1/*
2 * Copyright (c) 2014, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.  Oracle designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Oracle in the LICENSE file that accompanied this code.
10 *
11 * This code is distributed in the hope that it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
14 * version 2 for more details (a copy is included in the LICENSE file that
15 * accompanied this code).
16 *
17 * You should have received a copy of the GNU General Public License version
18 * 2 along with this work; if not, write to the Free Software Foundation,
19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20 *
21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22 * or visit www.oracle.com if you need additional information or have any
23 * questions.
24 */
25package com.sun.beans.introspect;
26
27import java.lang.reflect.Method;
28import java.lang.reflect.Modifier;
29import java.util.Collections;
30import java.util.EventListener;
31import java.util.Iterator;
32import java.util.List;
33import java.util.Map;
34import java.util.TooManyListenersException;
35import java.util.TreeMap;
36
37public final class EventSetInfo {
38    private MethodInfo add;
39    private MethodInfo remove;
40    private MethodInfo get;
41
42    private EventSetInfo() {
43    }
44
45    private boolean initialize() {
46        if ((this.add == null) || (this.remove == null) || (this.remove.type != this.add.type)) {
47            return false;
48        }
49        if ((this.get != null) && (this.get.type != this.add.type)) {
50            this.get = null;
51        }
52        return true;
53    }
54
55    public Class<?> getListenerType() {
56        return this.add.type;
57    }
58
59    public Method getAddMethod() {
60        return this.add.method;
61    }
62
63    public Method getRemoveMethod() {
64        return this.remove.method;
65    }
66
67    public Method getGetMethod() {
68        return (this.get == null) ? null : this.get.method;
69    }
70
71    public boolean isUnicast() {
72        // if the adder method throws the TooManyListenersException
73        // then it is an Unicast event source
74        return this.add.isThrow(TooManyListenersException.class);
75    }
76
77    private static MethodInfo getInfo(MethodInfo info, Method method, int prefix, int postfix) {
78        Class<?> type = (postfix > 0)
79                ? MethodInfo.resolve(method, method.getGenericReturnType()).getComponentType()
80                : MethodInfo.resolve(method, method.getGenericParameterTypes()[0]);
81
82        if ((type != null) && EventListener.class.isAssignableFrom(type)) {
83            String name = method.getName();
84            if (prefix + postfix < name.length()) {
85                if (type.getName().endsWith(name.substring(prefix, name.length() - postfix))) {
86                    if ((info == null) || info.type.isAssignableFrom(type)) {
87                        return new MethodInfo(method, type);
88                    }
89                }
90            }
91        }
92        return info;
93    }
94
95    private static EventSetInfo getInfo(Map<String,EventSetInfo> map, String key) {
96        EventSetInfo info = map.get(key);
97        if (info == null) {
98            info = new EventSetInfo();
99            map.put(key, info);
100        }
101        return info;
102    }
103
104    public static Map<String,EventSetInfo> get(Class<?> type) {
105        List<Method> methods = ClassInfo.get(type).getMethods();
106        if (methods.isEmpty()) {
107            return Collections.emptyMap();
108        }
109        Map<String,EventSetInfo> map = new TreeMap<>();
110        for (Method method : ClassInfo.get(type).getMethods()) {
111            if (!Modifier.isStatic(method.getModifiers())) {
112                Class<?> returnType = method.getReturnType();
113                String name = method.getName();
114                switch (method.getParameterCount()) {
115                    case 1:
116                        if ((returnType == void.class) && name.endsWith("Listener")) {
117                            if (name.startsWith("add")) {
118                                EventSetInfo info = getInfo(map, name.substring(3, name.length() - 8));
119                                info.add = getInfo(info.add, method, 3, 0);
120                            } else if (name.startsWith("remove")) {
121                                EventSetInfo info = getInfo(map, name.substring(6, name.length() - 8));
122                                info.remove = getInfo(info.remove, method, 6, 0);
123                            }
124                        }
125                        break;
126                    case 0:
127                        if (returnType.isArray() && name.startsWith("get") && name.endsWith("Listeners")) {
128                            EventSetInfo info = getInfo(map, name.substring(3, name.length() - 9));
129                            info.get = getInfo(info.get, method, 3, 1);
130                        }
131                        break;
132                }
133            }
134        }
135        Iterator<EventSetInfo> iterator = map.values().iterator();
136        while (iterator.hasNext()) {
137            if (!iterator.next().initialize()) {
138                iterator.remove();
139            }
140        }
141        return !map.isEmpty()
142                ? Collections.unmodifiableMap(map)
143                : Collections.emptyMap();
144    }
145}
146