OptionLister.java

/*
 * Copyright 2004 Sun Microsystems, Inc.  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.  Sun designates this
 * particular file as subject to the "Classpath" exception as provided
 * by Sun 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
 * CA 95054 USA or visit www.sun.com if you need additional information or
 * have any questions.
 */

package sun.tools.jstat;

import java.util.*;
import java.net.*;
import java.io.*;

/**
 * A class for listing the available options in the jstat_options file.
 *
 * @author Brian Doherty
 * @since 1.5
 */
public class OptionLister {
    private static final boolean debug = false;
    private URL[] sources;

    public OptionLister(URL[] sources) {
        this.sources = sources;
    }

    public void print(PrintStream ps) {
        Comparator<OptionFormat> c = new Comparator<OptionFormat>() {
               public int compare(OptionFormat o1, OptionFormat o2) {
                   OptionFormat of1 = o1;
                   OptionFormat of2 = o2;
                   return (of1.getName().compareTo(of2.getName()));
               }
        };

        Set<OptionFormat> options = new TreeSet<OptionFormat>(c);

        for (int i = 0; i < sources.length; i++) {
            try {
                URL u = sources[i];
                Reader r = new BufferedReader(
                        new InputStreamReader(u.openStream()));
                Set<OptionFormat> s = new Parser(r).parseOptions();
                options.addAll(s);
            } catch (IOException e) {
                if (debug) {
                    System.err.println(e.getMessage());
                    e.printStackTrace();
                }
            } catch (ParserException e) {
                // Exception in parsing the options file.
                System.err.println(sources[i] + ": " + e.getMessage());
                System.err.println("Parsing of " + sources[i] + " aborted");
            }
        }

        for ( OptionFormat of : options) {
            if (of.getName().compareTo("timestamp") == 0) {
              // ignore the special timestamp OptionFormat.
              continue;
            }
            ps.println("-" + of.getName());
        }
    }
}