org.eclipse.jdt.debug/jdi/org/eclipse/jdi/internal/ObjectReferenceImpl.java - jdt/eclipse.jdt.debug - Git at Google

 package org.eclipse.jdi.internal;

 /*
  * (c) Copyright IBM Corp. 2000, 2001.
  * All Rights Reserved.
  */

 import com.sun.jdi.*;
 import com.sun.jdi.connect.*;
 import com.sun.jdi.event.*;
 import com.sun.jdi.request.*;
 import org.eclipse.jdi.internal.connect.*;
 import org.eclipse.jdi.internal.request.*;
 import org.eclipse.jdi.internal.event.*;
 import org.eclipse.jdi.internal.jdwp.*;
 import org.eclipse.jdi.internal.spy.*;
 import java.util.*;
 import java.io.*;

 /**
  * this class implements the corresponding interfaces
  * declared by the JDI specification. See the com.sun.jdi package
  * for more information.
  *
  */
 public class ObjectReferenceImpl extends ValueImpl implements ObjectReference {
 	/** JDWP Tag. */
 	public static final byte tag = JdwpID.OBJECT_TAG;

 	/** ObjectID of object that corresponds to this reference. */
 	private JdwpObjectID fObjectID;

 	/**
 	 * Creates new ObjectReferenceImpl.
 	 */
 	public ObjectReferenceImpl(VirtualMachineImpl vmImpl, JdwpObjectID objectID) {
 		this("ObjectReference", vmImpl, objectID);
 	}

 	/**
 	 * Creates new ObjectReferenceImpl.
 	 */
 	public ObjectReferenceImpl(String description, VirtualMachineImpl vmImpl, JdwpObjectID objectID) {
 		super(description, vmImpl);
 		fObjectID = objectID;
 	}

 	/**
 	 * @returns tag.
 	 */
 	public byte getTag() {
 		return tag;
 	}

 	/**
 	 * @return Returns Jdwp Object ID.
 	 */
 	public JdwpObjectID getObjectID() {
 		return fObjectID;
 	}

 	/**
 	 * Prevents garbage collection for this object.
 	 */
 	public void disableCollection() {
 		initJdwpRequest();
 		try {
 			JdwpReplyPacket replyPacket = requestVM(JdwpCommandPacket.OR_DISABLE_COLLECTION, this);
 			defaultReplyErrorHandler(replyPacket.errorCode());
 		} finally {
 			handledJdwpRequest();
 		}
 	}

 	/**
 	 * Permits garbage collection for this object.
 	 */
 	public void enableCollection() {
 		initJdwpRequest();
 		try {
 			JdwpReplyPacket replyPacket = requestVM(JdwpCommandPacket.OR_ENABLE_COLLECTION, this);
 			defaultReplyErrorHandler(replyPacket.errorCode());
 		} finally {
 			handledJdwpRequest();
 		}
 	}

 	/**
 	 * Inner class used to return monitor info.
 	 */
 	private class MonitorInfo {
 		ThreadReferenceImpl owner;
 		int entryCount;
 		ArrayList waiters;
 	}

 	/**
 	 * @return Returns monitor info.
 	 */
 	private MonitorInfo monitorInfo() throws IncompatibleThreadStateException {
 		// Note that this information should not be cached.
 		initJdwpRequest();
 		try {
 			JdwpReplyPacket replyPacket = requestVM(JdwpCommandPacket.OR_MONITOR_INFO, this);
 			switch (replyPacket.errorCode()) {
 				case JdwpReplyPacket.INVALID_THREAD:
 					throw new IncompatibleThreadStateException();
 				case JdwpReplyPacket.THREAD_NOT_SUSPENDED:
 					throw new IncompatibleThreadStateException();
 			}

 			defaultReplyErrorHandler(replyPacket.errorCode());

 			DataInputStream replyData = replyPacket.dataInStream();
 			MonitorInfo result = new MonitorInfo();
 			result.owner = ThreadReferenceImpl.read(this, replyData);
 			result.entryCount = readInt("entry count", replyData);
 			int nrOfWaiters = readInt("nr of waiters", replyData);
 			result.waiters = new ArrayList(nrOfWaiters);
 			for (int i = 0; i < nrOfWaiters; i++)
 				result.waiters.add(ThreadReferenceImpl.read(this, replyData));
 			return result;
 		} catch (IOException e) {
 			defaultIOExceptionHandler(e);
 			return null;
 		} finally {
 			handledJdwpRequest();
 		}
 	}

 	/**
 	 * @return Returns an ThreadReference for the thread, if any, which currently owns this object's monitor.
 	 */
 	public ThreadReference owningThread() throws IncompatibleThreadStateException {
 		return monitorInfo().owner;
 	}

 	/**
 	 * @return Returns the number times this object's monitor has been entered by the current owning thread.
 	 */
 	public int entryCount() throws IncompatibleThreadStateException {
 		return monitorInfo().entryCount;
 	}

 	/**
 	 * @return Returns a List containing a ThreadReference for each thread currently waiting for this object's monitor.
 	 */
 	public List waitingThreads() throws IncompatibleThreadStateException {
 		return monitorInfo().waiters;
 	}

 	/**
 	 * @return Returns the value of a given instance or static field in this object.
 	 */
 	public Value getValue(Field field) {
 		ArrayList list = new ArrayList(1);
 		list.add(field);
 		return (ValueImpl)getValues(list).get(field);
 	}

 	/**
 	 * @return Returns the value of multiple instance and/or static fields in this object.
 	 */
 	public Map getValues(List allFields) {
 		// Note that this information should not be cached.
 		initJdwpRequest();
 		try {
 			ByteArrayOutputStream outBytes = new ByteArrayOutputStream();
 			DataOutputStream outData = new DataOutputStream(outBytes);

 			/*
 			 * Distinguish static fields from non-static fields:
 			 * For static fields ReferencTypeImpl.getValues() must be used.
 			 */
 			Vector staticFields = new Vector();
 			Vector nonStaticFields = new Vector();

 			// Separate static and non-static fields.
 			int allFieldsSize = allFields.size();
 			for (int i = 0; i < allFieldsSize; i++) {
 				FieldImpl field = (FieldImpl)allFields.get(i);
 				checkVM(field);
 		   		if (field.isStatic())
 		   			staticFields.add(field);
 		   		else
 		   			nonStaticFields.add(field);
 			}

 			// First get values for the static fields.
 			Map resultMap  = referenceType().getValues(staticFields);

 			// Then get the values for the non-static fields.
 			int nonStaticFieldsSize = nonStaticFields.size();
 			write(this, outData);
 			writeInt(nonStaticFieldsSize, "size", outData);
 			for (int i = 0; i < nonStaticFieldsSize; i++) {
 				FieldImpl field = (FieldImpl)nonStaticFields.get(i);
 				field.write(this, outData);
 			}

 			JdwpReplyPacket replyPacket = requestVM(JdwpCommandPacket.OR_GET_VALUES, outBytes);
 			defaultReplyErrorHandler(replyPacket.errorCode());

 			DataInputStream replyData = replyPacket.dataInStream();
 			int nrOfElements = readInt("elements", replyData);
 			if (nrOfElements != nonStaticFieldsSize)
 				throw new InternalError("Retrieved a different number of values from the VM than requested.");

 			for (int i = 0; i < nrOfElements; i++) {
 				resultMap.put(nonStaticFields.get(i), ValueImpl.readWithTag(this, replyData));
 			}
 			return resultMap;
 		} catch (IOException e) {
 			defaultIOExceptionHandler(e);
 			return null;
 		} finally {
 			handledJdwpRequest();
 		}
 	}

 	/**
 	 * @return Returns the hash code value.
 	 */
 	public int hashCode() {
 		return fObjectID.hashCode();
 	}

 	/**
 	 * @return Returns true if two mirrors refer to the same entity in the target VM.
 	 * @see java.lang.Object#equals(Object)
 	 */
 	public boolean equals(Object object) {

 		return object != null
 			&& object.getClass().equals(this.getClass())
 			&& fObjectID.equals(((ObjectReferenceImpl)object).fObjectID)
 			&& virtualMachine().equals(((MirrorImpl)object).virtualMachine());
 	}

 	/**
 	 * @return Returns Jdwp version of given options.
 	 */
 	private int optionsToJdwpOptions(int options) {
 		int jdwpOptions = 0;
    		if ((options & INVOKE_SINGLE_THREADED) != 0)
    			jdwpOptions |= MethodImpl.INVOKE_SINGLE_THREADED_JDWP;
    		return jdwpOptions;
 	}

 	/**
 	 * Invokes the specified static Method in the target VM.
 	 * @return Returns a Value mirror of the invoked method's return value.
 	 */
 	public Value invokeMethod(ThreadReference thread, Method method, List arguments, int options) throws InvalidTypeException, ClassNotLoadedException, IncompatibleThreadStateException, InvocationException {
 	   	checkVM(thread);
 		checkVM(method);
 		ThreadReferenceImpl threadImpl = (ThreadReferenceImpl)thread;
 		MethodImpl methodImpl = (MethodImpl)method;

 		// Perform some checks for IllegalArgumentException.
 		if (!referenceType().visibleMethods().contains(method))
 			throw new IllegalArgumentException("Class does not contain given method.");
 		if (method.argumentTypeNames().size() != arguments.size())
 			throw new IllegalArgumentException("Number of arguments doesn't match.");
 		if (method.isConstructor() || method.isStaticInitializer())
 			throw new IllegalArgumentException("Method is constructor or intitializer.");
 		if ((options & INVOKE_NONVIRTUAL) != 0 && method.isAbstract())
 			throw new IllegalArgumentException("Method is abstract and can therefore not be invoked nonvirtual.");


 		initJdwpRequest();
 		try {
 			ByteArrayOutputStream outBytes = new ByteArrayOutputStream();
 			DataOutputStream outData = new DataOutputStream(outBytes);
 			write(this, outData);
 			threadImpl.write(this, outData);
 			((ReferenceTypeImpl)referenceType()).write(this, outData);
 			methodImpl.write(this, outData);

 			writeInt(arguments.size(), "size", outData);
 			Iterator iter = arguments.iterator();
 			while(iter.hasNext()) {
 				ValueImpl elt = (ValueImpl)iter.next();
 				if (elt != null) {
 					checkVM(elt);
 					elt.writeWithTag(this, outData);
 				} else {
 					ValueImpl.writeNullWithTag(this, outData);
 				}
 			}

 			writeInt(optionsToJdwpOptions(options),"options", MethodImpl.invokeOptionsVector(), outData);

 			JdwpReplyPacket replyPacket = requestVM(JdwpCommandPacket.OR_INVOKE_METHOD, outBytes);
 			switch (replyPacket.errorCode()) {
 				case JdwpReplyPacket.TYPE_MISMATCH:
 					throw new InvalidTypeException();
 				case JdwpReplyPacket.INVALID_CLASS:
 					throw new ClassNotLoadedException("One of the arguments of ObjectReference.invokeMethod()");
 				case JdwpReplyPacket.INVALID_THREAD:
 					throw new IncompatibleThreadStateException();
 				case JdwpReplyPacket.THREAD_NOT_SUSPENDED:
 					throw new IncompatibleThreadStateException();
 			}
 			defaultReplyErrorHandler(replyPacket.errorCode());
 			DataInputStream replyData = replyPacket.dataInStream();
 			ValueImpl value = ValueImpl.readWithTag(this, replyData);
 			ObjectReferenceImpl exception = ObjectReferenceImpl.readObjectRefWithTag(this, replyData);
 			if (exception != null)
 				throw new InvocationException(exception);
 			return value;
 		} catch (IOException e) {
 			defaultIOExceptionHandler(e);
 			return null;
 		} finally {
 			handledJdwpRequest();
 		}
 	}


 	/**
 	 * @return Returns if this object has been garbage collected in the target VM.
 	 */
 	public boolean isCollected() {
 		// Note that this information should not be cached.
 		initJdwpRequest();
 		try {
 			JdwpReplyPacket replyPacket = requestVM(JdwpCommandPacket.OR_IS_COLLECTED, this);
 			defaultReplyErrorHandler(replyPacket.errorCode());
 			DataInputStream replyData = replyPacket.dataInStream();
 			boolean result = readBoolean("is collected", replyData);
 			return result;
 		} catch (IOException e) {
 			defaultIOExceptionHandler(e);
 			return false;
 		} finally {
 			handledJdwpRequest();
 		}
 	}


 	/**
 	 * @return Returns the ReferenceType that mirrors the type of this object.
 	 */
 	public ReferenceType referenceType() {
 		initJdwpRequest();
 		try {
 			JdwpReplyPacket replyPacket = requestVM(JdwpCommandPacket.OR_REFERENCE_TYPE, this);
 			defaultReplyErrorHandler(replyPacket.errorCode());
 			DataInputStream replyData = replyPacket.dataInStream();
 			return ReferenceTypeImpl.readWithTypeTag(this, replyData);
 		} catch (IOException e) {
 			defaultIOExceptionHandler(e);
 			return null;
 		} finally {
 			handledJdwpRequest();
 		}
 	}

 	/**
 	 * @return Returns the Type that mirrors the type of this object.
 	 */
 	public Type type() {
 		return referenceType();
 	}

 	/**
 	 * Sets the value of a given instance or static field in this object.
 	 */
 	public void setValue(Field field, Value value) throws InvalidTypeException, ClassNotLoadedException {
 		// Note that this information should not be cached.
 		initJdwpRequest();
 		try {
 			ByteArrayOutputStream outBytes = new ByteArrayOutputStream();
 			DataOutputStream outData = new DataOutputStream(outBytes);
 			write(this, outData);
 			writeInt(1, "size", outData);	// We only set one field
 			checkVM(field);
 			((FieldImpl)field).write(this, outData);

 			if (value != null) {
 				checkVM(value);
 				((ValueImpl)value).write(this, outData);
 			} else {
 				ValueImpl.writeNull(this, outData);
 			}

 			JdwpReplyPacket replyPacket = requestVM(JdwpCommandPacket.OR_SET_VALUES, outBytes);
 			switch (replyPacket.errorCode()) {
 				case JdwpReplyPacket.TYPE_MISMATCH:
 					throw new InvalidTypeException();
 				case JdwpReplyPacket.INVALID_CLASS:
 					throw new ClassNotLoadedException(referenceType().name());
 			}
 			defaultReplyErrorHandler(replyPacket.errorCode());
 		} catch (IOException e) {
 			defaultIOExceptionHandler(e);
 		} finally {
 			handledJdwpRequest();
 		}
 	}

 	/**
 	 * @return Returns a unique identifier for this ObjectReference.
 	 */
 	public long uniqueID() {
 		if (isCollected())
 			throw new ObjectCollectedException();
 		return fObjectID.value();
 	}

 	/**
 	 * @return Returns string with value of ID.
 	 */
 	public String idString() {
 		return "(id=" + fObjectID + ")";
 	}

 	/**
 	 * @return Returns description of Mirror object.
 	 */
 	public String toString() {
 		try {
 			return type().toString() + " " + idString();
 		} catch (ObjectCollectedException e) {
 			return "(Garbage Collected) ObjectReference " + idString();
 		} catch (Exception e) {
 			return fDescription;
 		}
 	}

 	/**
 	 * @return Reads JDWP representation and returns new instance.
 	 */
 	public static ObjectReferenceImpl readObjectRefWithoutTag(MirrorImpl target, DataInputStream in) throws IOException {
 		VirtualMachineImpl vmImpl = target.virtualMachineImpl();
 		JdwpObjectID ID = new JdwpObjectID(vmImpl);
 		ID.read(in);
 		if (target.fVerboseWriter != null)
 			target.fVerboseWriter.println("objectReference", ID.value());

 		if (ID.isNull())
 			return null;

 		ObjectReferenceImpl mirror = new ObjectReferenceImpl(vmImpl, ID);
 		return mirror;
 	}

 	/**
 	 * @return Reads JDWP representation and returns new instance.
 	 */
 	public static ObjectReferenceImpl readObjectRefWithTag(MirrorImpl target, DataInputStream in) throws IOException {
 		byte tag = target.readByte("object tag", JdwpID.tagMap(), in);
 		switch (tag) {
 	   		case 0:
 				return null;
 			case ObjectReferenceImpl.tag:
 				return ObjectReferenceImpl.readObjectRefWithoutTag(target, in);
 			case ArrayReferenceImpl.tag:
 				return ArrayReferenceImpl.read(target, in);
 			case ClassLoaderReferenceImpl.tag:
 				return ClassLoaderReferenceImpl.read(target, in);
 			case ClassObjectReferenceImpl.tag:
 				return ClassObjectReferenceImpl.read(target, in);
 			case StringReferenceImpl.tag:
 				return StringReferenceImpl.read(target, in);
 			case ThreadGroupReferenceImpl.tag:
 				return ThreadGroupReferenceImpl.read(target, in);
 			case ThreadReferenceImpl.tag:
 				return ThreadReferenceImpl.read(target, in);
    	   	}
 		throw new InternalException("Invalid ObjectID tag encountered: " + tag);
 	}

 	/**
 	 * Writes JDWP representation without tag.
 	 */
 	public void write(MirrorImpl target, DataOutputStream out) throws IOException {
 		fObjectID.write(out);
 		if (target.fVerboseWriter != null)
 			target.fVerboseWriter.println("objectReference", fObjectID.value());
 	}
 }
	package org.eclipse.jdi.internal;

	/*
	* (c) Copyright IBM Corp. 2000, 2001.
	* All Rights Reserved.
	*/

	import com.sun.jdi.*;
	import com.sun.jdi.connect.*;
	import com.sun.jdi.event.*;
	import com.sun.jdi.request.*;
	import org.eclipse.jdi.internal.connect.*;
	import org.eclipse.jdi.internal.request.*;
	import org.eclipse.jdi.internal.event.*;
	import org.eclipse.jdi.internal.jdwp.*;
	import org.eclipse.jdi.internal.spy.*;
	import java.util.*;
	import java.io.*;

	/**
	* this class implements the corresponding interfaces
	* declared by the JDI specification. See the com.sun.jdi package
	* for more information.
	*
	*/
	public class ObjectReferenceImpl extends ValueImpl implements ObjectReference {
	/** JDWP Tag. */
	public static final byte tag = JdwpID.OBJECT_TAG;

	/** ObjectID of object that corresponds to this reference. */
	private JdwpObjectID fObjectID;

	/**
	* Creates new ObjectReferenceImpl.
	*/
	public ObjectReferenceImpl(VirtualMachineImpl vmImpl, JdwpObjectID objectID) {
	this("ObjectReference", vmImpl, objectID);
	}

	/**
	* Creates new ObjectReferenceImpl.
	*/
	public ObjectReferenceImpl(String description, VirtualMachineImpl vmImpl, JdwpObjectID objectID) {
	super(description, vmImpl);
	fObjectID = objectID;
	}

	/**
	* @returns tag.
	*/
	public byte getTag() {
	return tag;
	}

	/**
	* @return Returns Jdwp Object ID.
	*/
	public JdwpObjectID getObjectID() {
	return fObjectID;
	}

	/**
	* Prevents garbage collection for this object.
	*/
	public void disableCollection() {
	initJdwpRequest();
	try {
	JdwpReplyPacket replyPacket = requestVM(JdwpCommandPacket.OR_DISABLE_COLLECTION, this);
	defaultReplyErrorHandler(replyPacket.errorCode());
	} finally {
	handledJdwpRequest();
	}
	}

	/**
	* Permits garbage collection for this object.
	*/
	public void enableCollection() {
	initJdwpRequest();
	try {
	JdwpReplyPacket replyPacket = requestVM(JdwpCommandPacket.OR_ENABLE_COLLECTION, this);
	defaultReplyErrorHandler(replyPacket.errorCode());
	} finally {
	handledJdwpRequest();
	}
	}

	/**
	* Inner class used to return monitor info.
	*/
	private class MonitorInfo {
	ThreadReferenceImpl owner;
	int entryCount;
	ArrayList waiters;
	}

	/**
	* @return Returns monitor info.
	*/
	private MonitorInfo monitorInfo() throws IncompatibleThreadStateException {
	// Note that this information should not be cached.
	initJdwpRequest();
	try {
	JdwpReplyPacket replyPacket = requestVM(JdwpCommandPacket.OR_MONITOR_INFO, this);
	switch (replyPacket.errorCode()) {
	case JdwpReplyPacket.INVALID_THREAD:
	throw new IncompatibleThreadStateException();
	case JdwpReplyPacket.THREAD_NOT_SUSPENDED:
	throw new IncompatibleThreadStateException();
	}

	defaultReplyErrorHandler(replyPacket.errorCode());

	DataInputStream replyData = replyPacket.dataInStream();
	MonitorInfo result = new MonitorInfo();
	result.owner = ThreadReferenceImpl.read(this, replyData);
	result.entryCount = readInt("entry count", replyData);
	int nrOfWaiters = readInt("nr of waiters", replyData);
	result.waiters = new ArrayList(nrOfWaiters);
	for (int i = 0; i < nrOfWaiters; i++)
	result.waiters.add(ThreadReferenceImpl.read(this, replyData));
	return result;
	} catch (IOException e) {
	defaultIOExceptionHandler(e);
	return null;
	} finally {
	handledJdwpRequest();
	}
	}

	/**
	* @return Returns an ThreadReference for the thread, if any, which currently owns this object's monitor.
	*/
	public ThreadReference owningThread() throws IncompatibleThreadStateException {
	return monitorInfo().owner;
	}

	/**
	* @return Returns the number times this object's monitor has been entered by the current owning thread.
	*/
	public int entryCount() throws IncompatibleThreadStateException {
	return monitorInfo().entryCount;
	}

	/**
	* @return Returns a List containing a ThreadReference for each thread currently waiting for this object's monitor.
	*/
	public List waitingThreads() throws IncompatibleThreadStateException {
	return monitorInfo().waiters;
	}

	/**
	* @return Returns the value of a given instance or static field in this object.
	*/
	public Value getValue(Field field) {
	ArrayList list = new ArrayList(1);
	list.add(field);
	return (ValueImpl)getValues(list).get(field);
	}

	/**
	* @return Returns the value of multiple instance and/or static fields in this object.
	*/
	public Map getValues(List allFields) {
	// Note that this information should not be cached.
	initJdwpRequest();
	try {
	ByteArrayOutputStream outBytes = new ByteArrayOutputStream();
	DataOutputStream outData = new DataOutputStream(outBytes);

	/*
	* Distinguish static fields from non-static fields:
	* For static fields ReferencTypeImpl.getValues() must be used.
	*/
	Vector staticFields = new Vector();
	Vector nonStaticFields = new Vector();

	// Separate static and non-static fields.
	int allFieldsSize = allFields.size();
	for (int i = 0; i < allFieldsSize; i++) {
	FieldImpl field = (FieldImpl)allFields.get(i);
	checkVM(field);
	if (field.isStatic())
	staticFields.add(field);
	else
	nonStaticFields.add(field);
	}

	// First get values for the static fields.
	Map resultMap = referenceType().getValues(staticFields);

	// Then get the values for the non-static fields.
	int nonStaticFieldsSize = nonStaticFields.size();
	write(this, outData);
	writeInt(nonStaticFieldsSize, "size", outData);
	for (int i = 0; i < nonStaticFieldsSize; i++) {
	FieldImpl field = (FieldImpl)nonStaticFields.get(i);
	field.write(this, outData);
	}

	JdwpReplyPacket replyPacket = requestVM(JdwpCommandPacket.OR_GET_VALUES, outBytes);
	defaultReplyErrorHandler(replyPacket.errorCode());

	DataInputStream replyData = replyPacket.dataInStream();
	int nrOfElements = readInt("elements", replyData);
	if (nrOfElements != nonStaticFieldsSize)
	throw new InternalError("Retrieved a different number of values from the VM than requested.");

	for (int i = 0; i < nrOfElements; i++) {
	resultMap.put(nonStaticFields.get(i), ValueImpl.readWithTag(this, replyData));
	}
	return resultMap;
	} catch (IOException e) {
	defaultIOExceptionHandler(e);
	return null;
	} finally {
	handledJdwpRequest();
	}
	}

	/**
	* @return Returns the hash code value.
	*/
	public int hashCode() {
	return fObjectID.hashCode();
	}

	/**
	* @return Returns true if two mirrors refer to the same entity in the target VM.
	* @see java.lang.Object#equals(Object)
	*/
	public boolean equals(Object object) {

	return object != null
	&& object.getClass().equals(this.getClass())
	&& fObjectID.equals(((ObjectReferenceImpl)object).fObjectID)
	&& virtualMachine().equals(((MirrorImpl)object).virtualMachine());
	}

	/**
	* @return Returns Jdwp version of given options.
	*/
	private int optionsToJdwpOptions(int options) {
	int jdwpOptions = 0;
	if ((options & INVOKE_SINGLE_THREADED) != 0)
	jdwpOptions \|= MethodImpl.INVOKE_SINGLE_THREADED_JDWP;
	return jdwpOptions;
	}

	/**
	* Invokes the specified static Method in the target VM.
	* @return Returns a Value mirror of the invoked method's return value.
	*/
	public Value invokeMethod(ThreadReference thread, Method method, List arguments, int options) throws InvalidTypeException, ClassNotLoadedException, IncompatibleThreadStateException, InvocationException {
	checkVM(thread);
	checkVM(method);
	ThreadReferenceImpl threadImpl = (ThreadReferenceImpl)thread;
	MethodImpl methodImpl = (MethodImpl)method;

	// Perform some checks for IllegalArgumentException.
	if (!referenceType().visibleMethods().contains(method))
	throw new IllegalArgumentException("Class does not contain given method.");
	if (method.argumentTypeNames().size() != arguments.size())
	throw new IllegalArgumentException("Number of arguments doesn't match.");
	if (method.isConstructor() \|\| method.isStaticInitializer())
	throw new IllegalArgumentException("Method is constructor or intitializer.");
	if ((options & INVOKE_NONVIRTUAL) != 0 && method.isAbstract())
	throw new IllegalArgumentException("Method is abstract and can therefore not be invoked nonvirtual.");


	initJdwpRequest();
	try {
	ByteArrayOutputStream outBytes = new ByteArrayOutputStream();
	DataOutputStream outData = new DataOutputStream(outBytes);
	write(this, outData);
	threadImpl.write(this, outData);
	((ReferenceTypeImpl)referenceType()).write(this, outData);
	methodImpl.write(this, outData);

	writeInt(arguments.size(), "size", outData);
	Iterator iter = arguments.iterator();
	while(iter.hasNext()) {
	ValueImpl elt = (ValueImpl)iter.next();
	if (elt != null) {
	checkVM(elt);
	elt.writeWithTag(this, outData);
	} else {
	ValueImpl.writeNullWithTag(this, outData);
	}
	}

	writeInt(optionsToJdwpOptions(options),"options", MethodImpl.invokeOptionsVector(), outData);

	JdwpReplyPacket replyPacket = requestVM(JdwpCommandPacket.OR_INVOKE_METHOD, outBytes);
	switch (replyPacket.errorCode()) {
	case JdwpReplyPacket.TYPE_MISMATCH:
	throw new InvalidTypeException();
	case JdwpReplyPacket.INVALID_CLASS:
	throw new ClassNotLoadedException("One of the arguments of ObjectReference.invokeMethod()");
	case JdwpReplyPacket.INVALID_THREAD:
	throw new IncompatibleThreadStateException();
	case JdwpReplyPacket.THREAD_NOT_SUSPENDED:
	throw new IncompatibleThreadStateException();
	}
	defaultReplyErrorHandler(replyPacket.errorCode());
	DataInputStream replyData = replyPacket.dataInStream();
	ValueImpl value = ValueImpl.readWithTag(this, replyData);
	ObjectReferenceImpl exception = ObjectReferenceImpl.readObjectRefWithTag(this, replyData);
	if (exception != null)
	throw new InvocationException(exception);
	return value;
	} catch (IOException e) {
	defaultIOExceptionHandler(e);
	return null;
	} finally {
	handledJdwpRequest();
	}
	}


	/**
	* @return Returns if this object has been garbage collected in the target VM.
	*/
	public boolean isCollected() {
	// Note that this information should not be cached.
	initJdwpRequest();
	try {
	JdwpReplyPacket replyPacket = requestVM(JdwpCommandPacket.OR_IS_COLLECTED, this);
	defaultReplyErrorHandler(replyPacket.errorCode());
	DataInputStream replyData = replyPacket.dataInStream();
	boolean result = readBoolean("is collected", replyData);
	return result;
	} catch (IOException e) {
	defaultIOExceptionHandler(e);
	return false;
	} finally {
	handledJdwpRequest();
	}
	}


	/**
	* @return Returns the ReferenceType that mirrors the type of this object.
	*/
	public ReferenceType referenceType() {
	initJdwpRequest();
	try {
	JdwpReplyPacket replyPacket = requestVM(JdwpCommandPacket.OR_REFERENCE_TYPE, this);
	defaultReplyErrorHandler(replyPacket.errorCode());
	DataInputStream replyData = replyPacket.dataInStream();
	return ReferenceTypeImpl.readWithTypeTag(this, replyData);
	} catch (IOException e) {
	defaultIOExceptionHandler(e);
	return null;
	} finally {
	handledJdwpRequest();
	}
	}

	/**
	* @return Returns the Type that mirrors the type of this object.
	*/
	public Type type() {
	return referenceType();
	}

	/**
	* Sets the value of a given instance or static field in this object.
	*/
	public void setValue(Field field, Value value) throws InvalidTypeException, ClassNotLoadedException {
	// Note that this information should not be cached.
	initJdwpRequest();
	try {
	ByteArrayOutputStream outBytes = new ByteArrayOutputStream();
	DataOutputStream outData = new DataOutputStream(outBytes);
	write(this, outData);
	writeInt(1, "size", outData); // We only set one field
	checkVM(field);
	((FieldImpl)field).write(this, outData);

	if (value != null) {
	checkVM(value);
	((ValueImpl)value).write(this, outData);
	} else {
	ValueImpl.writeNull(this, outData);
	}

	JdwpReplyPacket replyPacket = requestVM(JdwpCommandPacket.OR_SET_VALUES, outBytes);
	switch (replyPacket.errorCode()) {
	case JdwpReplyPacket.TYPE_MISMATCH:
	throw new InvalidTypeException();
	case JdwpReplyPacket.INVALID_CLASS:
	throw new ClassNotLoadedException(referenceType().name());
	}
	defaultReplyErrorHandler(replyPacket.errorCode());
	} catch (IOException e) {
	defaultIOExceptionHandler(e);
	} finally {
	handledJdwpRequest();
	}
	}

	/**
	* @return Returns a unique identifier for this ObjectReference.
	*/
	public long uniqueID() {
	if (isCollected())
	throw new ObjectCollectedException();
	return fObjectID.value();
	}

	/**
	* @return Returns string with value of ID.
	*/
	public String idString() {
	return "(id=" + fObjectID + ")";
	}

	/**
	* @return Returns description of Mirror object.
	*/
	public String toString() {
	try {
	return type().toString() + " " + idString();
	} catch (ObjectCollectedException e) {
	return "(Garbage Collected) ObjectReference " + idString();
	} catch (Exception e) {
	return fDescription;
	}
	}

	/**
	* @return Reads JDWP representation and returns new instance.
	*/
	public static ObjectReferenceImpl readObjectRefWithoutTag(MirrorImpl target, DataInputStream in) throws IOException {
	VirtualMachineImpl vmImpl = target.virtualMachineImpl();
	JdwpObjectID ID = new JdwpObjectID(vmImpl);
	ID.read(in);
	if (target.fVerboseWriter != null)
	target.fVerboseWriter.println("objectReference", ID.value());

	if (ID.isNull())
	return null;

	ObjectReferenceImpl mirror = new ObjectReferenceImpl(vmImpl, ID);
	return mirror;
	}

	/**
	* @return Reads JDWP representation and returns new instance.
	*/
	public static ObjectReferenceImpl readObjectRefWithTag(MirrorImpl target, DataInputStream in) throws IOException {
	byte tag = target.readByte("object tag", JdwpID.tagMap(), in);
	switch (tag) {
	case 0:
	return null;
	case ObjectReferenceImpl.tag:
	return ObjectReferenceImpl.readObjectRefWithoutTag(target, in);
	case ArrayReferenceImpl.tag:
	return ArrayReferenceImpl.read(target, in);
	case ClassLoaderReferenceImpl.tag:
	return ClassLoaderReferenceImpl.read(target, in);
	case ClassObjectReferenceImpl.tag:
	return ClassObjectReferenceImpl.read(target, in);
	case StringReferenceImpl.tag:
	return StringReferenceImpl.read(target, in);
	case ThreadGroupReferenceImpl.tag:
	return ThreadGroupReferenceImpl.read(target, in);
	case ThreadReferenceImpl.tag:
	return ThreadReferenceImpl.read(target, in);
	}
	throw new InternalException("Invalid ObjectID tag encountered: " + tag);
	}

	/**
	* Writes JDWP representation without tag.
	*/
	public void write(MirrorImpl target, DataOutputStream out) throws IOException {
	fObjectID.write(out);
	if (target.fVerboseWriter != null)
	target.fVerboseWriter.println("objectReference", fObjectID.value());
	}
	}