Java example source code file (ModificationWatchpoints.java)

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Java - Java tags/keywords

byteval, charval, doubleval, exception, floatval, intval, jdi, longval, modificationwatchpointstarg, mwp, objectval, shortval, string, stringval, util, value

The ModificationWatchpoints.java Java example source code

/*
 * Copyright (c) 2001, 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 4409582
 *  @summary Test all info returned by modification watchpoints
 *
 *  @author Daniel Prusa (or someone in the FFJ group)
 *  @author Robert Field (modified to JDIScaffold)
 *
 *  @library scaffold
 *  @run build JDIScaffold VMConnection
 *  @run compile -g ModificationWatchpoints.java
 *  @run main/othervm ModificationWatchpoints
 */
import com.sun.jdi.*;
import com.sun.jdi.event.*;
import com.sun.jdi.request.*;
import java.util.*;

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

class ModificationWatchpointsTarg {
    public static final int RepeatCount = 3;

    public static final byte ByteVal = -17;
    public static final char CharVal = 'Y';
    public static final short ShortVal = -412;
    public static final int IntVal = -711618;
    public static final long LongVal = 0x1234567890123456L;
    public static final float FloatVal = 7.986f;
    public static final double DoubleVal = 3.14159265358979d;
    public static final String StringVal = "OnceMore";
    public static final Object ObjectVal = new Object();

    static byte sByte;
    static char sChar;
    static short sShort;
    static int sInt;
    static long sLong;
    static float sFloat;
    static double sDouble;
    static String sString;
    static Object sObject;

    byte iByte;
    char iChar;
    short iShort;
    int iInt;
    long iLong;
    float iFloat;
    double iDouble;
    String iString;
    Object iObject;

    void iByteSet() {
        iByte = ByteVal;
    }

    void iCharSet() {
        iChar = CharVal;
    }

    void iShortSet() {
        iShort = ShortVal;
    }

    void iIntSet() {
        iInt = IntVal;
    }

    void iLongSet() {
        iLong = LongVal;
    }

    void iFloatSet() {
        iFloat = FloatVal;
    }

    void iDoubleSet() {
        iDouble = DoubleVal;
    }

    void iStringSet() {
        iString = StringVal;
    }

    void iObjectSet() {
        iObject = ObjectVal;
    }

    static void sByteSet() {
        sByte = ByteVal;
    }

    static void sCharSet() {
        sChar = CharVal;
    }

    static void sShortSet() {
        sShort = ShortVal;
    }

    static void sIntSet() {
        sInt = IntVal;
    }

    static void sLongSet() {
        sLong = LongVal;
    }

    static void sFloatSet() {
        sFloat = FloatVal;
    }

    static void sDoubleSet() {
        sDouble = DoubleVal;
    }

    static void sStringSet() {
        sString = StringVal;
    }

    static void sObjectSet() {
        sObject = ObjectVal;
    }

    void iUpdate(){
        iByteSet();
        iCharSet();
        iShortSet();
        iIntSet();
        iLongSet();
        iFloatSet();
        iDoubleSet();
        iStringSet();
        iObjectSet();
    }

    static void sUpdate(){
        sByteSet();
        sCharSet();
        sShortSet();
        sIntSet();
        sLongSet();
        sFloatSet();
        sDoubleSet();
        sStringSet();
        sObjectSet();
    }

    public static void main(String[] args){
        ModificationWatchpointsTarg targ = new ModificationWatchpointsTarg();
        for (int i = RepeatCount; i > 0; i--) {
            sUpdate();
            targ.iUpdate();
        }
    }
}

public class ModificationWatchpoints extends TestScaffold {
    ReferenceType targ;
    List allMWP = new ArrayList();

    ModificationWatchpoints (String args[]) {
        super(args);
    }

    public static void main(String[] args)      throws Exception {
        new ModificationWatchpoints(args).startTests();
    }

    /********** event handlers **********/

    public void fieldModified(ModificationWatchpointEvent event) {
        MWP mwp = (MWP)event.request().getProperty("executor");
        mwp.fieldModified(event);
    }


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

    void set(String fieldName, String valString) {
        Value val = targ.getValue(targ.fieldByName(valString));
        MWP mwp = new MWP("ModificationWatchpointsTarg", fieldName, val);
        allMWP.add(mwp);
        mwp.set();
    }

    protected void runTests() throws Exception {
        /*
         * Get to the top of main():
         */
        BreakpointEvent bpe = startToMain("ModificationWatchpointsTarg");
        targ = bpe.location().declaringType();

        /*
         * Set watchpoints
         */
        set("iByte", "ByteVal");
        set("iChar", "CharVal");
        set("iShort", "ShortVal");
        set("iInt", "IntVal");
        set("iLong", "LongVal");
        set("iFloat", "FloatVal");
        set("iDouble", "DoubleVal");
        set("iString", "StringVal");
        set("iObject", "ObjectVal");

        set("sByte", "ByteVal");
        set("sChar", "CharVal");
        set("sShort", "ShortVal");
        set("sInt", "IntVal");
        set("sLong", "LongVal");
        set("sFloat", "FloatVal");
        set("sDouble", "DoubleVal");
        set("sString", "StringVal");
        set("sObject", "ObjectVal");

        listenUntilVMDisconnect();

        if (!testFailed) {
            for (Iterator it = allMWP.iterator(); it.hasNext();) {
                MWP mwp = (MWP)it.next();
                mwp.checkEventCounts(ModificationWatchpointsTarg.RepeatCount);
            }
        }

        if (!testFailed) {
            println("ModificationWatchpoints: passed");
        } else {
            throw new Exception("ModificationWatchpoints: failed");
        }
    }

    /********** request wrapper **********/

    class MWP {
        private final String className;
        private final String fieldName;
        private final Value expectedValue;
        public int eventCount = 0;
        public boolean failed = false;

        public MWP(String className, String fieldName, Value value) {
            this.className = className;
            this.fieldName = fieldName;
            this.expectedValue = value;
        }

        /*
         * Sets watchpoint with specified properties.
         */
        public void set() {
            List classes = vm().classesByName(className);
            if (classes.size() != 1) {
                failure("Expected one class named " + className + " got " + classes.size());
            }

            set ((ReferenceType)classes.get(0));
        }

        /**
         * Sets watchpoint for given class.
         */
        public void set(ReferenceType clazz) {
            Field f = clazz.fieldByName(fieldName);
            ModificationWatchpointRequest mwr =
                       eventRequestManager().createModificationWatchpointRequest(f);
            mwr.putProperty("executor", this);
            mwr.enable();
            println("set watchpoint: " + className +"." + f);
        }

        public void fieldModified(ModificationWatchpointEvent event) {
            Value val = event.valueToBe();
           println("Watchpoint reached: " + className + "." + fieldName +
                   ", new value: " + val);
            if (!val.equals(expectedValue)) {
                failure("FAILURE: value should be: " +
                        expectedValue.getClass() + ":" + expectedValue +
                        " has - " + val.getClass() + ":" + val);
            }
            if (!event.location().method().name().equals(fieldName + "Set")) {
                failure("FAILURE: occurred in wrong place: " + event.location());
            }
            eventCount++;
        }

        public void checkEventCounts(int expectedCount) {
            if (eventCount != expectedCount) {
                failure(className + "." + fieldName +
                        " - only got " + eventCount + " events");
            }
        }

    } // MWP inner class .................
}