1 /*
2 * Copyright (c) 2016, 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 */
25
26 package java.lang.invoke;
27
28 import java.util.Map;
29 import jdk.internal.org.objectweb.asm.ClassWriter;
30 import jdk.internal.org.objectweb.asm.Opcodes;
31
32 import java.util.ArrayList;
33 import java.util.HashSet;
34
35 /**
36 * Helper class to assist the GenerateJLIClassesPlugin to get access to
37 * generate classes ahead of time.
38 */
39 class GenerateJLIClassesHelper {
40
41 static byte[] generateBasicFormsClassBytes(String className) {
42 ArrayList<LambdaForm> forms = new ArrayList<>();
43 ArrayList<String> names = new ArrayList<>();
44 HashSet<String> dedupSet = new HashSet<>();
45 for (LambdaForm.BasicType type : LambdaForm.BasicType.values()) {
46 LambdaForm zero = LambdaForm.zeroForm(type);
47 String name = zero.kind.defaultLambdaName
48 + "_" + zero.returnType().basicTypeChar();
49 if (dedupSet.add(name)) {
50 names.add(name);
51 forms.add(zero);
52 }
53
54 LambdaForm identity = LambdaForm.identityForm(type);
55 name = identity.kind.defaultLambdaName
56 + "_" + identity.returnType().basicTypeChar();
57 if (dedupSet.add(name)) {
58 names.add(name);
59 forms.add(identity);
60 }
61 }
62 return generateCodeBytesForLFs(className,
63 names.toArray(new String[0]),
64 forms.toArray(new LambdaForm[0]));
65 }
66
67 static byte[] generateDirectMethodHandleHolderClassBytes(String className,
68 MethodType[] methodTypes, int[] types) {
69 LambdaForm[] forms = new LambdaForm[methodTypes.length];
70 String[] names = new String[methodTypes.length];
71 for (int i = 0; i < forms.length; i++) {
72 forms[i] = DirectMethodHandle.makePreparedLambdaForm(methodTypes[i],
73 types[i]);
74 names[i] = forms[i].kind.defaultLambdaName;
75 }
76 return generateCodeBytesForLFs(className, names, forms);
77 }
78
79 static byte[] generateDelegatingMethodHandleHolderClassBytes(String className,
80 MethodType[] methodTypes) {
81
82 HashSet<MethodType> dedupSet = new HashSet<>();
83 ArrayList<LambdaForm> forms = new ArrayList<>();
84 ArrayList<String> names = new ArrayList<>();
85 for (int i = 0; i < methodTypes.length; i++) {
86 // generate methods representing the DelegatingMethodHandle
87 if (dedupSet.add(methodTypes[i])) {
88 // reinvokers are variant with the associated SpeciesData
89 // and shape of the target LF, but we can easily pregenerate
90 // the basic reinvokers associated with Species_L. Ultimately we
91 // may want to consider pregenerating more of these, which will
92 // require an even more complex naming scheme
93 LambdaForm reinvoker = makeReinvokerFor(methodTypes[i]);
94 forms.add(reinvoker);
95 String speciesSig = BoundMethodHandle
96 .speciesData(reinvoker).fieldSignature();
97 assert(speciesSig.equals("L"));
98 names.add(reinvoker.kind.defaultLambdaName + "_" + speciesSig);
99
100 LambdaForm delegate = makeDelegateFor(methodTypes[i]);
101 forms.add(delegate);
102 names.add(delegate.kind.defaultLambdaName);
103 }
104 }
105 return generateCodeBytesForLFs(className,
106 names.toArray(new String[0]),
107 forms.toArray(new LambdaForm[0]));
108 }
109
110 /*
111 * Generate customized code for a set of LambdaForms of specified types into
112 * a class with a specified name.
113 */
114 private static byte[] generateCodeBytesForLFs(String className,
115 String[] names, LambdaForm[] forms) {
116
117 ClassWriter cw = new ClassWriter(ClassWriter.COMPUTE_MAXS + ClassWriter.COMPUTE_FRAMES);
118 cw.visit(Opcodes.V1_8, Opcodes.ACC_PRIVATE + Opcodes.ACC_FINAL + Opcodes.ACC_SUPER,
119 className, null, InvokerBytecodeGenerator.INVOKER_SUPER_NAME, null);
120 cw.visitSource(className.substring(className.lastIndexOf('/') + 1), null);
121
122 for (int i = 0; i < forms.length; i++) {
123 addMethod(className, names[i], forms[i],
124 forms[i].methodType(), cw);
125 }
126 return cw.toByteArray();
127 }
128
129 private static void addMethod(String className, String methodName, LambdaForm form,
130 MethodType type, ClassWriter cw) {
131 InvokerBytecodeGenerator g
132 = new InvokerBytecodeGenerator(className, methodName, form, type);
133 g.setClassWriter(cw);
134 g.addMethod();
135 }
136
137 private static LambdaForm makeReinvokerFor(MethodType type) {
138 MethodHandle emptyHandle = MethodHandles.empty(type);
139 return DelegatingMethodHandle.makeReinvokerForm(emptyHandle,
140 MethodTypeForm.LF_REBIND,
141 BoundMethodHandle.speciesData_L(),
142 BoundMethodHandle.speciesData_L().getterFunction(0));
143 }
144
145 private static LambdaForm makeDelegateFor(MethodType type) {
146 MethodHandle handle = MethodHandles.empty(type);
147 return DelegatingMethodHandle.makeReinvokerForm(
148 handle,
149 MethodTypeForm.LF_DELEGATE,
150 DelegatingMethodHandle.class,
151 DelegatingMethodHandle.NF_getTarget);
152 }
153
154 static Map.Entry<String, byte[]> generateConcreteBMHClassBytes(
155 final String types) {
156 for (char c : types.toCharArray()) {
157 if ("LIJFD".indexOf(c) < 0) {
158 throw new IllegalArgumentException("All characters must "
159 + "correspond to a basic field type: LIJFD");
160 }
161 }
162 String shortTypes = LambdaForm.shortenSignature(types);
163 final String className =
164 BoundMethodHandle.Factory.speciesInternalClassName(shortTypes);
165 return Map.entry(className,
166 BoundMethodHandle.Factory.generateConcreteBMHClassBytes(
167 shortTypes, types, className));
168 }
169 }