Java example source code file (ObjectQuery.java)

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Java - Java tags/keywords

classquery, comparer, integer, javaclass, javafield, javaheapobject, javaobject, javaobjectarray, javathing, javavaluearray, object, objectquery, stacktrace, util

The ObjectQuery.java Java example source code

/*
 * 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.server;

import  java.util.Enumeration;

import com.sun.tools.hat.internal.model.*;
import com.sun.tools.hat.internal.util.ArraySorter;
import com.sun.tools.hat.internal.util.Comparer;

/**
 *
 * @author      Bill Foote
 */


class ObjectQuery extends ClassQuery {
        // We inherit printFullClass from ClassQuery

    public ObjectQuery() {
    }

    public void run() {
        startHtml("Object at " + query);
        long id = parseHex(query);
        JavaHeapObject thing = snapshot.findThing(id);
        //
        // In the following, I suppose we really should use a visitor
        // pattern.  I'm not that strongly motivated to do this, however:
        // This is the only typecase there is, and the default for an
        // unrecognized type is to do something reasonable.
        //
        if (thing == null) {
            error("object not found");
        } else if (thing instanceof JavaClass) {
            printFullClass((JavaClass) thing);
        } else if (thing instanceof JavaValueArray) {
            print(((JavaValueArray) thing).valueString(true));
            printAllocationSite(thing);
            printReferencesTo(thing);
        } else if (thing instanceof JavaObjectArray) {
            printFullObjectArray((JavaObjectArray) thing);
            printAllocationSite(thing);
            printReferencesTo(thing);
        } else if (thing instanceof JavaObject) {
            printFullObject((JavaObject) thing);
            printAllocationSite(thing);
            printReferencesTo(thing);
        } else {
            // We should never get here
            print(thing.toString());
            printReferencesTo(thing);
        }
        endHtml();
    }


    private void printFullObject(JavaObject obj) {
        out.print("<h1>instance of ");
        print(obj.toString());
        out.print(" <small>(" + obj.getSize() + " bytes)");
        out.println("</h1>\n");

        out.println("<h2>Class:");
        printClass(obj.getClazz());

        out.println("<h2>Instance data members:");
        final JavaThing[] things = obj.getFields();
        final JavaField[] fields = obj.getClazz().getFieldsForInstance();
        Integer[] hack = new Integer[things.length];
        for (int i = 0; i < things.length; i++) {
            hack[i] = new Integer(i);
        }
        ArraySorter.sort(hack, new Comparer() {
            public int compare(Object lhs, Object rhs) {
                JavaField left = fields[((Integer) lhs).intValue()];
                JavaField right = fields[((Integer) rhs).intValue()];
                return left.getName().compareTo(right.getName());
            }
        });
        for (int i = 0; i < things.length; i++) {
            int index = hack[i].intValue();
            printField(fields[index]);
            out.print(" : ");
            printThing(things[index]);
            out.println("<br>");
        }
    }

    private void printFullObjectArray(JavaObjectArray arr) {
        JavaThing[] elements = arr.getElements();
        out.println("<h1>Array of " + elements.length + " objects");

        out.println("<h2>Class:");
        printClass(arr.getClazz());

        out.println("<h2>Values");
        for (int i = 0; i < elements.length; i++) {
            out.print("" + i + " : ");
            printThing(elements[i]);
            out.println("<br>");
        }
    }

    //
    // Print the StackTrace where this was allocated
    //
    private void printAllocationSite(JavaHeapObject obj) {
        StackTrace trace = obj.getAllocatedFrom();
        if (trace == null || trace.getFrames().length == 0) {
            return;
        }
        out.println("<h2>Object allocated from:");
        printStackTrace(trace);
    }
}