objectstreamclass.java

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		} else {
		    // For each declared persistent field, look for an actual
		    // reflected Field. If there is one, make sure it's the correct
		    // type and cache it in the ObjectStreamClass for that field.
		    for (int j = fields.length-1; j >= 0; j--) {
			try {
                            Field reflField = cl.getDeclaredField(fields[j].getName());
			    if (fields[j].getType() == reflField.getType()) {
				reflField.setAccessible(true);
				fields[j].setField(reflField);
			    }
			} catch (NoSuchFieldException e) {
			    // Nothing to do
			}
		    }
		}
	        return null;
	    }
	    });

	    if (fields.length > 1)
		Arrays.sort(fields);

	    /* Set up field data for use while writing using the API api. */
	    computeFieldInfo();
	}

        /* Get the serialVersionUID from the class.
         * It uses the access override mechanism so make sure
         * the field objects is only used here.
         *
         * NonSerializable classes have a serialVerisonUID of 0L.
         */
         if (isNonSerializable()) {
             suid = 0L;
         } else {
             // Lookup special Serializable members using reflection.
             AccessController.doPrivileged(new PrivilegedAction() {
                public Object run() {
                if (forProxyClass) {
                    // proxy classes always have serialVersionUID of 0L
                    suid = 0L;
                } else {
	            try {
                        final Field f = cl.getDeclaredField("serialVersionUID");
	                int mods = f.getModifiers();
			// SerialBug 5:  static final SUID should be read
	                if (Modifier.isStatic(mods) && Modifier.isFinal(mods) ) {
                            f.setAccessible(true);
		            suid = f.getLong(cl);
			    // SerialBug 2: should be computed after writeObject
			    // actualSuid = computeStructuralUID(cl);
	                } else {
		            suid = _computeSerialVersionUID(cl);
	                    // SerialBug 2: should be computed after writeObject
	                    // actualSuid = computeStructuralUID(cl);
	                }
	            } catch (NoSuchFieldException ex) {
	                suid = _computeSerialVersionUID(cl);
	                // SerialBug 2: should be computed after writeObject
	                // actualSuid = computeStructuralUID(cl);
                    } catch (IllegalAccessException ex) {
                        suid = _computeSerialVersionUID(cl);
                    }
	        }

                writeReplaceObjectMethod = ObjectStreamClass.getInheritableMethod(cl, 
		    "writeReplace", noTypesList, Object.class);

                readResolveObjectMethod = ObjectStreamClass.getInheritableMethod(cl, 
		    "readResolve", noTypesList, Object.class);
	
		if (externalizable) 
		    cons = getExternalizableConstructor(cl) ;
		else
		    cons = getSerializableConstructor(cl) ;

                if (serializable && !forProxyClass) {
	            /* Look for the writeObject method
	             * Set the accessible flag on it here. ObjectOutputStream
	             * will call it as necessary.
	             */
		    writeObjectMethod = getPrivateMethod( cl, "writeObject",
			new Class[] { java.io.ObjectOutputStream.class }, Void.TYPE ) ;
		    readObjectMethod = getPrivateMethod( cl, "readObject",
			new Class[] { java.io.ObjectInputStream.class }, Void.TYPE ) ;
	        }
	        return null;
	    }
	  });
	}

        // This call depends on a lot of information computed above!
        actualSuid = ObjectStreamClass.computeStructuralUID(this, cl);

        // If we have a write object method, precompute the
        // RMI-IIOP stream format version 2 optional data
        // repository ID.  
        if (hasWriteObject())
            rmiiiopOptionalDataRepId = computeRMIIIOPOptionalDataRepId();

        // This must be done last.
        initialized = true;
      }
    }

    /**
     * Returns non-static private method with given signature defined by given
     * class, or null if none found.  Access checks are disabled on the
     * returned method (if any).
     */
    private static Method getPrivateMethod(Class cl, String name, 
					   Class[] argTypes,
					   Class returnType)
    {
	try {
	    Method meth = cl.getDeclaredMethod(name, argTypes);
	    meth.setAccessible(true);
	    int mods = meth.getModifiers();
	    return ((meth.getReturnType() == returnType) &&
		    ((mods & Modifier.STATIC) == 0) &&
		    ((mods & Modifier.PRIVATE) != 0)) ? meth : null;
	} catch (NoSuchMethodException ex) {
	    return null;
	}
    }

    // Specific to RMI-IIOP
    /**
     * Java to IDL ptc-02-01-12 1.5.1
     *
     * "The rep_id string passed to the start_value method must be
     * 'RMI:org.omg.custom.class:hashcode:suid' where class is the
     * fully-qualified name of the class whose writeObject method
     * is being invoked and hashcode and suid are the class's hashcode
     * and SUID."
     */
    private String computeRMIIIOPOptionalDataRepId() {

        StringBuffer sbuf = new StringBuffer("RMI:org.omg.custom.");
        sbuf.append(RepositoryId.convertToISOLatin1(this.getName()));
        sbuf.append(':');
        sbuf.append(this.getActualSerialVersionUIDStr());
        sbuf.append(':');
        sbuf.append(this.getSerialVersionUIDStr());

        return sbuf.toString();
    }

    /**
     * This will return null if there is no writeObject method.
     */
    public final String getRMIIIOPOptionalDataRepId() {
        return rmiiiopOptionalDataRepId;
    }

    /*
     * Create an empty ObjectStreamClass for a class about to be read.
     * This is separate from read so ObjectInputStream can assign the
     * wire handle early, before any nested ObjectStreamClass might
     * be read.
     */
    ObjectStreamClass(String n, long s) {
	name = n;
	suid = s;
	superclass = null;
    }

    private static Object[] translateFields(Object objs[])
        throws NoSuchFieldException {
        try{
            java.io.ObjectStreamField fields[] = (java.io.ObjectStreamField[])objs;
            Object translation[] = null;
                       
            if (translatedFields == null)
                translatedFields = new Hashtable();
                       
            translation = (Object[])translatedFields.get(fields);
                       
            if (translation != null)
                return translation;
            else {
                Class osfClass = Class.forName("com.sun.corba.se.impl.io.ObjectStreamField");
                translation = (Object[])java.lang.reflect.Array.newInstance(osfClass, objs.length);
                Object arg[] = new Object[2];
                Class types[] = {String.class, Class.class};
                Constructor constructor = osfClass.getDeclaredConstructor(types);
                for (int i = fields.length -1; i >= 0; i--){
                    arg[0] = fields[i].getName();
                    arg[1] = fields[i].getType();
                       
                    translation[i] = constructor.newInstance(arg);
                }
                translatedFields.put(fields, translation);
                       
            }

            return (Object[])translation;
        }
        catch(Throwable t){
            NoSuchFieldException nsfe = new NoSuchFieldException();
	    nsfe.initCause( t ) ;
	    throw nsfe ;
        }
    }

    /*
     * Set the class this version descriptor matches.
     * The base class name and serializable hash must match.
     * Fill in the reflected Fields that will be used
     * for reading.
     */
    final void setClass(Class cl) throws InvalidClassException {

	if (cl == null) {
	    localClassDesc = null;
	    ofClass = null;
	    computeFieldInfo();
	    return;
	}

	localClassDesc = lookupInternal(cl);
	if (localClassDesc == null)
	    // XXX I18N, logging needed
	    throw new InvalidClassException(cl.getName(),
					    "Local class not compatible");
	if (suid != localClassDesc.suid) {

            /* Check for exceptional cases that allow mismatched suid. */

            /* Allow adding Serializable or Externalizable
             * to a later release of the class.
             */
            boolean addedSerialOrExtern =
                isNonSerializable() || localClassDesc.isNonSerializable();

	    /* Disregard the serialVersionUID of an array
	     * when name and cl.Name differ. If resolveClass() returns
	     * an array with a different package name,
	     * the serialVersionUIDs will not match since the fully
	     * qualified array class is used in the
	     * computation of the array's serialVersionUID. There is
	     * no way to set a permanent serialVersionUID for an array type.
	     */

            boolean arraySUID = (cl.isArray() && ! cl.getName().equals(name));

            if (! arraySUID && ! addedSerialOrExtern ) {
		// XXX I18N, logging needed
		throw new InvalidClassException(cl.getName(),
						"Local class not compatible:" +
						" stream classdesc serialVersionUID=" + suid +
						" local class serialVersionUID=" + localClassDesc.suid);
	    }
        }

	/* compare the class names, stripping off package names. */
	if (! compareClassNames(name, cl.getName(), '.'))
	    // XXX I18N, logging needed
            throw new InvalidClassException(cl.getName(),
                         "Incompatible local class name. " +
                         "Expected class name compatible with " +
                         name);

	/*
	 * Test that both implement either serializable or externalizable.
	 */

	// The next check is more generic, since it covers the
	// Proxy case, the JDK 1.3 serialization code has
	// both checks
        //if ((serializable && localClassDesc.externalizable) ||
        //    (externalizable && localClassDesc.serializable))
        //    throw new InvalidClassException(localCl.getName(),
        //            "Serializable is incompatible with Externalizable");

        if ((serializable != localClassDesc.serializable) ||
            (externalizable != localClassDesc.externalizable) ||
	    (!serializable && !externalizable))

	    // XXX I18N, logging needed
	    throw new InvalidClassException(cl.getName(),
					    "Serialization incompatible with Externalization");

	/* Set up the reflected Fields in the class where the value of each
	 * field in this descriptor should be stored.
	 * Each field in this ObjectStreamClass (the source) is located (by
	 * name) in the ObjectStreamClass of the class(the destination).
	 * In the usual (non-versioned case) the field is in both
	 * descriptors and the types match, so the reflected Field is copied.
	 * If the type does not match, a InvalidClass exception is thrown.
	 * If the field is not present in the class, the reflected Field
	 * remains null so the field will be read but discarded.
	 * If extra fields are present in the class they are ignored. Their
	 * values will be set to the default value by the object allocator.
	 * Both the src and dest field list are sorted by type and name.
	 */

	ObjectStreamField[] destfield =
	    (ObjectStreamField[])localClassDesc.fields;
	ObjectStreamField[] srcfield =
	    (ObjectStreamField[])fields;

	int j = 0;
    nextsrc:
	for (int i = 0; i < srcfield.length; i++ ) {
	    /* Find this field in the dest*/
	    for (int k = j; k < destfield.length; k++) {
		if (srcfield[i].getName().equals(destfield[k].getName())) {
		    /* found match */
		    if (srcfield[i].isPrimitive() &&
			!srcfield[i].typeEquals(destfield[k])) {
			// XXX I18N, logging needed
			throw new InvalidClassException(cl.getName(),
							"The type of field " +
							srcfield[i].getName() +
							" of class " + name +
							" is incompatible.");
		    }

		    /* Skip over any fields in the dest that are not in the src */
		    j = k;

		    srcfield[i].setField(destfield[j].getField());
		    // go on to the next source field
		    continue nextsrc;
		}
	    }
	}

	/* Set up field data for use while reading from the input stream. */
	computeFieldInfo();

	/* Remember the class this represents */
	ofClass = cl;

        /* get the cache of these methods from the local class
         * implementation.
         */
        readObjectMethod = localClassDesc.readObjectMethod;
        readResolveObjectMethod = localClassDesc.readResolveObjectMethod;
    }

    /* Compare the base class names of streamName and localName.
     *
     * @return  Return true iff the base class name compare.
     * @parameter streamName	Fully qualified class name.
     * @parameter localName	Fully qualified class name.
     * @parameter pkgSeparator	class names use either '.' or '/'.
     *
     * Only compare base class name to allow package renaming.
     */
    static boolean compareClassNames(String streamName,
				     String localName,
				     char pkgSeparator) {
	/* compare the class names, stripping off package names. */
	int streamNameIndex = streamName.lastIndexOf(pkgSeparator);
	if (streamNameIndex < 0)
	    streamNameIndex = 0;

	int localNameIndex = localName.lastIndexOf(pkgSeparator);
	if (localNameIndex < 0)
	    localNameIndex = 0;

	return streamName.regionMatches(false, streamNameIndex,
					localName, localNameIndex,
					streamName.length() - streamNameIndex);
    }

    /*
     * Compare the types of two class descriptors.
     * They match if they have the same class name and suid
     */
    final boolean typeEquals(ObjectStreamClass other) {
	return (suid == other.suid) &&
	    compareClassNames(name, other.name, '.');
    }

    /*
     * Return the superclass descriptor of this descriptor.
     */
    final void setSuperclass(ObjectStreamClass s) {
	superclass = s;
    }

    /*
     * Return the superclass descriptor of this descriptor.
     */
    final ObjectStreamClass getSuperclass() {
	return superclass;
    }

    /**
     * Return whether the class has a readObject method
     */
    final boolean hasReadObject() {
        return readObjectMethod != null;
    }

    /*
     * Return whether the class has a writeObject method
     */
    final boolean hasWriteObject() {
	return writeObjectMethod != null ;
    }

    /**
     * Returns when or not this class should be custom
     * marshaled (use chunking).  This should happen if
     * it is Externalizable OR if it or
     * any of its superclasses has a writeObject method,
     */
    final boolean isCustomMarshaled() {
	return (hasWriteObject() || isExternalizable())
            || (superclass != null && superclass.isCustomMarshaled());
    }

    /*
     * Return true if all instances of 'this' Externalizable class
     * are written in block-data mode from the stream that 'this' was read
     * from. <p>
     *
     * In JDK 1.1, all Externalizable instances are not written
     * in block-data mode.
     * In JDK 1.2, all Externalizable instances, by default, are written
     * in block-data mode and the Externalizable instance is terminated with
     * tag TC_ENDBLOCKDATA. Change enabled the ability to skip Externalizable
     * instances.
     *
     * IMPLEMENTATION NOTE:
     *   This should have been a mode maintained per stream; however,
     *   for compatibility reasons, it was only possible to record
     *   this change per class. All Externalizable classes within
     *   a given stream should either have this mode enabled or
     *   disabled. This is enforced by not allowing the PROTOCOL_VERSION
     *   of a stream to he changed after any objects have been written.
     *
     * @see ObjectOutputStream#useProtocolVersion
     * @see ObjectStreamConstants#PROTOCOL_VERSION_1
     * @see ObjectStreamConstants#PROTOCOL_VERSION_2
     *
     * @since JDK 1.2
     */
    boolean hasExternalizableBlockDataMode() {
	return hasExternalizableBlockData;
    }

    /**
     * Creates a new instance of the represented class.  If the class is
     * externalizable, invokes its public no-arg constructor; otherwise, if the
     * class is serializable, invokes the no-arg constructor of the first
     * non-serializable superclass.  Throws UnsupportedOperationException if
     * this class descriptor is not associated with a class, if the associated
     * class is non-serializable or if the appropriate no-arg constructor is
     * inaccessible/unavailable.
     */