001/*
002 * Licensed to the Apache Software Foundation (ASF) under one
003 * or more contributor license agreements.  See the NOTICE file
004 * distributed with this work for additional information
005 * regarding copyright ownership.  The ASF licenses this file
006 * to you under the Apache License, Version 2.0 (the
007 * "License"); you may not use this file except in compliance
008 * with the License.  You may obtain a copy of the License at
009 *
010 *   https://www.apache.org/licenses/LICENSE-2.0
011 *
012 * Unless required by applicable law or agreed to in writing,
013 * software distributed under the License is distributed on an
014 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
015 * KIND, either express or implied.  See the License for the
016 * specific language governing permissions and limitations
017 * under the License.
018 */
019package org.apache.bcel.verifier;
020
021import java.util.ArrayList;
022import java.util.List;
023import java.util.Set;
024import java.util.TreeSet;
025
026import javax.swing.ListModel;
027import javax.swing.event.ListDataEvent;
028import javax.swing.event.ListDataListener;
029
030import org.apache.commons.lang3.ArrayUtils;
031
032/**
033 * This class implements an adapter; it implements both a Swing ListModel and a VerifierFactoryObserver.
034 */
035public class VerifierFactoryListModel implements VerifierFactoryObserver, ListModel<String> {
036
037    private final List<ListDataListener> listeners = new ArrayList<>();
038    private final Set<String> cache = new TreeSet<>();
039
040    /**
041     * Constructs a VerifierFactoryListModel.
042     */
043    public VerifierFactoryListModel() {
044        VerifierFactory.attach(this);
045        update(null); // fill cache.
046    }
047
048    @Override
049    public synchronized void addListDataListener(final ListDataListener l) {
050        listeners.add(l);
051    }
052
053    @Override
054    public synchronized String getElementAt(final int index) {
055        return cache.toArray(ArrayUtils.EMPTY_STRING_ARRAY)[index];
056    }
057
058    @Override
059    public synchronized int getSize() {
060        return cache.size();
061    }
062
063    @Override
064    public synchronized void removeListDataListener(final ListDataListener l) {
065        listeners.remove(l);
066    }
067
068    @Override
069    public synchronized void update(final String s) {
070        final Verifier[] verifiers = VerifierFactory.getVerifiers();
071        final int verifierLen = verifiers.length;
072        cache.clear();
073        for (final Verifier verifier : verifiers) {
074            cache.add(verifier.getClassName());
075        }
076        for (final ListDataListener listener : listeners) {
077            listener.contentsChanged(new ListDataEvent(this, ListDataEvent.CONTENTS_CHANGED, 0, verifierLen - 1));
078        }
079    }
080
081}