1 /*
2 * Copyright (c) 2002, 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 com.sun.tools.javac.jvm;
27
28 import java.util.*;
29
30 import com.sun.tools.javac.code.Flags;
31 import com.sun.tools.javac.code.Symbol;
32 import com.sun.tools.javac.util.*;
33
34 import static com.sun.tools.javac.main.Option.TARGET;
35
36 /** The classfile version target.
37 *
38 * <p><b>This is NOT part of any supported API.
39 * If you write code that depends on this, you do so at your own risk.
40 * This code and its internal interfaces are subject to change or
41 * deletion without notice.</b>
42 */
43 public enum Target {
44 JDK1_1("1.1", 45, 3),
45 JDK1_2("1.2", 46, 0),
46 JDK1_3("1.3", 47, 0),
47
48 /** J2SE1.4 = Merlin. */
49 JDK1_4("1.4", 48, 0),
50
51 /** JDK 5, codename Tiger. */
52 JDK1_5("1.5", 49, 0),
53
54 /** JDK 6. */
55 JDK1_6("1.6", 50, 0),
56
57 /** JDK 7. */
58 JDK1_7("1.7", 51, 0),
59
60 /** JDK 8. */
61 JDK1_8("1.8", 52, 0),
62
63 /** JDK 9. */
64 JDK1_9("1.9", 53, 0);
65
66 private static final Context.Key<Target> targetKey = new Context.Key<>();
67
68 public static Target instance(Context context) {
69 Target instance = context.get(targetKey);
70 if (instance == null) {
71 Options options = Options.instance(context);
72 String targetString = options.get(TARGET);
73 if (targetString != null) instance = lookup(targetString);
74 if (instance == null) instance = DEFAULT;
75 context.put(targetKey, instance);
76 }
77 return instance;
78 }
79
80 public static final Target MIN = Target.JDK1_6;
81
82 private static final Target MAX = values()[values().length - 1];
83
84 private static final Map<String,Target> tab = new HashMap<>();
85 static {
86 for (Target t : values()) {
87 tab.put(t.name, t);
88 }
89 tab.put("5", JDK1_5);
90 tab.put("6", JDK1_6);
91 tab.put("7", JDK1_7);
92 tab.put("8", JDK1_8);
93 tab.put("9", JDK1_9);
94 }
95
96 public final String name;
97 public final int majorVersion;
98 public final int minorVersion;
99 private Target(String name, int majorVersion, int minorVersion) {
100 this.name = name;
101 this.majorVersion = majorVersion;
102 this.minorVersion = minorVersion;
103 }
104
105 public static final Target DEFAULT = JDK1_9;
106
107 public static Target lookup(String name) {
108 return tab.get(name);
109 }
110
111 /** Return the character to be used in constructing synthetic
112 * identifiers, where not specified by the JLS.
113 */
114 public char syntheticNameChar() {
115 return '$';
116 }
117
118 /** Does the VM support an invokedynamic instruction?
119 */
120 public boolean hasInvokedynamic() {
121 return compareTo(JDK1_7) >= 0;
122 }
123
124 /** Does the target JDK contains the java.util.Objects class?
125 */
126 public boolean hasObjects() {
127 return compareTo(JDK1_7) >= 0;
128 }
129
130 /** Does the VM support polymorphic method handle invocation?
131 * Affects the linkage information output to the classfile.
132 * An alias for {@code hasInvokedynamic}, since all the JSR 292 features appear together.
133 */
134 public boolean hasMethodHandles() {
135 return hasInvokedynamic();
136 }
137
138 /** Does the target JDK contain StringConcatFactory class?
139 */
140 public boolean hasStringConcatFactory() {
141 return compareTo(JDK1_9) >= 0;
142 }
143
144 /** Value of platform release used to access multi-release jar files
145 */
146 public String multiReleaseValue() {
147 return Integer.toString(this.ordinal() - Target.JDK1_1.ordinal() + 1);
148 }
149
150 }