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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

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 * 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.

 *

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 */

/*

 *  @test

 *  @bug 6822627

 *  @summary Test that ReferenceType.constantPool does not produce an NPE

 *

 *  @author Egor Ushakov

 *

 *  @modules jdk.jdi/com.sun.tools.jdi

 *  @run build TestScaffold VMConnection

 *  @run compile -g ConstantPoolInfoGC.java

 *  @run main/othervm ConstantPoolInfoGC

 */

import com.sun.jdi.ReferenceType;

import com.sun.tools.jdi.ReferenceTypeImpl;

import java.lang.ref.Reference;

import java.lang.reflect.Field;

import java.util.Arrays;

    /********** target program **********/

class ConstantPoolGCTarg {

    public static void main(String[] args){

        System.out.println("Anything");

    }

}

    /********** test program **********/

public class ConstantPoolInfoGC extends TestScaffold {

    ReferenceType targetClass;

    ConstantPoolInfoGC(String args[]) {

        super(args);

    }

    public static void main(String[] args)      throws Exception {

        new ConstantPoolInfoGC(args).startTests();

    }

    /********** test core **********/

    protected void runTests() throws Exception {

        targetClass = startToMain("ConstantPoolGCTarg").location().declaringType();

        if (vm().canGetConstantPool()) {

            byte[] cpbytes = targetClass.constantPool();

            // imitate SoftReference cleared

            Field constantPoolBytesRef = ReferenceTypeImpl.class.getDeclaredField("constantPoolBytesRef");

            constantPoolBytesRef.setAccessible(true);

            Reference softRef = (Reference) constantPoolBytesRef.get(targetClass);

            softRef.clear();

            byte[] cpbytes2 = targetClass.constantPool();

            if (!Arrays.equals(cpbytes, cpbytes2)) {

                failure("Consequent constantPool results vary, first was : " + cpbytes + ", now: " + cpbytes2);

            };

        } else {

            System.out.println("can get constant pool version not supported");

        }

        /*

         * resume until end

         */

        listenUntilVMDisconnect();

        /*

         * deal with results of test

         * if anything has called failure("foo") testFailed will be true

         */

        if (!testFailed) {

            println("ConstantPoolInfoGC: passed");

        } else {

            throw new Exception("ConstantPoolInfoGC: failed");

        }

    }

}