1 /* 2 * Copyright (c) 2002, 2017, 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 /** JDK 10, initially an alias for 9 */ 67 JDK1_10("1.10", 53, 0); 68 69 private static final Context.Key<Target> targetKey = new Context.Key<>(); 70 71 public static Target instance(Context context) { 72 Target instance = context.get(targetKey); 73 if (instance == null) { 74 Options options = Options.instance(context); 75 String targetString = options.get(TARGET); 76 if (targetString != null) instance = lookup(targetString); 77 if (instance == null) instance = DEFAULT; 78 context.put(targetKey, instance); 79 } 80 return instance; 81 } 82 83 public static final Target MIN = Target.JDK1_6; 84 85 private static final Target MAX = values()[values().length - 1]; 86 87 private static final Map<String,Target> tab = new HashMap<>(); 88 static { 89 for (Target t : values()) { 90 tab.put(t.name, t); 91 } 92 tab.put("5", JDK1_5); 93 tab.put("6", JDK1_6); 94 tab.put("7", JDK1_7); 95 tab.put("8", JDK1_8); 96 tab.put("9", JDK1_9); 97 tab.put("10", JDK1_10); 98 } 99 100 public final String name; 101 public final int majorVersion; 102 public final int minorVersion; 103 private Target(String name, int majorVersion, int minorVersion) { 104 this.name = name; 105 this.majorVersion = majorVersion; 106 this.minorVersion = minorVersion; 107 } 108 109 public static final Target DEFAULT = values()[values().length - 1]; 110 111 public static Target lookup(String name) { 112 return tab.get(name); 113 } 114 115 /** Return the character to be used in constructing synthetic 116 * identifiers, where not specified by the JLS. 117 */ 118 public char syntheticNameChar() { 119 return '$'; 120 } 121 122 /** Does the VM support an invokedynamic instruction? 123 */ 124 public boolean hasInvokedynamic() { 125 return compareTo(JDK1_7) >= 0; 126 } 127 128 /** Does the target JDK contains the java.util.Objects class? 129 */ 130 public boolean hasObjects() { 131 return compareTo(JDK1_7) >= 0; 132 } 133 134 /** Does the VM support polymorphic method handle invocation? 135 * Affects the linkage information output to the classfile. 136 * An alias for {@code hasInvokedynamic}, since all the JSR 292 features appear together. 137 */ 138 public boolean hasMethodHandles() { 139 return hasInvokedynamic(); 140 } 141 142 /** Does the target JDK contain StringConcatFactory class? 143 */ 144 public boolean hasStringConcatFactory() { 145 return compareTo(JDK1_9) >= 0; 146 } 147 148 /** Value of platform release used to access multi-release jar files 149 */ 150 public String multiReleaseValue() { 151 return Integer.toString(this.ordinal() - Target.JDK1_1.ordinal() + 1); 152 } 153 154 /** Does the target VM support nestmate access? 155 */ 156 public boolean hasNestmateAccess() { 157 return compareTo(JDK1_10) >= 0; 158 } 159 160 /** Does the target VM support virtual private invocations? 161 */ 162 public boolean hasVirtualPrivateInvoke() { 163 return compareTo(JDK1_10) >= 0; 164 } 165 166 }