Java example source code file (HttpReader.java)

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Java - Java tags/keywords

allclassesquery, cache\-control, finalizersummaryquery, httpreader, inputstream, instancescountquery, instancesquery, ioexception, net, network, oqlengine, printwriter, rootsquery, snapshot, socket, stringbuilder

The HttpReader.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;

/**
 * Reads a single HTTP query from a socket, and starts up a QueryHandler
 * to server it.
 *
 * @author      Bill Foote
 */


import java.net.Socket;

import java.io.InputStream;
import java.io.BufferedInputStream;
import java.io.IOException;
import java.io.BufferedWriter;
import java.io.PrintWriter;
import java.io.OutputStreamWriter;

import com.sun.tools.hat.internal.model.Snapshot;
import com.sun.tools.hat.internal.oql.OQLEngine;
import com.sun.tools.hat.internal.util.Misc;

public class HttpReader implements Runnable {


    private Socket socket;
    private PrintWriter out;
    private Snapshot snapshot;
    private OQLEngine engine;

    public HttpReader (Socket s, Snapshot snapshot, OQLEngine engine) {
        this.socket = s;
        this.snapshot = snapshot;
        this.engine = engine;
    }

    public void run() {
        InputStream in = null;
        try {
            in = new BufferedInputStream(socket.getInputStream());
            out = new PrintWriter(new BufferedWriter(
                            new OutputStreamWriter(
                                socket.getOutputStream())));
            out.println("HTTP/1.0 200 OK");
            out.println("Cache-Control: no-cache");
            out.println("Pragma: no-cache");
            out.println();
            if (in.read() != 'G' || in.read() != 'E'
                    || in.read() != 'T' || in.read() != ' ') {
                outputError("Protocol error");
            }
            int data;
            StringBuilder queryBuf = new StringBuilder();
            while ((data = in.read()) != -1 && data != ' ') {
                char ch = (char) data;
                queryBuf.append(ch);
            }
            String query = queryBuf.toString();
            query = java.net.URLDecoder.decode(query, "UTF-8");
            QueryHandler handler = null;
            if (snapshot == null) {
                outputError("The heap snapshot is still being read.");
                return;
            } else if (query.equals("/")) {
                handler = new AllClassesQuery(true, engine != null);
                handler.setUrlStart("");
                handler.setQuery("");
            } else if (query.startsWith("/oql/")) {
                if (engine != null) {
                    handler = new OQLQuery(engine);
                    handler.setUrlStart("");
                    handler.setQuery(query.substring(5));
                }
            } else if (query.startsWith("/oqlhelp/")) {
                if (engine != null) {
                    handler = new OQLHelp();
                    handler.setUrlStart("");
                    handler.setQuery("");
                }
            } else if (query.equals("/allClassesWithPlatform/")) {
                handler = new AllClassesQuery(false, engine != null);
                handler.setUrlStart("../");
                handler.setQuery("");
            } else if (query.equals("/showRoots/")) {
                handler = new AllRootsQuery();
                handler.setUrlStart("../");
                handler.setQuery("");
            } else if (query.equals("/showInstanceCounts/includePlatform/")) {
                handler = new InstancesCountQuery(false);
                handler.setUrlStart("../../");
                handler.setQuery("");
            } else if (query.equals("/showInstanceCounts/")) {
                handler = new InstancesCountQuery(true);
                handler.setUrlStart("../");
                handler.setQuery("");
            } else if (query.startsWith("/instances/")) {
                handler = new InstancesQuery(false);
                handler.setUrlStart("../");
                handler.setQuery(query.substring(11));
            }  else if (query.startsWith("/newInstances/")) {
                handler = new InstancesQuery(false, true);
                handler.setUrlStart("../");
                handler.setQuery(query.substring(14));
            }  else if (query.startsWith("/allInstances/")) {
                handler = new InstancesQuery(true);
                handler.setUrlStart("../");
                handler.setQuery(query.substring(14));
            }  else if (query.startsWith("/allNewInstances/")) {
                handler = new InstancesQuery(true, true);
                handler.setUrlStart("../");
                handler.setQuery(query.substring(17));
            } else if (query.startsWith("/object/")) {
                handler = new ObjectQuery();
                handler.setUrlStart("../");
                handler.setQuery(query.substring(8));
            } else if (query.startsWith("/class/")) {
                handler = new ClassQuery();
                handler.setUrlStart("../");
                handler.setQuery(query.substring(7));
            } else if (query.startsWith("/roots/")) {
                handler = new RootsQuery(false);
                handler.setUrlStart("../");
                handler.setQuery(query.substring(7));
            } else if (query.startsWith("/allRoots/")) {
                handler = new RootsQuery(true);
                handler.setUrlStart("../");
                handler.setQuery(query.substring(10));
            } else if (query.startsWith("/reachableFrom/")) {
                handler = new ReachableQuery();
                handler.setUrlStart("../");
                handler.setQuery(query.substring(15));
            } else if (query.startsWith("/rootStack/")) {
                handler = new RootStackQuery();
                handler.setUrlStart("../");
                handler.setQuery(query.substring(11));
            } else if (query.startsWith("/histo/")) {
                handler = new HistogramQuery();
                handler.setUrlStart("../");
                handler.setQuery(query.substring(7));
            } else if (query.startsWith("/refsByType/")) {
                handler = new RefsByTypeQuery();
                handler.setUrlStart("../");
                handler.setQuery(query.substring(12));
            } else if (query.startsWith("/finalizerSummary/")) {
                handler = new FinalizerSummaryQuery();
                handler.setUrlStart("../");
                handler.setQuery("");
            } else if (query.startsWith("/finalizerObjects/")) {
                handler = new FinalizerObjectsQuery();
                handler.setUrlStart("../");
                handler.setQuery("");
            }

            if (handler != null) {
                handler.setOutput(out);
                handler.setSnapshot(snapshot);
                handler.run();
            } else {
                outputError("Query '" + query + "' not implemented");
            }
        } catch (IOException ex) {
            ex.printStackTrace();
        } finally {
            if (out != null) {
                out.close();
            }
            try {
                if (in != null) {
                    in.close();
                }
            } catch (IOException ignored) {
            }
            try {
                socket.close();
            } catch (IOException ignored) {
            }
        }
    }

    private void outputError(String msg) {
        out.println();
        out.println("<html>");
        out.println(Misc.encodeHtml(msg));
        out.println("</body>");
    }

}