {
Class<?>[] types = new Class<?>[inargs];
Arrays.fill(types, type1);
if (t2c != 0) {
// Fill in a middle range with type2:
Arrays.fill(types, t2pos, Math.min(t2pos+t2c, inargs), type2);
}
Object[] args = randomArgs(types);
int numcases = 1;
for (int outargs = 0; outargs <= max; outargs++) {
if (outargs - inargs >= MAX_ARG_INCREASE) continue;
int casStep = dilution + 1;
// Avoid some common factors:
while ((casStep > 2 && casStep % 2 == 0 && inargs % 2 == 0) ||
(casStep > 3 && casStep % 3 == 0 && inargs % 3 == 0))
casStep++;
testPermuteArguments(args, types, outargs, numcases, casStep);
numcases *= inargs;
if (dilution > 10 && outargs >= 4) {
int[] reorder = new int[outargs];
// Do some special patterns, which we probably missed.
// Replication of a single argument or argument pair.
for (int i = 0; i < inargs; i++) {
Arrays.fill(reorder, i);
testPermuteArguments(args, types, reorder);
for (int d = 1; d <= 2; d++) {
if (i + d >= inargs) continue;
for (int j = 1; j < outargs; j += 2)
reorder[j] += 1;
testPermuteArguments(args, types, reorder);
testPermuteArguments(args, types, reverse(reorder));
}
}
// Repetition of a sequence of 3 or more arguments.
for (int i = 1; i < inargs; i++) {
for (int len = 3; len <= inargs; len++) {
for (int j = 0; j < outargs; j++)
reorder[j] = (i + (j % len)) % inargs;
testPermuteArguments(args, types, reorder);
testPermuteArguments(args, types, reverse(reorder));
}
}
}
}
}
}
public void testPermuteArguments(Object[] args, Class<?>[] types,
int outargs, int numcases, int casStep) throws Throwable {
int inargs = args.length;
int[] reorder = new int[outargs];
for (int cas = 0; cas < numcases; cas += casStep) {
for (int i = 0, c = cas; i < outargs; i++) {
reorder[i] = c % inargs;
c /= inargs;
}
testPermuteArguments(args, types, reorder);
}
}
static int[] reverse(int[] reorder) {
reorder = reorder.clone();
for (int i = 0, imax = reorder.length / 2; i < imax; i++) {
int j = reorder.length - 1 - i;
int tem = reorder[i];
reorder[i] = reorder[j];
reorder[j] = tem;
}
return reorder;
}
void testPermuteArguments(Object[] args, Class<?>[] types, int[] reorder) throws Throwable {
countTest();
if (args == null && types == null) {
int max = 0;
for (int j : reorder) {
if (max < j) max = j;
}
args = randomArgs(max+1, Integer.class);
}
if (args == null) {
args = randomArgs(types);
}
if (types == null) {
types = new Class<?>[args.length];
for (int i = 0; i < args.length; i++)
types[i] = args[i].getClass();
}
int inargs = args.length, outargs = reorder.length;
assertTrue(inargs == types.length);
if (verbosity >= 3)
System.out.println("permuteArguments "+Arrays.toString(reorder));
Object[] permArgs = new Object[outargs];
Class<?>[] permTypes = new Class<?>[outargs];
for (int i = 0; i < outargs; i++) {
permArgs[i] = args[reorder[i]];
permTypes[i] = types[reorder[i]];
}
if (verbosity >= 4) {
System.out.println("in args: "+Arrays.asList(args));
System.out.println("out args: "+Arrays.asList(permArgs));
System.out.println("in types: "+Arrays.asList(types));
System.out.println("out types: "+Arrays.asList(permTypes));
}
MethodType inType = MethodType.methodType(Object.class, types);
MethodType outType = MethodType.methodType(Object.class, permTypes);
MethodHandle target = varargsList(outargs).asType(outType);
MethodHandle newTarget = MethodHandles.permuteArguments(target, inType, reorder);
if (verbosity >= 5) System.out.println("newTarget = "+newTarget);
Object result = newTarget.invokeWithArguments(args);
Object expected = Arrays.asList(permArgs);
if (!expected.equals(result)) {
System.out.println("*** failed permuteArguments "+Arrays.toString(reorder)+" types="+Arrays.asList(types));
System.out.println("in args: "+Arrays.asList(args));
System.out.println("out args: "+expected);
System.out.println("bad args: "+result);
}
assertEquals(expected, result);
}
@Test
public void testSpreadArguments() throws Throwable {
if (CAN_SKIP_WORKING) return;
startTest("spreadArguments");
for (Class<?> argType : new Class[]{Object.class, Integer.class, int.class}) {
if (verbosity >= 3)
System.out.println("spreadArguments "+argType);
// FIXME: enable _adapter_spread_args and fix Fail_2
for (int nargs = 0; nargs < 10; nargs++) {
if (argType == int.class && nargs >= 6) continue; // FIXME Fail_1
for (int pos = 0; pos < nargs; pos++) {
if (argType == int.class && pos > 0) continue; // FIXME Fail_3
testSpreadArguments(argType, pos, nargs);
}
}
}
}
public void testSpreadArguments(Class<?> argType, int pos, int nargs) throws Throwable {
countTest();
Class<?> arrayType = java.lang.reflect.Array.newInstance(argType, 0).getClass();
MethodHandle target2 = varargsArray(arrayType, nargs);
MethodHandle target = target2.asType(target2.type().generic());
if (verbosity >= 3)
System.out.println("spread into "+target2+" ["+pos+".."+nargs+"]");
Object[] args = randomArgs(target2.type().parameterArray());
// make sure the target does what we think it does:
if (pos == 0 && nargs < 5 && !argType.isPrimitive()) {
Object[] check = (Object[]) (Object) target.invokeWithArguments(args);
assertArrayEquals(args, check);
switch (nargs) {
case 0:
check = (Object[]) (Object) target.invokeExact();
assertArrayEquals(args, check);
break;
case 1:
check = (Object[]) (Object) target.invokeExact(args[0]);
assertArrayEquals(args, check);
break;
case 2:
check = (Object[]) (Object) target.invokeExact(args[0], args[1]);
assertArrayEquals(args, check);
break;
}
}
List<Class<?>> newParams = new ArrayList<Class<?>>(target2.type().parameterList());
{ // modify newParams in place
List<Class<?>> spreadParams = newParams.subList(pos, nargs);
spreadParams.clear(); spreadParams.add(arrayType);
}
MethodType newType = MethodType.methodType(arrayType, newParams);
MethodHandle result = target2.asSpreader(arrayType, nargs-pos);
assert(result.type() == newType) : Arrays.asList(result, newType);
result = result.asType(newType.generic());
Object returnValue;
if (pos == 0) {
Object args2 = ValueConversions.changeArrayType(arrayType, Arrays.copyOfRange(args, pos, args.length));
returnValue = result.invokeExact(args2);
} else {
Object[] args1 = Arrays.copyOfRange(args, 0, pos+1);
args1[pos] = ValueConversions.changeArrayType(arrayType, Arrays.copyOfRange(args, pos, args.length));
returnValue = result.invokeWithArguments(args1);
}
String argstr = Arrays.toString(args);
if (!argType.isPrimitive()) {
Object[] rv = (Object[]) returnValue;
String rvs = Arrays.toString(rv);
if (!Arrays.equals(args, rv)) {
System.out.println("method: "+result);
System.out.println("expected: "+argstr);
System.out.println("returned: "+rvs);
assertArrayEquals(args, rv);
}
} else if (argType == int.class) {
String rvs = Arrays.toString((int[]) returnValue);
if (!argstr.equals(rvs)) {
System.out.println("method: "+result);
System.out.println("expected: "+argstr);
System.out.println("returned: "+rvs);
assertEquals(argstr, rvs);
}
} else if (argType == long.class) {
String rvs = Arrays.toString((long[]) returnValue);
if (!argstr.equals(rvs)) {
System.out.println("method: "+result);
System.out.println("expected: "+argstr);
System.out.println("returned: "+rvs);
assertEquals(argstr, rvs);
}
} else {
// cannot test...
}
}
@Test
public void testCollectArguments() throws Throwable {
if (CAN_SKIP_WORKING) return;
startTest("collectArguments");
for (Class<?> argType : new Class[]{Object.class, Integer.class, int.class}) {
if (verbosity >= 3)
System.out.println("collectArguments "+argType);
for (int nargs = 0; nargs < 10; nargs++) {
for (int pos = 0; pos < nargs; pos++) {
if (argType == int.class) continue; // FIXME Fail_4
testCollectArguments(argType, pos, nargs);
}
}
}
}
public void testCollectArguments(Class<?> argType, int pos, int nargs) throws Throwable {
countTest();
// fake up a MH with the same type as the desired adapter:
MethodHandle fake = varargsArray(nargs);
fake = changeArgTypes(fake, argType);
MethodType newType = fake.type();
Object[] args = randomArgs(newType.parameterArray());
// here is what should happen:
Object[] collectedArgs = Arrays.copyOfRange(args, 0, pos+1);
collectedArgs[pos] = Arrays.copyOfRange(args, pos, args.length);
// here is the MH which will witness the collected argument tail:
MethodHandle target = varargsArray(pos+1);
target = changeArgTypes(target, 0, pos, argType);
target = changeArgTypes(target, pos, pos+1, Object[].class);
if (verbosity >= 3)
System.out.println("collect from "+Arrays.asList(args)+" ["+pos+".."+nargs+"]");
MethodHandle result = target.asCollector(Object[].class, nargs-pos).asType(newType);
Object[] returnValue = (Object[]) result.invokeWithArguments(args);
// assertTrue(returnValue.length == pos+1 && returnValue[pos] instanceof Object[]);
// returnValue[pos] = Arrays.asList((Object[]) returnValue[pos]);
// collectedArgs[pos] = Arrays.asList((Object[]) collectedArgs[pos]);
assertArrayEquals(collectedArgs, returnValue);
}
@Test
public void testInsertArguments() throws Throwable {
if (CAN_SKIP_WORKING) return;
startTest("insertArguments");
for (int nargs = 0; nargs <= 4; nargs++) {
for (int ins = 0; ins <= 4; ins++) {
if (ins > MAX_ARG_INCREASE) continue; // FIXME Fail_6
for (int pos = 0; pos <= nargs; pos++) {
testInsertArguments(nargs, pos, ins);
}
}
}
}
void testInsertArguments(int nargs, int pos, int ins) throws Throwable {
countTest();
MethodHandle target = varargsArray(nargs + ins);
Object[] args = randomArgs(target.type().parameterArray());
List<Object> resList = Arrays.asList(args);
List<Object> argsToPass = new ArrayList<Object>(resList);
List<Object> argsToInsert = argsToPass.subList(pos, pos + ins);
if (verbosity >= 3)
System.out.println("insert: "+argsToInsert+" into "+target);
MethodHandle target2 = MethodHandles.insertArguments(target, pos,
(Object[]) argsToInsert.toArray());
argsToInsert.clear(); // remove from argsToInsert
Object res2 = target2.invokeWithArguments(argsToPass);
Object res2List = Arrays.asList((Object[])res2);
if (verbosity >= 3)
System.out.println("result: "+res2List);
//if (!resList.equals(res2List))
// System.out.println("*** fail at n/p/i = "+nargs+"/"+pos+"/"+ins+": "+resList+" => "+res2List);
assertEquals(resList, res2List);
}
@Test
public void testFilterReturnValue() throws Throwable {
if (CAN_SKIP_WORKING) return;
startTest("filterReturnValue");
Class<?> classOfVCList = varargsList(1).invokeWithArguments(0).getClass();
assertTrue(List.class.isAssignableFrom(classOfVCList));
for (int nargs = 0; nargs <= 3; nargs++) {
for (Class<?> rtype : new Class[] { Object.class,
List.class,
int.class,
//byte.class, //FIXME: add this
//long.class, //FIXME: add this
CharSequence.class,
String.class }) {
testFilterReturnValue(nargs, rtype);
}
}
}
void testFilterReturnValue(int nargs, Class<?> rtype) throws Throwable {
countTest();
MethodHandle target = varargsList(nargs, rtype);
MethodHandle filter;
if (List.class.isAssignableFrom(rtype) || rtype.isAssignableFrom(List.class))
filter = varargsList(1); // add another layer of list-ness
else
filter = MethodHandles.identity(rtype);
filter = filter.asType(MethodType.methodType(target.type().returnType(), rtype));
Object[] argsToPass = randomArgs(nargs, Object.class);
if (verbosity >= 3)
System.out.println("filter "+target+" to "+rtype.getSimpleName()+" with "+filter);
MethodHandle target2 = MethodHandles.filterReturnValue(target, filter);
if (verbosity >= 4)
System.out.println("filtered target: "+target2);
// Simulate expected effect of filter on return value:
Object unfiltered = target.invokeWithArguments(argsToPass);
Object expected = filter.invokeWithArguments(unfiltered);
if (verbosity >= 4)
System.out.println("unfiltered: "+unfiltered+" : "+unfiltered.getClass().getSimpleName());
if (verbosity >= 4)
System.out.println("expected: "+expected+" : "+expected.getClass().getSimpleName());
Object result = target2.invokeWithArguments(argsToPass);
if (verbosity >= 3)
System.out.println("result: "+result+" : "+result.getClass().getSimpleName());
if (!expected.equals(result))
System.out.println("*** fail at n/rt = "+nargs+"/"+rtype.getSimpleName()+": "+Arrays.asList(argsToPass)+" => "+result+" != "+expected);
assertEquals(expected, result);
}
@Test
public void testFilterArguments() throws Throwable {
if (CAN_SKIP_WORKING) return;
startTest("filterArguments");
for (int nargs = 1; nargs <= 6; nargs++) {
for (int pos = 0; pos < nargs; pos++) {
testFilterArguments(nargs, pos);
}
}
}
void testFilterArguments(int nargs, int pos) throws Throwable {
countTest();
MethodHandle target = varargsList(nargs);
MethodHandle filter = varargsList(1);
filter = filter.asType(filter.type().generic());
Object[] argsToPass = randomArgs(nargs, Object.class);
if (verbosity >= 3)
System.out.println("filter "+target+" at "+pos+" with "+filter);
MethodHandle target2 = MethodHandles.filterArguments(target, pos, filter);
// Simulate expected effect of filter on arglist:
Object[] filteredArgs = argsToPass.clone();
filteredArgs[pos] = filter.invokeExact(filteredArgs[pos]);
List<Object> expected = Arrays.asList(filteredArgs);
Object result = target2.invokeWithArguments(argsToPass);
if (verbosity >= 3)
System.out.println("result: "+result);
if (!expected.equals(result))
System.out.println("*** fail at n/p = "+nargs+"/"+pos+": "+Arrays.asList(argsToPass)+" => "+result+" != "+expected);
assertEquals(expected, result);
}
@Test
public void testFoldArguments() throws Throwable {
if (CAN_SKIP_WORKING) return;
startTest("foldArguments");
for (int nargs = 0; nargs <= 4; nargs++) {
for (int fold = 0; fold <= nargs; fold++) {
for (int pos = 0; pos <= nargs; pos++) {
testFoldArguments(nargs, pos, fold);
}
}
}
}
void testFoldArguments(int nargs, int pos, int fold) throws Throwable {
if (pos != 0) return; // can fold only at pos=0 for now
countTest();
MethodHandle target = varargsList(1 + nargs);
MethodHandle combine = varargsList(fold).asType(MethodType.genericMethodType(fold));
List<Object> argsToPass = Arrays.asList(randomArgs(nargs, Object.class));
if (verbosity >= 3)
System.out.println("fold "+target+" with "+combine);
MethodHandle target2 = MethodHandles.foldArguments(target, combine);
// Simulate expected effect of combiner on arglist:
List<Object> expected = new ArrayList<Object>(argsToPass);
List<Object> argsToFold = expected.subList(pos, pos + fold);
if (verbosity >= 3)
System.out.println("fold: "+argsToFold+" into "+target2);
Object foldedArgs = combine.invokeWithArguments(argsToFold);
argsToFold.add(0, foldedArgs);
Object result = target2.invokeWithArguments(argsToPass);
if (verbosity >= 3)
System.out.println("result: "+result);
if (!expected.equals(result))
System.out.println("*** fail at n/p/f = "+nargs+"/"+pos+"/"+fold+": "+argsToPass+" => "+result+" != "+expected);
assertEquals(expected, result);
}
@Test
public void testDropArguments() throws Throwable {
if (CAN_SKIP_WORKING) return;
startTest("dropArguments");
for (int nargs = 0; nargs <= 4; nargs++) {
for (int drop = 1; drop <= 4; drop++) {
for (int pos = 0; pos <= nargs; pos++) {
testDropArguments(nargs, pos, drop);
}
}
}
}
void testDropArguments(int nargs, int pos, int drop) throws Throwable {
countTest();
MethodHandle target = varargsArray(nargs);
Object[] args = randomArgs(target.type().parameterArray());
MethodHandle target2 = MethodHandles.dropArguments(target, pos,
Collections.nCopies(drop, Object.class).toArray(new Class[0]));
List<Object> resList = Arrays.asList(args);
List<Object> argsToDrop = new ArrayList<Object>(resList);
for (int i = drop; i > 0; i--) {
argsToDrop.add(pos, "blort#"+i);
}
Object res2 = target2.invokeWithArguments(argsToDrop);
Object res2List = Arrays.asList((Object[])res2);
//if (!resList.equals(res2List))
// System.out.println("*** fail at n/p/d = "+nargs+"/"+pos+"/"+drop+": "+argsToDrop+" => "+res2List);
assertEquals(resList, res2List);
}
@Test
public void testInvokers() throws Throwable {
if (CAN_SKIP_WORKING) return;
startTest("exactInvoker, genericInvoker, varargsInvoker, dynamicInvoker");
// exactInvoker, genericInvoker, varargsInvoker[0..N], dynamicInvoker
Set<MethodType> done = new HashSet<MethodType>();
for (int i = 0; i <= 6; i++) {
MethodType gtype = MethodType.genericMethodType(i);
for (Class<?> argType : new Class[]{Object.class, Integer.class, int.class}) {
for (int j = -1; j < i; j++) {
MethodType type = gtype;
if (j < 0)
type = type.changeReturnType(argType);
else if (argType == void.class)
continue;
else
type = type.changeParameterType(j, argType);
if (argType.isPrimitive() && j != i-1) continue; // FIXME Fail_5
if (done.add(type))
testInvokers(type);
MethodType vtype = type.changeReturnType(void.class);
if (done.add(vtype))
testInvokers(vtype);
}
}
}
}
public void testInvokers(MethodType type) throws Throwable {
if (verbosity >= 3)
System.out.println("test invokers for "+type);
int nargs = type.parameterCount();
boolean testRetCode = type.returnType() != void.class;
MethodHandle target = PRIVATE.findStatic(MethodHandlesTest.class, "invokee",
MethodType.genericMethodType(0, true));
assertTrue(target.isVarargsCollector());
target = target.asType(type);
Object[] args = randomArgs(type.parameterArray());
List<Object> targetPlusArgs = new ArrayList<Object>(Arrays.asList(args));
targetPlusArgs.add(0, target);
int code = (Integer) invokee(args);
Object log = logEntry("invokee", args);
assertEquals(log.hashCode(), code);
assertCalled("invokee", args);
MethodHandle inv;
Object result;
// exact invoker
countTest();
calledLog.clear();
inv = MethodHandles.exactInvoker(type);
result = inv.invokeWithArguments(targetPlusArgs);
if (testRetCode) assertEquals(code, result);
assertCalled("invokee", args);
// generic invoker
countTest();
inv = MethodHandles.invoker(type);
if (nargs <= 3 && type == type.generic()) {
calledLog.clear();
switch (nargs) {
case 0:
result = inv.invokeExact(target);
break;
case 1:
result = inv.invokeExact(target, args[0]);
break;
case 2:
result = inv.invokeExact(target, args[0], args[1]);
break;
case 3:
result = inv.invokeExact(target, args[0], args[1], args[2]);
break;
}
if (testRetCode) assertEquals(code, result);
assertCalled("invokee", args);
}
calledLog.clear();
result = inv.invokeWithArguments(targetPlusArgs);
if (testRetCode) assertEquals(code, result);
assertCalled("invokee", args);
// varargs invoker #0
calledLog.clear();
inv = MethodHandles.spreadInvoker(type, 0);
if (type.returnType() == Object.class) {
result = inv.invokeExact(target, args);
} else if (type.returnType() == void.class) {
result = null; inv.invokeExact(target, args);
} else {
result = inv.invokeWithArguments(target, (Object) args);
}
if (testRetCode) assertEquals(code, result);
assertCalled("invokee", args);
if (nargs >= 1 && type == type.generic()) {
// varargs invoker #1
calledLog.clear();
inv = MethodHandles.spreadInvoker(type, 1);
result = inv.invokeExact(target, args[0], Arrays.copyOfRange(args, 1, nargs));
if (testRetCode) assertEquals(code, result);
assertCalled("invokee", args);
}
if (nargs >= 2 && type == type.generic()) {
// varargs invoker #2
calledLog.clear();
inv = MethodHandles.spreadInvoker(type, 2);
result = inv.invokeExact(target, args[0], args[1], Arrays.copyOfRange(args, 2, nargs));
if (testRetCode) assertEquals(code, result);
assertCalled("invokee", args);
}
if (nargs >= 3 && type == type.generic()) {
// varargs invoker #3
calledLog.clear();
inv = MethodHandles.spreadInvoker(type, 3);
result = inv.invokeExact(target, args[0], args[1], args[2], Arrays.copyOfRange(args, 3, nargs));
if (testRetCode) assertEquals(code, result);
assertCalled("invokee", args);
}
for (int k = 0; k <= nargs; k++) {
// varargs invoker #0..N
countTest();
calledLog.clear();
inv = MethodHandles.spreadInvoker(type, k);
MethodType expType = (type.dropParameterTypes(k, nargs)
.appendParameterTypes(Object[].class)
.insertParameterTypes(0, MethodHandle.class));
assertEquals(expType, inv.type());
List<Object> targetPlusVarArgs = new ArrayList<Object>(targetPlusArgs);
List<Object> tailList = targetPlusVarArgs.subList(1+k, 1+nargs);
Object[] tail = tailList.toArray();
tailList.clear(); tailList.add(tail);
result = inv.invokeWithArguments(targetPlusVarArgs);
if (testRetCode) assertEquals(code, result);
assertCalled("invokee", args);
}
// dynamic invoker
countTest();
CallSite site = new MutableCallSite(type);
inv = site.dynamicInvoker();
// see if we get the result of the original target:
try {
result = inv.invokeWithArguments(args);
assertTrue("should not reach here", false);
} catch (IllegalStateException ex) {
String msg = ex.getMessage();
assertTrue(msg, msg.contains("site"));
}
// set new target after invoker is created, to make sure we track target
site.setTarget(target);
calledLog.clear();
result = inv.invokeWithArguments(args);
if (testRetCode) assertEquals(code, result);
assertCalled("invokee", args);
}
static Object invokee(Object... args) {
return called("invokee", args).hashCode();
}
private static final String MISSING_ARG = "missingArg";
static Object targetIfEquals() {
return called("targetIfEquals");
}
static Object fallbackIfNotEquals() {
return called("fallbackIfNotEquals");
}
static Object targetIfEquals(Object x) {
assertEquals(x, MISSING_ARG);
return called("targetIfEquals", x);
}
static Object fallbackIfNotEquals(Object x) {
assertFalse(x.toString(), x.equals(MISSING_ARG));
return called("fallbackIfNotEquals", x);
}
static Object targetIfEquals(Object x, Object y) {
assertEquals(x, y);
return called("targetIfEquals", x, y);
}
static Object fallbackIfNotEquals(Object x, Object y) {
assertFalse(x.toString(), x.equals(y));
return called("fallbackIfNotEquals", x, y);
}
static Object targetIfEquals(Object x, Object y, Object z) {
assertEquals(x, y);
return called("targetIfEquals", x, y, z);
}
static Object fallbackIfNotEquals(Object x, Object y, Object z) {
assertFalse(x.toString(), x.equals(y));
return called("fallbackIfNotEquals", x, y, z);
}
@Test
public void testGuardWithTest() throws Throwable {
if (CAN_SKIP_WORKING) return;
startTest("guardWithTest");
for (int nargs = 0; nargs <= 3; nargs++) {
if (nargs != 2) continue; // FIXME: test more later
testGuardWithTest(nargs, Object.class);
testGuardWithTest(nargs, String.class);
}
}
void testGuardWithTest(int nargs, Class<?> argClass) throws Throwable {
countTest();
MethodHandle test = PRIVATE.findVirtual(Object.class, "equals", MethodType.methodType(boolean.class, Object.class));
MethodHandle target = PRIVATE.findStatic(MethodHandlesTest.class, "targetIfEquals", MethodType.genericMethodType(nargs));
MethodHandle fallback = PRIVATE.findStatic(MethodHandlesTest.class, "fallbackIfNotEquals", MethodType.genericMethodType(nargs));
while (test.type().parameterCount() < nargs)
test = MethodHandles.dropArguments(test, test.type().parameterCount()-1, Object.class);
while (test.type().parameterCount() > nargs)
test = MethodHandles.insertArguments(test, 0, MISSING_ARG);
if (argClass != Object.class) {
test = changeArgTypes(test, argClass);
target = changeArgTypes(target, argClass);
fallback = changeArgTypes(fallback, argClass);
}
MethodHandle mh = MethodHandles.guardWithTest(test, target, fallback);
assertEquals(target.type(), mh.type());
Object[][] argLists = {
{ },
{ "foo" }, { MISSING_ARG },
{ "foo", "foo" }, { "foo", "bar" },
{ "foo", "foo", "baz" }, { "foo", "bar", "baz" }
};
for (Object[] argList : argLists) {
if (argList.length != nargs) continue;
boolean equals;
switch (nargs) {
case 0: equals = true; break;
case 1: equals = MISSING_ARG.equals(argList[0]); break;
default: equals = argList[0].equals(argList[1]); break;
}
String willCall = (equals ? "targetIfEquals" : "fallbackIfNotEquals");
if (verbosity >= 3)
System.out.println(logEntry(willCall, argList));
Object result = mh.invokeWithArguments(argList);
assertCalled(willCall, argList);
}
}
@Test
public void testCatchException() throws Throwable {
if (CAN_SKIP_WORKING) return;
startTest("catchException");
for (int nargs = 2; nargs <= 6; nargs++) {
for (int ti = 0; ti <= 1; ti++) {
boolean throwIt = (ti != 0);
testCatchException(int.class, new ClassCastException("testing"), throwIt, nargs);
testCatchException(void.class, new java.io.IOException("testing"), throwIt, nargs);
testCatchException(String.class, new LinkageError("testing"), throwIt, nargs);
}
}
}
private static <T extends Throwable>
Object throwOrReturn(Object normal, T exception) throws T {
if (exception != null) throw exception;
return normal;
}
void testCatchException(Class<?> returnType, Throwable thrown, boolean throwIt, int nargs) throws Throwable {
countTest();
if (verbosity >= 3)
System.out.println("catchException rt="+returnType+" throw="+throwIt+" nargs="+nargs);
Class<? extends Throwable> exType = thrown.getClass();
MethodHandle throwOrReturn
= PRIVATE.findStatic(MethodHandlesTest.class, "throwOrReturn",
MethodType.methodType(Object.class, Object.class, Throwable.class));
MethodHandle thrower = throwOrReturn.asType(MethodType.genericMethodType(2));
while (thrower.type().parameterCount() < nargs)
thrower = MethodHandles.dropArguments(thrower, thrower.type().parameterCount(), Object.class);
MethodHandle catcher = varargsList(1+nargs).asType(MethodType.genericMethodType(1+nargs));
MethodHandle target = MethodHandles.catchException(thrower,
thrown.getClass(), catcher);
assertEquals(thrower.type(), target.type());
//System.out.println("catching with "+target+" : "+throwOrReturn);
Object[] args = randomArgs(nargs, Object.class);
args[1] = (throwIt ? thrown : null);
Object returned = target.invokeWithArguments(args);
//System.out.println("return from "+target+" : "+returned);
if (!throwIt) {
assertSame(args[0], returned);
} else {
List<Object> catchArgs = new ArrayList<Object>(Arrays.asList(args));
catchArgs.add(0, thrown);
assertEquals(catchArgs, returned);
}
}
@Test
public void testThrowException() throws Throwable {
if (CAN_SKIP_WORKING) return;
startTest("throwException");
testThrowException(int.class, new ClassCastException("testing"));
testThrowException(void.class, new java.io.IOException("testing"));
testThrowException(String.class, new LinkageError("testing"));
}
void testThrowException(Class<?> returnType, Throwable thrown) throws Throwable {
countTest();
Class<? extends Throwable> exType = thrown.getClass();
MethodHandle target = MethodHandles.throwException(returnType, exType);
//System.out.println("throwing with "+target+" : "+thrown);
MethodType expectedType = MethodType.methodType(returnType, exType);
assertEquals(expectedType, target.type());
target = target.asType(target.type().generic());
Throwable caught = null;
try {
Object res = target.invokeExact((Object) thrown);
fail("got "+res+" instead of throwing "+thrown);
} catch (Throwable ex) {
if (ex != thrown) {
if (ex instanceof Error) throw (Error)ex;
if (ex instanceof RuntimeException) throw (RuntimeException)ex;
}
caught = ex;
}
assertSame(thrown, caught);
}
@Test
public void testCastFailure() throws Throwable {
if (CAN_SKIP_WORKING) return;
startTest("testCastFailure");
testCastFailure("cast/argument", 11000);
testCastFailure("unbox/argument", 11000);
testCastFailure("cast/return", 11000);
testCastFailure("unbox/return", 11000);
}
static class Surprise {
public MethodHandle asMethodHandle() {
return VALUE.bindTo(this);
}
Object value(Object x) {
trace("value", x);
if (boo != null) return boo;
return x;
}
Object boo;
void boo(Object x) { boo = x; }
static void trace(String x, Object y) {
if (verbosity > 8) System.out.println(x+"="+y);
}
static Object refIdentity(Object x) { trace("ref.x", x); return x; }
static Integer boxIdentity(Integer x) { trace("box.x", x); return x; }
static int intIdentity(int x) { trace("int.x", x); return x; }
static MethodHandle VALUE, REF_IDENTITY, BOX_IDENTITY, INT_IDENTITY;
static {
try {
VALUE = PRIVATE.findVirtual(
Surprise.class, "value",
MethodType.methodType(Object.class, Object.class));
REF_IDENTITY = PRIVATE.findStatic(
Surprise.class, "refIdentity",
MethodType.methodType(Object.class, Object.class));
BOX_IDENTITY = PRIVATE.findStatic(
Surprise.class, "boxIdentity",
MethodType.methodType(Integer.class, Integer.class));
INT_IDENTITY = PRIVATE.findStatic(
Surprise.class, "intIdentity",
MethodType.methodType(int.class, int.class));
} catch (Exception ex) {
throw new RuntimeException(ex);
}
}
}
void testCastFailure(String mode, int okCount) throws Throwable {
countTest(false);
if (verbosity > 2) System.out.println("mode="+mode);
Surprise boo = new Surprise();
MethodHandle identity = Surprise.REF_IDENTITY, surprise0 = boo.asMethodHandle(), surprise = surprise0;
if (mode.endsWith("/return")) {
if (mode.equals("unbox/return")) {
// fail on return to ((Integer)surprise).intValue
surprise = surprise.asType(MethodType.methodType(int.class, Object.class));
identity = identity.asType(MethodType.methodType(int.class, Object.class));
} else if (mode.equals("cast/return")) {
// fail on return to (Integer)surprise
surprise = surprise.asType(MethodType.methodType(Integer.class, Object.class));
identity = identity.asType(MethodType.methodType(Integer.class, Object.class));
}
} else if (mode.endsWith("/argument")) {
MethodHandle callee = null;
if (mode.equals("unbox/argument")) {
// fail on handing surprise to int argument
callee = Surprise.INT_IDENTITY;
} else if (mode.equals("cast/argument")) {
// fail on handing surprise to Integer argument
callee = Surprise.BOX_IDENTITY;
}
if (callee != null) {
callee = callee.asType(MethodType.genericMethodType(1));
surprise = MethodHandles.filterArguments(callee, 0, surprise);
identity = MethodHandles.filterArguments(callee, 0, identity);
}
}
assertNotSame(mode, surprise, surprise0);
identity = identity.asType(MethodType.genericMethodType(1));
surprise = surprise.asType(MethodType.genericMethodType(1));
Object x = 42;
for (int i = 0; i < okCount; i++) {
Object y = identity.invokeExact(x);
assertEquals(x, y);
Object z = surprise.invokeExact(x);
assertEquals(x, z);
}
boo.boo("Boo!");
Object y = identity.invokeExact(x);
assertEquals(x, y);
try {
Object z = surprise.invokeExact(x);
System.out.println("Failed to throw; got z="+z);
assertTrue(false);
} catch (ClassCastException ex) {
if (verbosity > 2)
System.out.println("caught "+ex);
if (verbosity > 3)
ex.printStackTrace();
assertTrue(true); // all is well
}
}
static Example userMethod(Object o, String s, int i) {
called("userMethod", o, s, i);
return null;
}
@Test
public void testUserClassInSignature() throws Throwable {
if (CAN_SKIP_WORKING) return;
startTest("testUserClassInSignature");
Lookup lookup = MethodHandles.lookup();
String name; MethodType mt; MethodHandle mh;
Object[] args;
// Try a static method.
name = "userMethod";
mt = MethodType.methodType(Example.class, Object.class, String.class, int.class);
mh = lookup.findStatic(lookup.lookupClass(), name, mt);
assertEquals(mt, mh.type());
assertEquals(Example.class, mh.type().returnType());
args = randomArgs(mh.type().parameterArray());
mh.invokeWithArguments(args);
assertCalled(name, args);
// Try a virtual method.
name = "v2";
mt = MethodType.methodType(Object.class, Object.class, int.class);
mh = lookup.findVirtual(Example.class, name, mt);
assertEquals(mt, mh.type().dropParameterTypes(0,1));
assertTrue(mh.type().parameterList().contains(Example.class));
args = randomArgs(mh.type().parameterArray());
mh.invokeWithArguments(args);
assertCalled(name, args);
}
static void runForRunnable() {
called("runForRunnable");
}
public interface Fooable {
Object foo(Fooable x, Object y);
// this is for randomArg:
public class Impl implements Fooable {
public Object foo(Fooable x, Object y) {
throw new RuntimeException("do not call");
}
final String name;
public Impl() { name = "Fooable#"+nextArg(); }
@Override public String toString() { return name; }
}
}
static Object fooForFooable(Fooable x, Object y) {
return called("fooForFooable", x, y);
}
public static class MyCheckedException extends Exception {
}
public interface WillThrow {
void willThrow() throws MyCheckedException;
}
@Test
public void testAsInstance() throws Throwable {
if (CAN_SKIP_WORKING) return;
Lookup lookup = MethodHandles.lookup();
{
MethodType mt = MethodType.methodType(void.class);
MethodHandle mh = lookup.findStatic(MethodHandlesTest.class, "runForRunnable", mt);
Runnable proxy = MethodHandleProxies.asInterfaceInstance(Runnable.class, mh);
proxy.run();
assertCalled("runForRunnable");
}
{
MethodType mt = MethodType.methodType(Object.class, Fooable.class, Object.class);
MethodHandle mh = lookup.findStatic(MethodHandlesTest.class, "fooForFooable", mt);
Fooable proxy = MethodHandleProxies.asInterfaceInstance(Fooable.class, mh);
Object[] args = randomArgs(mt.parameterArray());
Object result = proxy.foo((Fooable) args[0], args[1]);
assertCalled("fooForFooable", args);
assertEquals(result, logEntry("fooForFooable", args));
}
for (Throwable ex : new Throwable[] { new NullPointerException("ok"),
new InternalError("ok"),
new Throwable("fail"),
new Exception("fail"),
new MyCheckedException()
}) {
MethodHandle mh = MethodHandles.throwException(void.class, Throwable.class);
mh = MethodHandles.insertArguments(mh, 0, ex);
WillThrow proxy = MethodHandleProxies.asInterfaceInstance(WillThrow.class, mh);
try {
proxy.willThrow();
System.out.println("Failed to throw: "+ex);
assertTrue(false);
} catch (Throwable ex1) {
if (verbosity > 2) {
System.out.println("throw "+ex);
System.out.println("catch "+(ex == ex1 ? "UNWRAPPED" : ex1));
}
if (ex instanceof RuntimeException ||
ex instanceof Error) {
assertSame("must pass unchecked exception out without wrapping", ex, ex1);
} else if (ex instanceof MyCheckedException) {
assertSame("must pass declared exception out without wrapping", ex, ex1);
} else {
assertNotSame("must pass undeclared checked exception with wrapping", ex, ex1);
if (!(ex1 instanceof UndeclaredThrowableException) || ex1.getCause() != ex) {
ex1.printStackTrace();
}
assertSame(ex, ex1.getCause());
UndeclaredThrowableException utex = (UndeclaredThrowableException) ex1;
}
}
}
// Test error checking:
for (Class<?> nonSAM : new Class[] { Object.class,
String.class,
CharSequence.class,
Example.class }) {
try {
MethodHandleProxies.asInterfaceInstance(nonSAM, varargsArray(0));
System.out.println("Failed to throw");
assertTrue(false);
} catch (IllegalArgumentException ex) {
}
}
}
}
// Local abbreviated copy of sun.invoke.util.ValueConversions
class ValueConversions {
private static final Lookup IMPL_LOOKUP = MethodHandles.lookup();
private static final Object[] NO_ARGS_ARRAY = {};
private static Object[] makeArray(Object... args) { return args; }
private static Object[] array() { return NO_ARGS_ARRAY; }
private static Object[] array(Object a0)
{ return makeArray(a0); }
private static Object[] array(Object a0, Object a1)
{ return makeArray(a0, a1); }
private static Object[] array(Object a0, Object a1, Object a2)
{ return makeArray(a0, a1, a2); }
private static Object[] array(Object a0, Object a1, Object a2, Object a3)
{ return makeArray(a0, a1, a2, a3); }
private static Object[] array(Object a0, Object a1, Object a2, Object a3,
Object a4)
{ return makeArray(a0, a1, a2, a3, a4); }
private static Object[] array(Object a0, Object a1, Object a2, Object a3,
Object a4, Object a5)
{ return makeArray(a0, a1, a2, a3, a4, a5); }
private static Object[] array(Object a0, Object a1, Object a2, Object a3,
Object a4, Object a5, Object a6)
{ return makeArray(a0, a1, a2, a3, a4, a5, a6); }
private static Object[] array(Object a0, Object a1, Object a2, Object a3,
Object a4, Object a5, Object a6, Object a7)
{ return makeArray(a0, a1, a2, a3, a4, a5, a6, a7); }
private static Object[] array(Object a0, Object a1, Object a2, Object a3,
Object a4, Object a5, Object a6, Object a7,
Object a8)
{ return makeArray(a0, a1, a2, a3, a4, a5, a6, a7, a8); }
private static Object[] array(Object a0, Object a1, Object a2, Object a3,
Object a4, Object a5, Object a6, Object a7,
Object a8, Object a9)
{ return makeArray(a0, a1, a2, a3, a4, a5, a6, a7, a8, a9); }
static MethodHandle[] makeArrays() {
ArrayList<MethodHandle> arrays = new ArrayList<MethodHandle>();
MethodHandles.Lookup lookup = IMPL_LOOKUP;
for (;;) {
int nargs = arrays.size();
MethodType type = MethodType.genericMethodType(nargs).changeReturnType(Object[].class);
String name = "array";
MethodHandle array = null;
try {
array = lookup.findStatic(ValueConversions.class, name, type);
} catch (ReflectiveOperationException ex) {
// break from loop!
}
if (array == null) break;
arrays.add(array);
}
assertTrue(arrays.size() == 11); // current number of methods
return arrays.toArray(new MethodHandle[0]);
}
static final MethodHandle[] ARRAYS = makeArrays();
/** Return a method handle that takes the indicated number of Object
* arguments and returns an Object array of them, as if for varargs.
*/
public static MethodHandle varargsArray(int nargs) {
if (nargs < ARRAYS.length)
return ARRAYS[nargs];
return MethodHandles.identity(Object[].class).asCollector(Object[].class, nargs);
}
public static MethodHandle varargsArray(Class<?> arrayType, int nargs) {
Class<?> elemType = arrayType.getComponentType();
MethodType vaType = MethodType.methodType(arrayType, Collections.<Class<?>>nCopies(nargs, elemType));
MethodHandle mh = varargsArray(nargs);
if (arrayType != Object[].class)
mh = MethodHandles.filterReturnValue(mh, CHANGE_ARRAY_TYPE.bindTo(arrayType));
return mh.asType(vaType);
}
static Object changeArrayType(Class<?> arrayType, Object[] a) {
Class<?> elemType = arrayType.getComponentType();
if (!elemType.isPrimitive())
return Arrays.copyOf(a, a.length, arrayType.asSubclass(Object[].class));
Object b = java.lang.reflect.Array.newInstance(elemType, a.length);
for (int i = 0; i < a.length; i++)
java.lang.reflect.Array.set(b, i, a[i]);
return b;
}
private static final MethodHandle CHANGE_ARRAY_TYPE;
static {
try {
CHANGE_ARRAY_TYPE = IMPL_LOOKUP.findStatic(ValueConversions.class, "changeArrayType",
MethodType.methodType(Object.class, Class.class, Object[].class));
} catch (NoSuchMethodException | IllegalAccessException ex) {
Error err = new InternalError("uncaught exception");
err.initCause(ex);
throw err;
}
}
private static final List<Object> NO_ARGS_LIST = Arrays.asList(NO_ARGS_ARRAY);
private static List<Object> makeList(Object... args) { return Arrays.asList(args); }
private static List<Object> list() { return NO_ARGS_LIST; }
private static List<Object> list(Object a0)
{ return makeList(a0); }
private static List<Object> list(Object a0, Object a1)
{ return makeList(a0, a1); }
private static List<Object> list(Object a0, Object a1, Object a2)
{ return makeList(a0, a1, a2); }
private static List<Object> list(Object a0, Object a1, Object a2, Object a3)
{ return makeList(a0, a1, a2, a3); }
private static List<Object> list(Object a0, Object a1, Object a2, Object a3,
Object a4)
{ return makeList(a0, a1, a2, a3, a4); }
private static List<Object> list(Object a0, Object a1, Object a2, Object a3,
Object a4, Object a5)
{ return makeList(a0, a1, a2, a3, a4, a5); }
private static List<Object> list(Object a0, Object a1, Object a2, Object a3,
Object a4, Object a5, Object a6)
{ return makeList(a0, a1, a2, a3, a4, a5, a6); }
private static List<Object> list(Object a0, Object a1, Object a2, Object a3,
Object a4, Object a5, Object a6, Object a7)
{ return makeList(a0, a1, a2, a3, a4, a5, a6, a7); }
private static List<Object> list(Object a0, Object a1, Object a2, Object a3,
Object a4, Object a5, Object a6, Object a7,
Object a8)
{ return makeList(a0, a1, a2, a3, a4, a5, a6, a7, a8); }
private static List<Object> list(Object a0, Object a1, Object a2, Object a3,
Object a4, Object a5, Object a6, Object a7,
Object a8, Object a9)
{ return makeList(a0, a1, a2, a3, a4, a5, a6, a7, a8, a9); }
static MethodHandle[] makeLists() {
ArrayList<MethodHandle> lists = new ArrayList<MethodHandle>();
MethodHandles.Lookup lookup = IMPL_LOOKUP;
for (;;) {
int nargs = lists.size();
MethodType type = MethodType.genericMethodType(nargs).changeReturnType(List.class);
String name = "list";
MethodHandle list = null;
try {
list = lookup.findStatic(ValueConversions.class, name, type);
} catch (ReflectiveOperationException ex) {
// break from loop!
}
if (list == null) break;
lists.add(list);
}
assertTrue(lists.size() == 11); // current number of methods
return lists.toArray(new MethodHandle[0]);
}
static final MethodHandle[] LISTS = makeLists();
static final MethodHandle AS_LIST;
static {
try {
AS_LIST = IMPL_LOOKUP.findStatic(Arrays.class, "asList", MethodType.methodType(List.class, Object[].class));
} catch (Exception ex) { throw new RuntimeException(ex); }
}
/** Return a method handle that takes the indicated number of Object
* arguments and returns List.
*/
public static MethodHandle varargsList(int nargs) {
if (nargs < LISTS.length)
return LISTS[nargs];
return AS_LIST.asCollector(Object[].class, nargs);
}
}
// This guy tests access from outside the same package member, but inside
// the package itself.
class PackageSibling {
static Lookup lookup() {
return MethodHandles.lookup();
}
}