jdk/src/share/classes/com/sun/tools/jdi/ObjectReferenceImpl.java
changeset 2 90ce3da70b43
child 51 6fe31bc95bbc
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/jdk/src/share/classes/com/sun/tools/jdi/ObjectReferenceImpl.java	Sat Dec 01 00:00:00 2007 +0000
@@ -0,0 +1,603 @@
+/*
+ * 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;
+    }
+}