Java example source code file (ClassQuery.java)

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Java - Java tags/keywords

classquery, comparer, data, enumeration, exclude, include, javaclass, javafield, javaheapobject, javastatic, members\:, queries, queryhandler, reference, util

The ClassQuery.java Java example source code

/*
 * Copyright (c) 1997, 2013, 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 com.sun.tools.hat.internal.model.*;
import com.sun.tools.hat.internal.util.ArraySorter;
import com.sun.tools.hat.internal.util.Comparer;

import java.util.Enumeration;

/**
 *
 * @author      Bill Foote
 */


class ClassQuery extends QueryHandler {


    public ClassQuery() {
    }

    public void run() {
        startHtml("Class " + query);
        JavaClass clazz = snapshot.findClass(query);
        if (clazz == null) {
            error("class not found: " + query);
        } else {
            printFullClass(clazz);
        }
        endHtml();
    }

    protected void printFullClass(JavaClass clazz) {
        out.print("<h1>");
        print(clazz.toString());
        out.println("</h1>");

        out.println("<h2>Superclass:");
        printClass(clazz.getSuperclass());

        out.println("<h2>Loader Details");
        out.println("<h3>ClassLoader:");
        printThing(clazz.getLoader());

        out.println("<h3>Signers:");
        printThing(clazz.getSigners());

        out.println("<h3>Protection Domain:");
        printThing(clazz.getProtectionDomain());

        out.println("<h2>Subclasses:");
        JavaClass[] sc = clazz.getSubclasses();
        for (int i = 0; i < sc.length; i++) {
            out.print("    ");
            printClass(sc[i]);
            out.println("<br>");
        }

        out.println("<h2>Instance Data Members:");
        JavaField[] ff = clazz.getFields().clone();
        ArraySorter.sort(ff, new Comparer() {
            public int compare(Object lhs, Object rhs) {
                JavaField left = (JavaField) lhs;
                JavaField right = (JavaField) rhs;
                return left.getName().compareTo(right.getName());
            }
        });
        for (int i = 0; i < ff.length; i++) {
            out.print("    ");
            printField(ff[i]);
            out.println("<br>");
        }

        out.println("<h2>Static Data Members:");
        JavaStatic[] ss = clazz.getStatics();
        for (int i = 0; i < ss.length; i++) {
            printStatic(ss[i]);
            out.println("<br>");
        }

        out.println("<h2>Instances");

        printAnchorStart();
        print("instances/" + encodeForURL(clazz));
        out.print("\">");
        out.println("Exclude subclasses</a>
");

        printAnchorStart();
        print("allInstances/" + encodeForURL(clazz));
        out.print("\">");
        out.println("Include subclasses</a>
");


        if (snapshot.getHasNewSet()) {
            out.println("<h2>New Instances");

            printAnchorStart();
            print("newInstances/" + encodeForURL(clazz));
            out.print("\">");
            out.println("Exclude subclasses</a>
");

            printAnchorStart();
            print("allNewInstances/" + encodeForURL(clazz));
            out.print("\">");
            out.println("Include subclasses</a>
");
        }

        out.println("<h2>References summary by Type");
        printAnchorStart();
        print("refsByType/" + encodeForURL(clazz));
        out.print("\">");
        out.println("References summary by type</a>");

        printReferencesTo(clazz);
    }

    protected void printReferencesTo(JavaHeapObject obj) {
        if (obj.getId() == -1) {
            return;
        }
        out.println("<h2>References to this object:");
        out.flush();
        Enumeration referers = obj.getReferers();
        while (referers.hasMoreElements()) {
            JavaHeapObject ref = (JavaHeapObject) referers.nextElement();
            printThing(ref);
            print (" : " + ref.describeReferenceTo(obj, snapshot));
            // If there are more than one references, this only gets the
            // first one.
            out.println("<br>");
        }

        out.println("<h2>Other Queries");
        out.println("Reference Chains from Rootset");
        long id = obj.getId();

        out.print("<ul>
");
        printAnchorStart();
        out.print("roots/");
        printHex(id);
        out.print("\">");
        out.println("Exclude weak refs</a>");

        out.print("<li>");
        printAnchorStart();
        out.print("allRoots/");
        printHex(id);
        out.print("\">");
        out.println("Include weak refs</a>");

        printAnchorStart();
        out.print("reachableFrom/");
        printHex(id);
        out.print("\">");
        out.println("Objects reachable from here</a>
");
    }


}