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/*
* Copyright (c) 2014, 2018, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
* or visit www.oracle.com if you need additional information or have any
* questions.
*/
package gc.g1.unloading.bytecode;
import java.util.HashMap;
import java.util.Map;
import java.util.Random;
import vm.share.InMemoryJavaCompiler;
/**
* BytecodeFactory that employs in memory compilation.
*/
public class BytecodeGeneratorFactory implements BytecodeFactory {
private Random random;
private SourceGenerator sourceGenerator;
public BytecodeGeneratorFactory(long seed) {
random = new Random(seed);
sourceGenerator = new SourceGenerator(random.nextLong());
}
@Override
public Bytecode createBytecode(String className) {
Map<String, CharSequence> sources = new HashMap<String, CharSequence>();
sources.put(className, sourceGenerator.generateSource(className,
"public static void main() { System.out.println(\"From main method in in-mem-compiled code " + random.nextGaussian() +
" + str_bytesToReplace0 str_bytesToReplace1\"); }\n " +
"public static int methodForCompilation(Object object) { int i = object.hashCode(); i = i * 2000 / 1994 + 153; return i; }\n"));
byte[] bytecode = InMemoryJavaCompiler.compile(sources).values().iterator().next();
return new Bytecode(className, bytecode);
}
}
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