| /* |
| * Copyright (c) 1998, 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. |
| */ |
| |
| /* @test |
| @bug 4098742 |
| @summary Test biginteger modpow method |
| @author Michael McCloskey |
| @run main/othervm ModPowPowersof2 |
| */ |
| |
| import java.math.BigInteger; |
| import java.io.BufferedReader; |
| import java.io.InputStreamReader; |
| import java.io.File; |
| import java.io.IOException; |
| |
| /** |
| * This class tests to see if using modPow on a power |
| * of two crashes the vm |
| * |
| */ |
| public class ModPowPowersof2 { |
| |
| public static void main(String args[]) throws Exception { |
| // Construct a command that runs the test in other vm |
| String[] command = new String[4]; |
| int n = 0; |
| |
| command[n++] = System.getProperty("java.home") + File.separator + |
| "bin" + File.separator + "java"; |
| if (System.getProperty("java.class.path") != null) { |
| command[n++] = "-classpath"; |
| command[n++] = System.getProperty("java.class.path"); |
| } |
| |
| command[n++] = "ModPowPowersof2$ModTester"; |
| |
| // Exec another vm to run test in |
| Process p = null; |
| p = Runtime.getRuntime().exec(command); |
| |
| // Read the result to determine if test failed |
| BufferedReader in = new BufferedReader(new InputStreamReader( |
| p.getInputStream())); |
| String s; |
| s = in.readLine(); |
| if (s == null) |
| throw new RuntimeException("ModPow causes vm crash"); |
| |
| } |
| |
| public static class ModTester { |
| public static void main(String [] args) { |
| BigInteger two = BigInteger.valueOf(2); |
| BigInteger four = BigInteger.valueOf(4); |
| |
| two.modPow(two, BigInteger.valueOf(4)); |
| two.modPow(two, BigInteger.valueOf(8)); |
| two.modPow(four, BigInteger.valueOf(8)); |
| |
| System.out.println("success"); |
| } |
| } |
| |
| } |