/*
* Copyright 1998-2006 Sun Microsystems, Inc. All Rights Reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Sun designates this
* particular file as subject to the "Classpath" exception as provided
* by Sun in the LICENSE file that accompanied this code.
*
* 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).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
* CA 95054 USA or visit www.sun.com if you need additional information or
* have any questions.
*/
package com.sun.tools.jdi;
import com.sun.jdi.*;
import java.util.*;
import java.util.ArrayList;
public class ObjectReferenceImpl extends ValueImpl
implements ObjectReference, VMListener {
protected long ref;
private ReferenceType type = null;
private int gcDisableCount = 0;
boolean addedListener = false;
// This is cached only while the VM is suspended
protected static class Cache {
JDWP.ObjectReference.MonitorInfo monitorInfo = null;
}
private static final Cache noInitCache = new Cache();
private static final Cache markerCache = new Cache();
private Cache cache = noInitCache;
private void disableCache() {
synchronized (vm.state()) {
cache = null;
}
}
private void enableCache() {
synchronized (vm.state()) {
cache = markerCache;
}
}
// Override in subclasses
protected Cache newCache() {
return new Cache();
}
protected Cache getCache() {
synchronized (vm.state()) {
if (cache == noInitCache) {
if (vm.state().isSuspended()) {
// Set cache now, otherwise newly created objects are
// not cached until resuspend
enableCache();
} else {
disableCache();
}
}
if (cache == markerCache) {
cache = newCache();
}
return cache;
}
}
// Return the ClassTypeImpl upon which to invoke a method.
// By default it is our very own referenceType() but subclasses
// can override.
protected ClassTypeImpl invokableReferenceType(Method method) {
return (ClassTypeImpl)referenceType();
}
ObjectReferenceImpl(VirtualMachine aVm,long aRef) {
super(aVm);
ref = aRef;
}
protected String description() {
return "ObjectReference " + uniqueID();
}
/*
* VMListener implementation
*/
public boolean vmSuspended(VMAction action) {
enableCache();
return true;
}
public boolean vmNotSuspended(VMAction action) {
// make sure that cache and listener management are synchronized
synchronized (vm.state()) {
if (cache != null && (vm.traceFlags & vm.TRACE_OBJREFS) != 0) {
vm.printTrace("Clearing temporary cache for " + description());
}
disableCache();
if (addedListener) {
/*
* If a listener was added (i.e. this is not a
* ObjectReference that adds a listener on startup),
* remove it here.
*/
addedListener = false;
return false; // false says remove
} else {
return true;
}
}
}
public boolean equals(Object obj) {
if ((obj != null) && (obj instanceof ObjectReferenceImpl)) {
ObjectReferenceImpl other = (ObjectReferenceImpl)obj;
return (ref() == other.ref()) &&
super.equals(obj);
} else {
return false;
}
}
public int hashCode() {
return(int)ref();
}
public Type type() {
return referenceType();
}
public ReferenceType referenceType() {
if (type == null) {
try {
JDWP.ObjectReference.ReferenceType rtinfo =
JDWP.ObjectReference.ReferenceType.process(vm, this);
type = vm.referenceType(rtinfo.typeID,
rtinfo.refTypeTag);
} catch (JDWPException exc) {
throw exc.toJDIException();
}
}
return type;
}
public Value getValue(Field sig) {
List<Field> list = new ArrayList<Field>(1);
list.add(sig);
Map map = getValues(list);
return(Value)map.get(sig);
}
public Map<Field,Value> getValues(List<? extends Field> theFields) {
validateMirrors(theFields);
List<Field> staticFields = new ArrayList<Field>(0);
int size = theFields.size();
List<Field> instanceFields = new ArrayList<Field>(size);
for (int i=0; i<size; i++) {
Field field = (Field)theFields.get(i);
// Make sure the field is valid
((ReferenceTypeImpl)referenceType()).validateFieldAccess(field);
// FIX ME! We need to do some sanity checking
// here; make sure the field belongs to this
// object.
if (field.isStatic())
staticFields.add(field);
else {
instanceFields.add(field);
}
}
Map<Field, Value> map;
if (staticFields.size() > 0) {
map = referenceType().getValues(staticFields);
} else {
map = new HashMap<Field, Value>(size);
}
size = instanceFields.size();
JDWP.ObjectReference.GetValues.Field[] queryFields =
new JDWP.ObjectReference.GetValues.Field[size];
for (int i=0; i<size; i++) {
FieldImpl field = (FieldImpl)instanceFields.get(i);/* thanks OTI */
queryFields[i] = new JDWP.ObjectReference.GetValues.Field(
field.ref());
}
ValueImpl[] values;
try {
values = JDWP.ObjectReference.GetValues.
process(vm, this, queryFields).values;
} catch (JDWPException exc) {
throw exc.toJDIException();
}
if (size != values.length) {
throw new InternalException(
"Wrong number of values returned from target VM");
}
for (int i=0; i<size; i++) {
FieldImpl field = (FieldImpl)instanceFields.get(i);
map.put(field, values[i]);
}
return map;
}
public void setValue(Field field, Value value)
throws InvalidTypeException, ClassNotLoadedException {
validateMirror(field);
validateMirrorOrNull(value);
// Make sure the field is valid
((ReferenceTypeImpl)referenceType()).validateFieldSet(field);
if (field.isStatic()) {
ReferenceType type = referenceType();
if (type instanceof ClassType) {
((ClassType)type).setValue(field, value);
return;
} else {
throw new IllegalArgumentException(
"Invalid type for static field set");
}
}
try {
JDWP.ObjectReference.SetValues.FieldValue[] fvals =
new JDWP.ObjectReference.SetValues.FieldValue[1];
fvals[0] = new JDWP.ObjectReference.SetValues.FieldValue(
((FieldImpl)field).ref(),
// Validate and convert if necessary
ValueImpl.prepareForAssignment(value,
(FieldImpl)field));
try {
JDWP.ObjectReference.SetValues.process(vm, this, fvals);
} catch (JDWPException exc) {
throw exc.toJDIException();
}
} catch (ClassNotLoadedException e) {
/*
* Since we got this exception,
* the field type must be a reference type. The value
* we're trying to set is null, but if the field's
* class has not yet been loaded through the enclosing
* class loader, then setting to null is essentially a
* no-op, and we should allow it without an exception.
*/
if (value != null) {
throw e;
}
}
}
void validateMethodInvocation(Method method, int options)
throws InvalidTypeException,
InvocationException {
/*
* Method must be in this object's class, a superclass, or
* implemented interface
*/
ReferenceTypeImpl declType = (ReferenceTypeImpl)method.declaringType();
if (!declType.isAssignableFrom(this)) {
throw new IllegalArgumentException("Invalid method");
}
ClassTypeImpl clazz = invokableReferenceType(method);
/*
* Method must be a non-constructor
*/
if (method.isConstructor()) {
throw new IllegalArgumentException("Cannot invoke constructor");
}
/*
* For nonvirtual invokes, method must have a body
*/
if ((options & INVOKE_NONVIRTUAL) != 0) {
if (method.declaringType() instanceof InterfaceType) {
throw new IllegalArgumentException("Interface method");
} else if (method.isAbstract()) {
throw new IllegalArgumentException("Abstract method");
}
}
/*
* Get the class containing the method that will be invoked.
* This class is needed only for proper validation of the
* method argument types.
*/
ClassTypeImpl invokedClass;
if ((options & INVOKE_NONVIRTUAL) != 0) {
// No overrides in non-virtual invokes
invokedClass = clazz;
} else {
/*
* For virtual invokes, find any override of the method.
* Since we are looking for a method with a real body, we
* don't need to bother with interfaces/abstract methods.
*/
Method invoker = clazz.concreteMethodByName(method.name(),
method.signature());
// isAssignableFrom check above guarantees non-null
invokedClass = (ClassTypeImpl)invoker.declaringType();
}
/* The above code is left over from previous versions.
* We haven't had time to divine the intent. jjh, 7/31/2003
*/
}
PacketStream sendInvokeCommand(final ThreadReferenceImpl thread,
final ClassTypeImpl refType,
final MethodImpl method,
final ValueImpl[] args,
final int options) {
CommandSender sender =
new CommandSender() {
public PacketStream send() {
return JDWP.ObjectReference.InvokeMethod.enqueueCommand(
vm, ObjectReferenceImpl.this,
thread, refType,
method.ref(), args, options);
}
};
PacketStream stream;
if ((options & INVOKE_SINGLE_THREADED) != 0) {
stream = thread.sendResumingCommand(sender);
} else {
stream = vm.sendResumingCommand(sender);
}
return stream;
}
public Value invokeMethod(ThreadReference threadIntf, Method methodIntf,
List<? extends Value> origArguments, int options)
throws InvalidTypeException,
IncompatibleThreadStateException,
InvocationException,
ClassNotLoadedException {
validateMirror(threadIntf);
validateMirror(methodIntf);
validateMirrorsOrNulls(origArguments);
MethodImpl method = (MethodImpl)methodIntf;
ThreadReferenceImpl thread = (ThreadReferenceImpl)threadIntf;
if (method.isStatic()) {
if (referenceType() instanceof ClassType) {
ClassType type = (ClassType)referenceType();
return type.invokeMethod(thread, method, origArguments, options);
} else {
throw new IllegalArgumentException("Invalid type for static method invocation");
}
}
validateMethodInvocation(method, options);
List<Value> arguments = method.validateAndPrepareArgumentsForInvoke(
origArguments);
ValueImpl[] args = (ValueImpl[])arguments.toArray(new ValueImpl[0]);
JDWP.ObjectReference.InvokeMethod ret;
try {
PacketStream stream =
sendInvokeCommand(thread, invokableReferenceType(method),
method, args, options);
ret = JDWP.ObjectReference.InvokeMethod.waitForReply(vm, stream);
} catch (JDWPException exc) {
if (exc.errorCode() == JDWP.Error.INVALID_THREAD) {
throw new IncompatibleThreadStateException();
} else {
throw exc.toJDIException();
}
}
/*
* There is an implict VM-wide suspend at the conclusion
* of a normal (non-single-threaded) method invoke
*/
if ((options & INVOKE_SINGLE_THREADED) == 0) {
vm.notifySuspend();
}
if (ret.exception != null) {
throw new InvocationException(ret.exception);
} else {
return ret.returnValue;
}
}
/* leave synchronized to keep count accurate */
public synchronized void disableCollection() {
if (gcDisableCount == 0) {
try {
JDWP.ObjectReference.DisableCollection.process(vm, this);
} catch (JDWPException exc) {
throw exc.toJDIException();
}
}
gcDisableCount++;
}
/* leave synchronized to keep count accurate */
public synchronized void enableCollection() {
gcDisableCount--;
if (gcDisableCount == 0) {
try {
JDWP.ObjectReference.EnableCollection.process(vm, this);
} catch (JDWPException exc) {
// If already collected, no harm done, no exception
if (exc.errorCode() != JDWP.Error.INVALID_OBJECT) {
throw exc.toJDIException();
}
return;
}
}
}
public boolean isCollected() {
try {
return JDWP.ObjectReference.IsCollected.process(vm, this).
isCollected;
} catch (JDWPException exc) {
throw exc.toJDIException();
}
}
public long uniqueID() {
return ref();
}
JDWP.ObjectReference.MonitorInfo jdwpMonitorInfo()
throws IncompatibleThreadStateException {
JDWP.ObjectReference.MonitorInfo info = null;
try {
Cache local;
// getCache() and addlistener() must be synchronized
// so that no events are lost.
synchronized (vm.state()) {
local = getCache();
if (local != null) {
info = local.monitorInfo;
// Check if there will be something to cache
// and there is not already a listener
if (info == null && !vm.state().hasListener(this)) {
/* For other, less numerous objects, this is done
* in the constructor. Since there can be many
* ObjectReferences, the VM listener is installed
* and removed as needed.
* Listener must be installed before process()
*/
vm.state().addListener(this);
addedListener = true;
}
}
}
if (info == null) {
info = JDWP.ObjectReference.MonitorInfo.process(vm, this);
if (local != null) {
local.monitorInfo = info;
if ((vm.traceFlags & vm.TRACE_OBJREFS) != 0) {
vm.printTrace("ObjectReference " + uniqueID() +
" temporarily caching monitor info");
}
}
}
} catch (JDWPException exc) {
if (exc.errorCode() == JDWP.Error.THREAD_NOT_SUSPENDED) {
throw new IncompatibleThreadStateException();
} else {
throw exc.toJDIException();
}
}
return info;
}
public List<ThreadReference> waitingThreads() throws IncompatibleThreadStateException {
return Arrays.asList((ThreadReference[])jdwpMonitorInfo().waiters);
}
public ThreadReference owningThread() throws IncompatibleThreadStateException {
return jdwpMonitorInfo().owner;
}
public int entryCount() throws IncompatibleThreadStateException {
return jdwpMonitorInfo().entryCount;
}
public List<ObjectReference> referringObjects(long maxReferrers) {
if (!vm.canGetInstanceInfo()) {
throw new UnsupportedOperationException(
"target does not support getting referring objects");
}
if (maxReferrers < 0) {
throw new IllegalArgumentException("maxReferrers is less than zero: "
+ maxReferrers);
}
int intMax = (maxReferrers > Integer.MAX_VALUE)?
Integer.MAX_VALUE: (int)maxReferrers;
// JDWP can't currently handle more than this (in mustang)
try {
return Arrays.asList((ObjectReference[])JDWP.ObjectReference.ReferringObjects.
process(vm, this, intMax).referringObjects);
} catch (JDWPException exc) {
throw exc.toJDIException();
}
}
long ref() {
return ref;
}
boolean isClassObject() {
/*
* Don't need to worry about subclasses since java.lang.Class is final.
*/
return referenceType().name().equals("java.lang.Class");
}
ValueImpl prepareForAssignmentTo(ValueContainer destination)
throws InvalidTypeException,
ClassNotLoadedException {
validateAssignment(destination);
return this; // conversion never necessary
}
void validateAssignment(ValueContainer destination)
throws InvalidTypeException, ClassNotLoadedException {
/*
* Do these simpler checks before attempting a query of the destination's
* type which might cause a confusing ClassNotLoadedException if
* the destination is primitive or an array.
*/
/*
* TO DO: Centralize JNI signature knowledge
*/
if (destination.signature().length() == 1) {
throw new InvalidTypeException("Can't assign object value to primitive");
}
if ((destination.signature().charAt(0) == '[') &&
(type().signature().charAt(0) != '[')) {
throw new InvalidTypeException("Can't assign non-array value to an array");
}
if ("void".equals(destination.typeName())) {
throw new InvalidTypeException("Can't assign object value to a void");
}
// Validate assignment
ReferenceType destType = (ReferenceTypeImpl)destination.type();
ReferenceTypeImpl myType = (ReferenceTypeImpl)referenceType();
if (!myType.isAssignableTo((ReferenceType)destType)) {
JNITypeParser parser = new JNITypeParser(destType.signature());
String destTypeName = parser.typeName();
throw new InvalidTypeException("Can't assign " +
type().name() +
" to " + destTypeName);
}
}
public String toString() {
return "instance of " + referenceType().name() + "(id=" + uniqueID() + ")";
}
byte typeValueKey() {
return JDWP.Tag.OBJECT;
}
}