/*

 * Copyright (c) 1997, 2008, Oracle and/or its affiliates. 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.  Oracle designates this

 * particular file as subject to the "Classpath" exception as provided

 * by Oracle 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 Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

 * or visit www.oracle.com if you need additional information or have any

 * questions.

 */

/*

 * The Original Code is HAT. The Initial Developer of the

 * Original Code is Bill Foote, with contributions from others

 * at JavaSoft/Sun.

 */

package com.sun.tools.hat.internal.model;

import java.io.IOException;

import com.sun.tools.hat.internal.parser.ReadBuffer;

/**

 * @author      Bill Foote

 */

public class JavaObjectArray extends JavaLazyReadObject {

    private Object clazz;  // Long before resolve, the class after resolve

    public JavaObjectArray(long classID, long offset) {

        super(offset);

        this.clazz = makeId(classID);

    }

    public JavaClass getClazz() {

        return (JavaClass) clazz;

    }

    public void resolve(Snapshot snapshot) {

        if (clazz instanceof JavaClass) {

            return;

        }

        long classID = getIdValue((Number)clazz);

        if (snapshot.isNewStyleArrayClass()) {

            // Modern heap dumps do this

            JavaThing t = snapshot.findThing(classID);

            if (t instanceof JavaClass) {

                clazz = (JavaClass) t;

            }

        }

        if (!(clazz instanceof JavaClass)) {

            JavaThing t = snapshot.findThing(classID);

            if (t != null && t instanceof JavaClass) {

                JavaClass el = (JavaClass) t;

                String nm = el.getName();

                if (!nm.startsWith("[")) {

                    nm = "L" + el.getName() + ";";

                }

                clazz = snapshot.getArrayClass(nm);

            }

        }

        if (!(clazz instanceof JavaClass)) {

            clazz = snapshot.getOtherArrayType();

        }

        ((JavaClass)clazz).addInstance(this);

        super.resolve(snapshot);

    }

    public JavaThing[] getValues() {

        return getElements();

    }

    public JavaThing[] getElements() {

        Snapshot snapshot = getClazz().getSnapshot();

        byte[] data = getValue();

        final int idSize = snapshot.getIdentifierSize();

        final int numElements = data.length / idSize;

        JavaThing[] elements = new JavaThing[numElements];

        int index = 0;

        for (int i = 0; i < elements.length; i++) {

            long id = objectIdAt(index, data);

            index += idSize;

            elements[i] = snapshot.findThing(id);

        }

        return elements;

    }

    public int compareTo(JavaThing other) {

        if (other instanceof JavaObjectArray) {

            return 0;

        }

        return super.compareTo(other);

    }

    public int getLength() {

        return getValueLength() / getClazz().getIdentifierSize();

    }

    public void visitReferencedObjects(JavaHeapObjectVisitor v) {

        super.visitReferencedObjects(v);

        JavaThing[] elements = getElements();

        for (int i = 0; i < elements.length; i++) {

            if (elements[i] != null && elements[i] instanceof JavaHeapObject) {

                v.visit((JavaHeapObject) elements[i]);

            }

        }

    }

    /**

     * Describe the reference that this thing has to target.  This will only

     * be called if target is in the array returned by getChildrenForRootset.

     */

    public String describeReferenceTo(JavaThing target, Snapshot ss) {

        JavaThing[] elements = getElements();

        for (int i = 0; i < elements.length; i++) {

            if (elements[i] == target) {

                return "Element " + i + " of " + this;

            }

        }

        return super.describeReferenceTo(target, ss);

    }

    /*

     * Java object array record (HPROF_GC_OBJ_ARRAY_DUMP)

     * looks as below:

     *

     *     object ID

     *     stack trace serial number (int)

     *     array length (int)

     *     array class ID

     *     array element IDs

     */

    protected final int readValueLength() throws IOException {

        JavaClass cl = getClazz();

        ReadBuffer buf = cl.getReadBuffer();

        int idSize = cl.getIdentifierSize();

        long offset = getOffset() + idSize + 4;

        int len = buf.getInt(offset);

        return len * cl.getIdentifierSize();

    }

    protected final byte[] readValue() throws IOException {

        JavaClass cl = getClazz();

        ReadBuffer buf = cl.getReadBuffer();

        int idSize = cl.getIdentifierSize();

        long offset = getOffset() + idSize + 4;

        int len = buf.getInt(offset);

        if (len == 0) {

            return Snapshot.EMPTY_BYTE_ARRAY;

        } else {

            byte[] res = new byte[len * idSize];

            buf.get(offset + 4 + idSize, res);

            return res;

        }

    }

}