1 /* 2 * Copyright 2021 Google Inc. All Rights Reserved. 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 package com.google.turbine.options; 18 19 import com.google.auto.value.AutoValue; 20 import com.google.common.collect.ImmutableList; 21 import com.google.common.primitives.Ints; 22 import java.util.Iterator; 23 import java.util.OptionalInt; 24 import javax.lang.model.SourceVersion; 25 26 /** 27 * The language version being compiled, corresponding to javac's {@code -source}, {@code -target}, 28 * and {@code --release} flags. 29 */ 30 @AutoValue 31 public abstract class LanguageVersion { 32 33 /** The source version. */ source()34 public abstract int source(); 35 36 /** The target version. */ target()37 public abstract int target(); 38 39 /** 40 * The release version. 41 * 42 * <p>If set, system APIs will be resolved from the host JDK's ct.sym instead of using the 43 * provided {@code --bootclasspath}. 44 */ release()45 public abstract OptionalInt release(); 46 47 /** The class file major version corresponding to the {@link #target}. */ majorVersion()48 public int majorVersion() { 49 return target() + 44; 50 } 51 sourceVersion()52 public SourceVersion sourceVersion() { 53 try { 54 return SourceVersion.valueOf("RELEASE_" + source()); 55 } catch (IllegalArgumentException unused) { 56 return SourceVersion.latestSupported(); 57 } 58 } 59 create(int source, int target, OptionalInt release)60 private static LanguageVersion create(int source, int target, OptionalInt release) { 61 return new AutoValue_LanguageVersion(source, target, release); 62 } 63 64 /** The default language version. Currently Java 8. */ createDefault()65 public static LanguageVersion createDefault() { 66 return create(DEFAULT, DEFAULT, OptionalInt.empty()); 67 } 68 69 private static final int DEFAULT = 8; 70 71 /** Returns the effective {@code LanguageVersion} for the given list of javac options. */ fromJavacopts(ImmutableList<String> javacopts)72 public static LanguageVersion fromJavacopts(ImmutableList<String> javacopts) { 73 int sourceVersion = DEFAULT; 74 int targetVersion = DEFAULT; 75 OptionalInt release = OptionalInt.empty(); 76 Iterator<String> it = javacopts.iterator(); 77 while (it.hasNext()) { 78 String option = it.next(); 79 switch (option) { 80 case "-source": 81 case "--source": 82 if (!it.hasNext()) { 83 throw new IllegalArgumentException(option + " requires an argument"); 84 } 85 sourceVersion = parseVersion(it.next()); 86 release = OptionalInt.empty(); 87 break; 88 case "-target": 89 case "--target": 90 if (!it.hasNext()) { 91 throw new IllegalArgumentException(option + " requires an argument"); 92 } 93 targetVersion = parseVersion(it.next()); 94 release = OptionalInt.empty(); 95 break; 96 case "--release": 97 if (!it.hasNext()) { 98 throw new IllegalArgumentException(option + " requires an argument"); 99 } 100 String value = it.next(); 101 Integer n = Ints.tryParse(value); 102 if (n == null) { 103 throw new IllegalArgumentException("invalid --release version: " + value); 104 } 105 release = OptionalInt.of(n); 106 sourceVersion = n; 107 targetVersion = n; 108 break; 109 default: 110 break; 111 } 112 } 113 return create(sourceVersion, targetVersion, release); 114 } 115 parseVersion(String value)116 private static int parseVersion(String value) { 117 boolean hasPrefix = value.startsWith("1."); 118 Integer version = Ints.tryParse(hasPrefix ? value.substring("1.".length()) : value); 119 if (version == null || !isValidVersion(version, hasPrefix)) { 120 throw new IllegalArgumentException("invalid -source version: " + value); 121 } 122 return version; 123 } 124 isValidVersion(int version, boolean hasPrefix)125 private static boolean isValidVersion(int version, boolean hasPrefix) { 126 if (version < 5) { 127 // the earliest source version supported by JDK 8 is Java 5 128 return false; 129 } 130 if (hasPrefix && version > 10) { 131 // javac supports legacy `1.*` version numbers for source versions up to Java 10 132 return false; 133 } 134 return true; 135 } 136 } 137