/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing,
* software distributed under the License is distributed on an
* "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
* KIND, either express or implied. See the License for the
* specific language governing permissions and limitations
* under the License.
*/
package org.codehaus.groovy.classgen.asm;
import org.codehaus.groovy.ast.*;
import org.codehaus.groovy.ast.decompiled.DecompiledClassNode;
import org.codehaus.groovy.reflection.ReflectionCache;
import org.codehaus.groovy.runtime.typehandling.DefaultTypeTransformation;
import org.objectweb.asm.Label;
import org.objectweb.asm.MethodVisitor;
import org.objectweb.asm.Opcodes;
import java.lang.reflect.Modifier;
/**
* A helper class for bytecode generation with AsmClassGenerator.
*
* @author <a href="mailto:james@coredevelopers.net">James Strachan</a>
* @author <a href="mailto:b55r@sina.com">Bing Ran</a>
* @author <a href="mailto:blackdrag@gmx.org">Jochen Theodorou</a>
*/
public class BytecodeHelper implements Opcodes {
private static String DTT_CLASSNAME = BytecodeHelper.getClassInternalName(DefaultTypeTransformation.class.getName());
public static String getClassInternalName(ClassNode t) {
if (t.isPrimaryClassNode() || t instanceof DecompiledClassNode) {
if (t.isArray()) return "[L"+getClassInternalName(t.getComponentType())+";";
return getClassInternalName(t.getName());
}
return getClassInternalName(t.getTypeClass());
}
public static String getClassInternalName(Class t) {
return org.objectweb.asm.Type.getInternalName(t);
}
/**
* @return the ASM internal name of the type
*/
public static String getClassInternalName(String name) {
return name.replace('.', '/');
}
public static String getMethodDescriptor(ClassNode returnType, Parameter[] parameters) {
StringBuilder buffer = new StringBuilder("(");
for (int i = 0; i < parameters.length; i++) {
buffer.append(getTypeDescription(parameters[i].getType()));
}
buffer.append(")");
buffer.append(getTypeDescription(returnType));
return buffer.toString();
}
/**
* Returns a method descriptor for the given {@link org.codehaus.groovy.ast.MethodNode}.
*
* @param methodNode the method node for which to create the descriptor
* @return a method descriptor as defined in section JVMS section 4.3.3
*/
public static String getMethodDescriptor(MethodNode methodNode) {
return getMethodDescriptor(methodNode.getReturnType(), methodNode.getParameters());
}
/**
* @return the ASM method type descriptor
*/
public static String getMethodDescriptor(Class returnType, Class[] paramTypes) {
// lets avoid class loading
StringBuilder buffer = new StringBuilder("(");
for (int i = 0; i < paramTypes.length; i++) {
buffer.append(getTypeDescription(paramTypes[i]));
}
buffer.append(")");
buffer.append(getTypeDescription(returnType));
return buffer.toString();
}
public static String getTypeDescription(Class c) {
return org.objectweb.asm.Type.getDescriptor(c);
}
/**
* array types are special:
* eg.: String[]: classname: [Ljava.lang.String;
* Object: classname: java.lang.Object
* int[] : classname: [I
* unlike getTypeDescription '.' is not replaced by '/'.
* it seems that makes problems for
* the class loading if '.' is replaced by '/'
*
* @return the ASM type description for class loading
*/
public static String getClassLoadingTypeDescription(ClassNode c) {
StringBuilder buf = new StringBuilder();
boolean array = false;
while (true) {
if (c.isArray()) {
buf.append('[');
c = c.getComponentType();
array = true;
} else {
if (ClassHelper.isPrimitiveType(c)) {
buf.append(getTypeDescription(c));
} else {
if (array) buf.append('L');
buf.append(c.getName());
if (array) buf.append(';');
}
return buf.toString();
}
}
}
/**
* array types are special:
* eg.: String[]: classname: [Ljava/lang/String;
* int[]: [I
*
* @return the ASM type description
*/
public static String getTypeDescription(ClassNode c) {
return getTypeDescription(c, true);
}
/**
* array types are special:
* eg.: String[]: classname: [Ljava/lang/String;
* int[]: [I
*
* @return the ASM type description
*/
private static String getTypeDescription(ClassNode c, boolean end) {
StringBuilder buf = new StringBuilder();
ClassNode d = c;
while (true) {
if (ClassHelper.isPrimitiveType(d.redirect())) {
d = d.redirect();
char car;
if (d == ClassHelper.int_TYPE) {
car = 'I';
} else if (d == ClassHelper.VOID_TYPE) {
car = 'V';
} else if (d == ClassHelper.boolean_TYPE) {
car = 'Z';
} else if (d == ClassHelper.byte_TYPE) {
car = 'B';
} else if (d == ClassHelper.char_TYPE) {
car = 'C';
} else if (d == ClassHelper.short_TYPE) {
car = 'S';
} else if (d == ClassHelper.double_TYPE) {
car = 'D';
} else if (d == ClassHelper.float_TYPE) {
car = 'F';
} else /* long */ {
car = 'J';
}
buf.append(car);
return buf.toString();
} else if (d.isArray()) {
buf.append('[');
d = d.getComponentType();
} else {
buf.append('L');
String name = d.getName();
int len = name.length();
for (int i = 0; i < len; ++i) {
char car = name.charAt(i);
buf.append(car == '.' ? '/' : car);
}
if (end) buf.append(';');
return buf.toString();
}
}
}
/**
* @return an array of ASM internal names of the type
*/
public static String[] getClassInternalNames(ClassNode[] names) {
int size = names.length;
String[] answer = new String[size];
for (int i = 0; i < size; i++) {
answer[i] = getClassInternalName(names[i]);
}
return answer;
}
public static void pushConstant(MethodVisitor mv, int value) {
switch (value) {
case 0:
mv.visitInsn(ICONST_0);
break;
case 1:
mv.visitInsn(ICONST_1);
break;
case 2:
mv.visitInsn(ICONST_2);
break;
case 3:
mv.visitInsn(ICONST_3);
break;
case 4:
mv.visitInsn(ICONST_4);
break;
case 5:
mv.visitInsn(ICONST_5);
break;
default:
if (value >= Byte.MIN_VALUE && value <= Byte.MAX_VALUE) {
mv.visitIntInsn(BIPUSH, value);
} else if (value >= Short.MIN_VALUE && value <= Short.MAX_VALUE) {
mv.visitIntInsn(SIPUSH, value);
} else {
mv.visitLdcInsn(Integer.valueOf(value));
}
}
}
/**
* negate a boolean on stack. true->false, false->true
*/
public static void negateBoolean(MethodVisitor mv) {
// code to negate the primitive boolean
Label endLabel = new Label();
Label falseLabel = new Label();
mv.visitJumpInsn(IFNE, falseLabel);
mv.visitInsn(ICONST_1);
mv.visitJumpInsn(GOTO, endLabel);
mv.visitLabel(falseLabel);
mv.visitInsn(ICONST_0);
mv.visitLabel(endLabel);
}
/**
* load a message on the stack and remove it right away. Good for put a mark in the generated bytecode for debugging purpose.
*
* @param msg
*/
/*public void mark(String msg) {
mv.visitLdcInsn(msg);
mv.visitInsn(POP);
}*/
/**
* returns a name that Class.forName() can take. Notably for arrays:
* [I, [Ljava.lang.String; etc
* Regular object type: java.lang.String
*
* @param name
*/
public static String formatNameForClassLoading(String name) {
if (name == null) {
return "java.lang.Object;";
}
if (name.equals("int")
|| name.equals("long")
|| name.equals("short")
|| name.equals("float")
|| name.equals("double")
|| name.equals("byte")
|| name.equals("char")
|| name.equals("boolean")
|| name.equals("void")
) {
return name;
}
if (name.startsWith("[")) {
return name.replace('/', '.');
}
if (name.startsWith("L")) {
name = name.substring(1);
if (name.endsWith(";")) {
name = name.substring(0, name.length() - 1);
}
return name.replace('/', '.');
}
String prefix = "";
if (name.endsWith("[]")) { // todo need process multi
prefix = "[";
name = name.substring(0, name.length() - 2);
if (name.equals("int")) {
return prefix + "I";
} else if (name.equals("long")) {
return prefix + "J";
} else if (name.equals("short")) {
return prefix + "S";
} else if (name.equals("float")) {
return prefix + "F";
} else if (name.equals("double")) {
return prefix + "D";
} else if (name.equals("byte")) {
return prefix + "B";
} else if (name.equals("char")) {
return prefix + "C";
} else if (name.equals("boolean")) {
return prefix + "Z";
} else {
return prefix + "L" + name.replace('/', '.') + ";";
}
}
return name.replace('/', '.');
}
/*public void dup() {
mv.visitInsn(DUP);
}*/
public static void doReturn(MethodVisitor mv, ClassNode returnType) {
if (returnType == ClassHelper.double_TYPE) {
mv.visitInsn(DRETURN);
} else if (returnType == ClassHelper.float_TYPE) {
mv.visitInsn(FRETURN);
} else if (returnType == ClassHelper.long_TYPE) {
mv.visitInsn(LRETURN);
} else if (
returnType == ClassHelper.boolean_TYPE
|| returnType == ClassHelper.char_TYPE
|| returnType == ClassHelper.byte_TYPE
|| returnType == ClassHelper.int_TYPE
|| returnType == ClassHelper.short_TYPE) {
//byte,short,boolean,int are all IRETURN
mv.visitInsn(IRETURN);
} else if (returnType == ClassHelper.VOID_TYPE) {
mv.visitInsn(RETURN);
} else {
mv.visitInsn(ARETURN);
}
}
private static boolean hasGenerics(Parameter[] param) {
if (param.length == 0) return false;
for (int i = 0; i < param.length; i++) {
ClassNode type = param[i].getType();
if (hasGenerics(type)) return true;
}
return false;
}
private static boolean hasGenerics(ClassNode type) {
return type.isArray() ? hasGenerics(type.getComponentType()) : type.getGenericsTypes() != null;
}
public static String getGenericsMethodSignature(MethodNode node) {
GenericsType[] generics = node.getGenericsTypes();
Parameter[] param = node.getParameters();
ClassNode returnType = node.getReturnType();
if (generics == null && !hasGenerics(param) && !hasGenerics(returnType)) return null;
StringBuilder ret = new StringBuilder(100);
getGenericsTypeSpec(ret, generics);
GenericsType[] paramTypes = new GenericsType[param.length];
for (int i = 0; i < param.length; i++) {
ClassNode pType = param[i].getType();
if (pType.getGenericsTypes() == null || !pType.isGenericsPlaceHolder()) {
paramTypes[i] = new GenericsType(pType);
} else {
paramTypes[i] = pType.getGenericsTypes()[0];
}
}
addSubTypes(ret, paramTypes, "(", ")");
addSubTypes(ret, new GenericsType[]{new GenericsType(returnType)}, "", "");
return ret.toString();
}
private static boolean usesGenericsInClassSignature(ClassNode node) {
if (!node.isUsingGenerics()) return false;
if (hasGenerics(node)) return true;
ClassNode sclass = node.getUnresolvedSuperClass(false);
if (sclass.isUsingGenerics()) return true;
ClassNode[] interfaces = node.getInterfaces();
if (interfaces != null) {
for (int i = 0; i < interfaces.length; i++) {
if (interfaces[i].isUsingGenerics()) return true;
}
}
return false;
}
public static String getGenericsSignature(ClassNode node) {
if (!usesGenericsInClassSignature(node)) return null;
GenericsType[] genericsTypes = node.getGenericsTypes();
StringBuilder ret = new StringBuilder(100);
getGenericsTypeSpec(ret, genericsTypes);
GenericsType extendsPart = new GenericsType(node.getUnresolvedSuperClass(false));
writeGenericsBounds(ret, extendsPart, true);
ClassNode[] interfaces = node.getInterfaces();
for (int i = 0; i < interfaces.length; i++) {
GenericsType interfacePart = new GenericsType(interfaces[i]);
writeGenericsBounds(ret, interfacePart, false);
}
return ret.toString();
}
private static void getGenericsTypeSpec(StringBuilder ret, GenericsType[] genericsTypes) {
if (genericsTypes == null) return;
ret.append('<');
for (int i = 0; i < genericsTypes.length; i++) {
String name = genericsTypes[i].getName();
ret.append(name);
ret.append(':');
writeGenericsBounds(ret, genericsTypes[i], true);
}
ret.append('>');
}
public static String getGenericsBounds(ClassNode type) {
GenericsType[] genericsTypes = type.getGenericsTypes();
if (genericsTypes == null) return null;
StringBuilder ret = new StringBuilder(100);
if (type.isGenericsPlaceHolder()) {
addSubTypes(ret, type.getGenericsTypes(), "", "");
} else {
GenericsType gt = new GenericsType(type);
writeGenericsBounds(ret, gt, false);
}
return ret.toString();
}
private static void writeGenericsBoundType(StringBuilder ret, ClassNode printType, boolean writeInterfaceMarker) {
if (writeInterfaceMarker && printType.isInterface()) ret.append(":");
if (printType.isGenericsPlaceHolder() && printType.getGenericsTypes()!=null) {
ret.append("T");
ret.append(printType.getGenericsTypes()[0].getName());
ret.append(";");
}
else {
ret.append(getTypeDescription(printType, false));
addSubTypes(ret, printType.getGenericsTypes(), "<", ">");
if (!ClassHelper.isPrimitiveType(printType)) ret.append(";");
}
}
private static void writeGenericsBounds(StringBuilder ret, GenericsType type, boolean writeInterfaceMarker) {
if (type.getUpperBounds() != null) {
ClassNode[] bounds = type.getUpperBounds();
for (int i = 0; i < bounds.length; i++) {
writeGenericsBoundType(ret, bounds[i], writeInterfaceMarker);
}
} else if (type.getLowerBound() != null) {
writeGenericsBoundType(ret, type.getLowerBound(), writeInterfaceMarker);
} else {
writeGenericsBoundType(ret, type.getType(), writeInterfaceMarker);
}
}
private static void addSubTypes(StringBuilder ret, GenericsType[] types, String start, String end) {
if (types == null) return;
ret.append(start);
for (int i = 0; i < types.length; i++) {
if (types[i].getType().isArray()) {
ret.append("[");
addSubTypes(ret, new GenericsType[]{new GenericsType(types[i].getType().getComponentType())}, "", "");
}
else {
if (types[i].isPlaceholder()) {
ret.append('T');
String name = types[i].getName();
ret.append(name);
ret.append(';');
} else if (types[i].isWildcard()) {
if (types[i].getUpperBounds() != null) {
ret.append('+');
writeGenericsBounds(ret, types[i], false);
} else if (types[i].getLowerBound() != null) {
ret.append('-');
writeGenericsBounds(ret, types[i], false);
} else {
ret.append('*');
}
} else {
writeGenericsBounds(ret, types[i], false);
}
}
}
ret.append(end);
}
public static void load(MethodVisitor mv, ClassNode type, int idx) {
if (type == ClassHelper.double_TYPE) {
mv.visitVarInsn(DLOAD, idx);
} else if (type == ClassHelper.float_TYPE) {
mv.visitVarInsn(FLOAD, idx);
} else if (type == ClassHelper.long_TYPE) {
mv.visitVarInsn(LLOAD, idx);
} else if (
type == ClassHelper.boolean_TYPE
|| type == ClassHelper.char_TYPE
|| type == ClassHelper.byte_TYPE
|| type == ClassHelper.int_TYPE
|| type == ClassHelper.short_TYPE) {
mv.visitVarInsn(ILOAD, idx);
} else {
mv.visitVarInsn(ALOAD, idx);
}
}
public static void doCast(MethodVisitor mv, ClassNode type) {
if (type == ClassHelper.OBJECT_TYPE) return;
if (ClassHelper.isPrimitiveType(type) && type != ClassHelper.VOID_TYPE) {
unbox(mv, type);
} else {
mv.visitTypeInsn(
CHECKCAST,
type.isArray() ?
BytecodeHelper.getTypeDescription(type) :
BytecodeHelper.getClassInternalName(type.getName()));
}
}
/**
* Given a wrapped number type (Byte, Integer, Short, ...), generates bytecode
* to convert it to a primitive number (int, long, double) using calls to
* wrapped.[targetType]Value()
* @param mv method visitor
* @param sourceType the wrapped number type
* @param targetType the primitive target type
*/
public static void doCastToPrimitive(MethodVisitor mv, ClassNode sourceType, ClassNode targetType) {
mv.visitMethodInsn(INVOKEVIRTUAL, BytecodeHelper.getClassInternalName(sourceType), targetType.getName() + "Value", "()" + BytecodeHelper.getTypeDescription(targetType), false);
}
/**
* Given a primitive number type (byte, integer, short, ...), generates bytecode
* to convert it to a wrapped number (Integer, Long, Double) using calls to
* [WrappedType].valueOf
* @param mv method visitor
* @param sourceType the primitive number type
* @param targetType the wrapped target type
*/
public static void doCastToWrappedType(MethodVisitor mv, ClassNode sourceType, ClassNode targetType) {
mv.visitMethodInsn(INVOKESTATIC, getClassInternalName(targetType), "valueOf", "(" + getTypeDescription(sourceType) + ")" + getTypeDescription(targetType), false);
}
public static void doCast(MethodVisitor mv, Class type) {
if (type == Object.class) return;
if (type.isPrimitive() && type != Void.TYPE) {
unbox(mv, type);
} else {
mv.visitTypeInsn(
CHECKCAST,
type.isArray() ?
BytecodeHelper.getTypeDescription(type) :
BytecodeHelper.getClassInternalName(type.getName()));
}
}
/**
* Generates the bytecode to unbox the current value on the stack
*/
public static void unbox(MethodVisitor mv, Class type) {
if (type.isPrimitive() && type != Void.TYPE) {
String returnString = "(Ljava/lang/Object;)" + BytecodeHelper.getTypeDescription(type);
mv.visitMethodInsn(INVOKESTATIC, DTT_CLASSNAME, type.getName() + "Unbox", returnString, false);
}
}
public static void unbox(MethodVisitor mv, ClassNode type) {
if (type.isPrimaryClassNode()) return;
unbox(mv, type.getTypeClass());
}
/**
* box top level operand
*/
@Deprecated
public static boolean box(MethodVisitor mv, ClassNode type) {
if (type.isPrimaryClassNode()) return false;
return box(mv, type.getTypeClass());
}
/**
* Generates the bytecode to autobox the current value on the stack
*/
@Deprecated
public static boolean box(MethodVisitor mv, Class type) {
if (ReflectionCache.getCachedClass(type).isPrimitive && type != void.class) {
String returnString = "(" + BytecodeHelper.getTypeDescription(type) + ")Ljava/lang/Object;";
mv.visitMethodInsn(INVOKESTATIC, DTT_CLASSNAME, "box", returnString, false);
return true;
}
return false;
}
/**
* Visits a class literal. If the type of the classnode is a primitive type,
* the generated bytecode will be a GETSTATIC Integer.TYPE.
* If the classnode is not a primitive type, we will generate a LDC instruction.
*/
public static void visitClassLiteral(MethodVisitor mv, ClassNode classNode) {
if (ClassHelper.isPrimitiveType(classNode)) {
mv.visitFieldInsn(
GETSTATIC,
getClassInternalName(ClassHelper.getWrapper(classNode)),
"TYPE",
"Ljava/lang/Class;");
} else {
mv.visitLdcInsn(org.objectweb.asm.Type.getType(getTypeDescription(classNode)));
}
}
/**
* Tells if a class node is candidate for class literal bytecode optimization. If so,
* bytecode may use LDC instructions instead of static constant Class fields to retrieve
* class literals.
* @param classNode the classnode for which we want to know if bytecode optimization is possible
* @return true if the bytecode can be optimized
*/
public static boolean isClassLiteralPossible(ClassNode classNode) {
// the current implementation only checks for public modifier, because Groovy used to allow
// handles on classes even if they are package protected and not in the same package.
// There are situations where we could make more fine grained checks, but be careful of
// potential breakage of existing code.
return Modifier.isPublic(classNode.getModifiers());
}
/**
* Returns true if the two classes share the same compilation unit.
* @param a class a
* @param b class b
* @return true if both classes share the same compilation unit
*/
public static boolean isSameCompilationUnit(ClassNode a, ClassNode b) {
CompileUnit cu1 = a.getCompileUnit();
CompileUnit cu2 = b.getCompileUnit();
return cu1 !=null && cu2 !=null && cu1==cu2;
}
/**
* Computes a hash code for a string. The purpose of this hashcode is to be constant independently of
* the JDK being used.
* @param str the string for which to compute the hashcode
* @return hashcode of the string
*/
public static int hashCode(String str) {
final char[] chars = str.toCharArray();
int h = 0;
for (int i = 0; i < chars.length; i++) {
h = 31 * h + chars[i];
}
return h;
}
}