1 /* 2 * Copyright (c) 2014, 2018, 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 package gc.g1.unloading.bytecode; 24 25 import java.util.HashMap; 26 import java.util.Map; 27 import java.util.Random; 28 29 import vm.share.InMemoryJavaCompiler; 30 31 /** 32 * BytecodeFactory that employs in memory compilation. 33 */ 34 public class BytecodeGeneratorFactory implements BytecodeFactory { 35 36 private Random random; 37 38 private SourceGenerator sourceGenerator; 39 BytecodeGeneratorFactory(long seed)40 public BytecodeGeneratorFactory(long seed) { 41 random = new Random(seed); 42 sourceGenerator = new SourceGenerator(random.nextLong()); 43 } 44 45 @Override createBytecode(String className)46 public Bytecode createBytecode(String className) { 47 Map<String, CharSequence> sources = new HashMap<String, CharSequence>(); 48 sources.put(className, sourceGenerator.generateSource(className, 49 "public static void main() { System.out.println(\"From main method in in-mem-compiled code " + random.nextGaussian() + 50 " + str_bytesToReplace0 str_bytesToReplace1\"); }\n " + 51 "public static int methodForCompilation(Object object) { int i = object.hashCode(); i = i * 2000 / 1994 + 153; return i; }\n")); 52 byte[] bytecode = InMemoryJavaCompiler.compile(sources).values().iterator().next(); 53 return new Bytecode(className, bytecode); 54 } 55 56 } 57