1/* 2 * Copyright (c) 2015, 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. 8 * 9 * This code is distributed in the hope that it will be useful, but WITHOUT 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 12 * version 2 for more details (a copy is included in the LICENSE file that 13 * accompanied this code). 14 * 15 * You should have received a copy of the GNU General Public License version 16 * 2 along with this work; if not, write to the Free Software Foundation, 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 18 * 19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 20 * or visit www.oracle.com if you need additional information or have any 21 * questions. 22 */ 23 24import javax.tools.JavaCompiler; 25import javax.tools.StandardJavaFileManager; 26import javax.tools.StandardLocation; 27import javax.tools.ToolProvider; 28import java.io.IOException; 29import java.nio.file.Files; 30import java.nio.file.Path; 31import java.util.Arrays; 32import java.util.Collections; 33import java.util.List; 34import java.util.stream.Collectors; 35 36/** 37 * This class consists exclusively of static utility methods for invoking the 38 * java compiler. 39 */ 40 41public final class CompilerUtils { 42 private CompilerUtils() { } 43 44 /** 45 * Compile all the java sources in {@code <source>/**} to 46 * {@code <destination>/**}. The destination directory will be created if 47 * it doesn't exist. 48 * 49 * All warnings/errors emitted by the compiler are output to System.out/err. 50 * 51 * @return true if the compilation is successful 52 * 53 * @throws IOException 54 * if there is an I/O error scanning the source tree or 55 * creating the destination directory 56 * @throws UnsupportedOperationException 57 * if there is no system java compiler 58 */ 59 public static boolean compile(Path source, Path destination, String ... options) 60 throws IOException 61 { 62 JavaCompiler compiler = ToolProvider.getSystemJavaCompiler(); 63 if (compiler == null) { 64 // no compiler available 65 throw new UnsupportedOperationException("Unable to get system java compiler. " + 66 "Perhaps, jdk.compiler module is not available."); 67 } 68 StandardJavaFileManager jfm = compiler.getStandardFileManager(null, null, null); 69 70 List<Path> sources 71 = Files.find(source, Integer.MAX_VALUE, 72 (file, attrs) -> (file.toString().endsWith(".java"))) 73 .collect(Collectors.toList()); 74 75 Files.createDirectories(destination); 76 jfm.setLocation(StandardLocation.CLASS_PATH, Collections.EMPTY_LIST); 77 jfm.setLocationFromPaths(StandardLocation.CLASS_OUTPUT, 78 Arrays.asList(destination)); 79 80 List<String> opts = Arrays.asList(options); 81 JavaCompiler.CompilationTask task 82 = compiler.getTask(null, jfm, null, opts, null, 83 jfm.getJavaFileObjectsFromPaths(sources)); 84 85 return task.call(); 86 } 87} 88