--- a/hotspot/test/runtime/7158988/TestPostFieldModification.java	Thu Apr 05 14:16:23 2012 +0200
+++ b/hotspot/test/runtime/7158988/TestPostFieldModification.java	Thu Apr 12 22:03:05 2012 -0400
@@ -21,229 +21,38 @@
  * questions.
  */
 
-/*
- * @test FieldMonitor.java
- * @bug 7158988
- * @summary verify jvm does not crash while debugging
- * @run shell TestFieldMonitor.sh
- * @author axel.siebenborn@sap.com
- */
-import java.io.BufferedReader;
-import java.io.IOException;
-import java.io.InputStream;
-import java.io.InputStreamReader;
-import java.io.OutputStream;
-import java.io.OutputStreamWriter;
-import java.io.Reader;
-import java.io.Writer;
-import java.util.Iterator;
-import java.util.List;
-import java.util.Map;
+public class TestPostFieldModification {
 
-import com.sun.jdi.Bootstrap;
-import com.sun.jdi.Field;
-import com.sun.jdi.ReferenceType;
-import com.sun.jdi.VirtualMachine;
-import com.sun.jdi.connect.Connector;
-import com.sun.jdi.connect.IllegalConnectorArgumentsException;
-import com.sun.jdi.connect.LaunchingConnector;
-import com.sun.jdi.connect.VMStartException;
-import com.sun.jdi.event.ClassPrepareEvent;
-import com.sun.jdi.event.Event;
-import com.sun.jdi.event.EventQueue;
-import com.sun.jdi.event.EventSet;
-import com.sun.jdi.event.ModificationWatchpointEvent;
-import com.sun.jdi.event.VMDeathEvent;
-import com.sun.jdi.event.VMDisconnectEvent;
-import com.sun.jdi.request.ClassPrepareRequest;
-import com.sun.jdi.request.EventRequest;
-import com.sun.jdi.request.EventRequestManager;
-import com.sun.jdi.request.ModificationWatchpointRequest;
+  public String value;  // watch modification of value
 
-public class FieldMonitor {
-
-  public static final String CLASS_NAME = "TestPostFieldModification";
-  public static final String FIELD_NAME = "value";
-  public static final String ARGUMENTS = "-Xshare:off -XX:+PrintGC";
-
-  public static void main(String[] args)
-      throws IOException, InterruptedException {
-
-    StringBuffer sb = new StringBuffer();
+  public static void main(String[] args){
 
-    for (int i=0; i < args.length; i++) {
-        sb.append(' ');
-        sb.append(args[i]);
-    }
-    //VirtualMachine vm = launchTarget(sb.toString());
-    VirtualMachine vm = launchTarget(CLASS_NAME);
-
-    System.out.println("Vm launched");
-    // set watch field on already loaded classes
-    List<ReferenceType> referenceTypes = vm
-        .classesByName(CLASS_NAME);
-    for (ReferenceType refType : referenceTypes) {
-      addFieldWatch(vm, refType);
-    }
-    // watch for loaded classes
-    addClassWatch(vm);
-
-    // process events
-    EventQueue eventQueue = vm.eventQueue();
-    // resume the vm
-
-    Process process = vm.process();
-
-
-    // Copy target's output and error to our output and error.
-    Thread outThread = new StreamRedirectThread("out reader", process.getInputStream());
-    Thread errThread = new StreamRedirectThread("error reader", process.getErrorStream());
-
-    errThread.start();
-    outThread.start();
-
-
-    vm.resume();
-    boolean connected = true;
-    while (connected) {
-      EventSet eventSet = eventQueue.remove();
-      for (Event event : eventSet) {
-        if (event instanceof VMDeathEvent
-            || event instanceof VMDisconnectEvent) {
-          // exit
-          connected = false;
-        } else if (event instanceof ClassPrepareEvent) {
-          // watch field on loaded class
-          System.out.println("ClassPrepareEvent");
-          ClassPrepareEvent classPrepEvent = (ClassPrepareEvent) event;
-          ReferenceType refType = classPrepEvent
-              .referenceType();
-          addFieldWatch(vm, refType);
-        } else if (event instanceof ModificationWatchpointEvent) {
-          System.out.println("sleep for 500 ms");
-          Thread.sleep(500);
-          System.out.println("resume...");
-
-          ModificationWatchpointEvent modEvent = (ModificationWatchpointEvent) event;
-          System.out.println("old="
-              + modEvent.valueCurrent());
-          System.out.println("new=" + modEvent.valueToBe());
-          System.out.println();
+    System.out.println("Start threads");
+    // this thread modifies the field 'value'
+    new Thread() {
+      TestPostFieldModification test = new TestPostFieldModification();
+      public void run() {
+        test.value="test";
+        for(int i = 0; i < 10; i++) {
+          test.value += new String("_test");
         }
       }
-      eventSet.resume();
-    }
-    // Shutdown begins when event thread terminates
-    try {
-        errThread.join(); // Make sure output is forwarded
-        outThread.join();
-    } catch (InterruptedException exc) {
-        // we don't interrupt
-    }
-  }
-
-  /**
-   * Find a com.sun.jdi.CommandLineLaunch connector
-   */
-  static LaunchingConnector findLaunchingConnector() {
-    List <Connector> connectors = Bootstrap.virtualMachineManager().allConnectors();
-    Iterator <Connector> iter = connectors.iterator();
-    while (iter.hasNext()) {
-      Connector connector = iter.next();
-      if (connector.name().equals("com.sun.jdi.CommandLineLaunch")) {
-        return (LaunchingConnector)connector;
-      }
-    }
-    throw new Error("No launching connector");
-  }
-  /**
-   * Return the launching connector's arguments.
-   */
- static Map <String,Connector.Argument> connectorArguments(LaunchingConnector connector, String mainArgs) {
-      Map<String,Connector.Argument> arguments = connector.defaultArguments();
-      for (String key : arguments.keySet()) {
-        System.out.println(key);
-      }
-
-      Connector.Argument mainArg = (Connector.Argument)arguments.get("main");
-      if (mainArg == null) {
-          throw new Error("Bad launching connector");
-      }
-      mainArg.setValue(mainArgs);
+    }.start();
 
-      Connector.Argument optionsArg = (Connector.Argument)arguments.get("options");
-      if (optionsArg == null) {
-        throw new Error("Bad launching connector");
-      }
-      optionsArg.setValue(ARGUMENTS);
-      return arguments;
-  }
+    // this thread is used to trigger a gc
+    Thread d = new Thread() {
+      public void run() {
+        while(true) {
+          try {
+            Thread.sleep(100);
+          } catch (InterruptedException e) {
 
- static VirtualMachine launchTarget(String mainArgs) {
-    LaunchingConnector connector = findLaunchingConnector();
-    Map  arguments = connectorArguments(connector, mainArgs);
-    try {
-        return (VirtualMachine) connector.launch(arguments);
-    } catch (IOException exc) {
-        throw new Error("Unable to launch target VM: " + exc);
-    } catch (IllegalConnectorArgumentsException exc) {
-        throw new Error("Internal error: " + exc);
-    } catch (VMStartException exc) {
-        throw new Error("Target VM failed to initialize: " +
-                        exc.getMessage());
-    }
-}
-
-
-  private static void addClassWatch(VirtualMachine vm) {
-    EventRequestManager erm = vm.eventRequestManager();
-    ClassPrepareRequest classPrepareRequest = erm
-        .createClassPrepareRequest();
-    classPrepareRequest.addClassFilter(CLASS_NAME);
-    classPrepareRequest.setEnabled(true);
-  }
-
-
-  private static void addFieldWatch(VirtualMachine vm,
-      ReferenceType refType) {
-    EventRequestManager erm = vm.eventRequestManager();
-    Field field = refType.fieldByName(FIELD_NAME);
-    ModificationWatchpointRequest modificationWatchpointRequest = erm
-        .createModificationWatchpointRequest(field);
-    modificationWatchpointRequest.setSuspendPolicy(EventRequest.SUSPEND_EVENT_THREAD);
-    modificationWatchpointRequest.setEnabled(true);
+          }
+          System.gc();
+        }
+      }
+    };
+    d.setDaemon(true);
+    d.start();
   }
 }
-
-class StreamRedirectThread extends Thread {
-
-  private final BufferedReader in;
-
-  private static final int BUFFER_SIZE = 2048;
-
-  /**
-   * Set up for copy.
-   * @param name  Name of the thread
-   * @param in    Stream to copy from
-   * @param out   Stream to copy to
-   */
-  StreamRedirectThread(String name, InputStream in) {
-    super(name);
-    this.in = new BufferedReader(new InputStreamReader(in));
-  }
-
-  /**
-   * Copy.
-   */
-  public void run() {
-    try {
-      String line;
-        while ((line = in.readLine ()) != null) {
-          System.out.println ("testvm: " + line);
-      }
-     System.out.flush();
-    } catch(IOException exc) {
-      System.err.println("Child I/O Transfer - " + exc);
-    }
-  }
-}