1/*
2 * Copyright (c) 2010, 2013, 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
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8 * particular file as subject to the "Classpath" exception as provided
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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).
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25
26/*
27 * This file is available under and governed by the GNU General Public
28 * License version 2 only, as published by the Free Software Foundation.
29 * However, the following notice accompanied the original version of this
30 * file, and Oracle licenses the original version of this file under the BSD
31 * license:
32 */
33/*
34   Copyright 2009-2013 Attila Szegedi
35
36   Licensed under both the Apache License, Version 2.0 (the "Apache License")
37   and the BSD License (the "BSD License"), with licensee being free to
38   choose either of the two at their discretion.
39
40   You may not use this file except in compliance with either the Apache
41   License or the BSD License.
42
43   If you choose to use this file in compliance with the Apache License, the
44   following notice applies to you:
45
46       You may obtain a copy of the Apache License at
47
48           http://www.apache.org/licenses/LICENSE-2.0
49
50       Unless required by applicable law or agreed to in writing, software
51       distributed under the License is distributed on an "AS IS" BASIS,
52       WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
53       implied. See the License for the specific language governing
54       permissions and limitations under the License.
55
56   If you choose to use this file in compliance with the BSD License, the
57   following notice applies to you:
58
59       Redistribution and use in source and binary forms, with or without
60       modification, are permitted provided that the following conditions are
61       met:
62       * Redistributions of source code must retain the above copyright
63         notice, this list of conditions and the following disclaimer.
64       * Redistributions in binary form must reproduce the above copyright
65         notice, this list of conditions and the following disclaimer in the
66         documentation and/or other materials provided with the distribution.
67       * Neither the name of the copyright holder nor the names of
68         contributors may be used to endorse or promote products derived from
69         this software without specific prior written permission.
70
71       THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
72       IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
73       TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
74       PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL COPYRIGHT HOLDER
75       BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
76       CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
77       SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
78       BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
79       WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
80       OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
81       ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
82*/
83
84package jdk.dynalink.beans;
85
86import java.lang.invoke.MethodHandle;
87import jdk.dynalink.CallSiteDescriptor;
88import jdk.dynalink.linker.LinkerServices;
89
90/**
91 * Represents a single dynamic method. A "dynamic" method can be bound to a single Java method, or can be bound to all
92 * overloaded methods of the same name on a class. Getting an invocation of a dynamic method bound to multiple
93 * overloaded methods will perform overload resolution (actually, it will perform partial overloaded resolution at link
94 * time, but if that fails to identify exactly one target method, it will generate a method handle that will perform the
95 * rest of the overload resolution at invocation time for actual argument types).
96 */
97abstract class DynamicMethod {
98    private final String name;
99
100    DynamicMethod(final String name) {
101        this.name = name;
102    }
103
104    String getName() {
105        return name;
106    }
107
108    /**
109     * Creates an invocation for the dynamic method. If the method is overloaded, it will perform overloaded method
110     * resolution based on the specified method type. The resulting resolution can either identify a single method to be
111     * invoked among the overloads, or it can identify multiple ones. In the latter case, the returned method handle
112     * will perform further overload resolution among these candidates at every invocation. If the method to be invoked
113     * is a variable arguments (vararg) method, it will pack the extra arguments in an array before the invocation of
114     * the underlying method if it is not already done.
115     *
116     * @param callSiteDescriptor the descriptor of the call site
117     * @param linkerServices linker services. Used for language-specific type conversions.
118     * @return an invocation suitable for calling the method from the specified call site.
119     */
120    abstract MethodHandle getInvocation(CallSiteDescriptor callSiteDescriptor, LinkerServices linkerServices);
121
122    /**
123     * Returns a single dynamic method representing a single underlying Java method (possibly selected among several
124     * overloads) with formal parameter types exactly matching the passed signature.
125     * @param paramTypes the comma-separated list of requested parameter type names. The names will match both
126     * qualified and unqualified type names.
127     * @return a single dynamic method representing a single underlying Java method, or null if none of the Java methods
128     * behind this dynamic method exactly match the requested parameter types.
129     */
130    abstract SingleDynamicMethod getMethodForExactParamTypes(String paramTypes);
131
132    /**
133     * True if this dynamic method already contains a method with an identical signature as the passed in method.
134     * @param method the method to check
135     * @return true if it already contains an equivalent method.
136     */
137    abstract boolean contains(SingleDynamicMethod method);
138
139    static String getClassAndMethodName(final Class<?> clazz, final String name) {
140        final String clazzName = clazz.getCanonicalName();
141        return (clazzName == null ? clazz.getName() : clazzName) + "." + name;
142    }
143
144    @Override
145    public String toString() {
146        return "[" + getClass().getName() + " " + getName() + "]";
147    }
148
149    /**
150     * True if this method happens to be a constructor method.
151     *
152     * @return true if this represents a constructor.
153     */
154    boolean isConstructor() {
155        return false;
156    }
157}
158