LinkRequest.java revision 1551:f3b883bec2d0
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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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 *
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19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
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21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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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.linker;
85
86import jdk.dynalink.CallSiteDescriptor;
87import jdk.dynalink.DynamicLinker;
88import jdk.dynalink.DynamicLinkerFactory;
89
90/**
91 * Represents a request to link a particular invocation at a particular call
92 * site. Instances of these requests will be constructed and passed to all
93 * {@link GuardingDynamicLinker} objects managed by the {@link DynamicLinker}
94 * that is trying to link the call site.
95 */
96public interface LinkRequest {
97    /**
98     * Returns the call site descriptor for the call site being linked.
99     *
100     * @return the call site descriptor for the call site being linked.
101     */
102    public CallSiteDescriptor getCallSiteDescriptor();
103
104    /**
105     * Returns the arguments for the invocation being linked. The returned array
106     * must be a clone; modifications to it must not affect the arguments in
107     * this request.
108     *
109     * @return the arguments for the invocation being linked.
110     */
111    public Object[] getArguments();
112
113    /**
114     * Returns the first argument for the invocation being linked; this is
115     * typically the receiver object. This is a shorthand for
116     * {@code getArguments()[0]} that also avoids the cloning of the arguments
117     * array.
118     *
119     * @return the receiver object.
120     */
121    public Object getReceiver();
122
123    /**
124     * Returns true if the call site is considered unstable, that is, it has been relinked more times than was
125     * specified in {@link DynamicLinkerFactory#setUnstableRelinkThreshold(int)}. Linkers should use this as a
126     * hint to prefer producing linkage that is more stable (its guard fails less frequently), even if that assumption
127     * causes a less effective version of an operation to be linked. This is just a hint, though, and linkers are
128     * allowed to ignore this property.
129     * @return true if the call site is considered unstable.
130     */
131    public boolean isCallSiteUnstable();
132
133    /**
134     * Returns a request identical to this one with call site descriptor and arguments replaced with the ones specified.
135     *
136     * @param callSiteDescriptor the new call site descriptor
137     * @param arguments the new arguments
138     * @return a new request identical to this one, except with the call site descriptor and arguments replaced with the
139     * specified ones.
140     */
141    public LinkRequest replaceArguments(CallSiteDescriptor callSiteDescriptor, Object... arguments);
142}
143