test/hotspot/jtreg/vmTestbase/nsk/share/jdi/Debugee.java - platform/libcore - Git at Google

 /*
  * Copyright (c) 2001, 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 nsk.share.jdi;

 import nsk.share.*;
 import nsk.share.jpda.*;

 import com.sun.jdi.*;
 import com.sun.jdi.request.*;
 import com.sun.jdi.event.*;

 import java.util.*;

 /**
  * This class is used to interact with debugee VM using JDI features.
  * <p>
  * This class is wrapper for debugee VM constructed by <code>Binder</code>
  * and it uses <code>com.sun.jdi.VirtualMachine</code> to interact with debugee VM.
  * <p>
  * In addition to the general abities to control of debugee VM process,
  * provided by the base class <code>DebugeeProcess</code>, this class
  * adds also several service methods over the JDI features to simplify interaction
  * with debugee VM (such as finding classes, setting breakpoints,
  * handling events, and so on.).
  *
  * @see Binder
  * @see DebugeeProcess
  */
 abstract public class Debugee extends DebugeeProcess {
     /**
      * Mirror of the debugee VM. This must be initialized by every
      * particular non-abstract class extending Debugee class.
      */
     protected VirtualMachine vm = null;

     /** Binder that created this debugee. */
     protected Binder binder = null;

     /** Argument handler. */
     protected ArgumentHandler argumentHandler = null;

     /** Create new <code>Debugee</code> object for a given binder. */
     protected Debugee (Binder binder) {
         super(binder);
         this.binder = binder;
         this.argumentHandler = (ArgumentHandler)binder.getArgumentHandler();
     }

     /** Setup <code>Debugee</code> object with given VM mirror. */
     public void setupVM(VirtualMachine vm) {
         if (this.vm != null) {
             throw new TestBug("Setting duplicated VM mirror for Debugee object");
         }
         this.vm = vm;
         int traceMode = argumentHandler.getTraceMode();
         if (traceMode != VirtualMachine.TRACE_NONE) {
             display("Setting JDI trace mode to: " + argumentHandler.getTraceModeString());
             setDebugTraceMode(traceMode);
         }
     }

     /** Return <code>Binder</code> of the debugee object. */
     public Binder getBinder() {
         return binder;
     }

     /** Return JDI mirror of the debugee VM. */
     public VirtualMachine VM() {
         return vm;
     }

     /** Return <code>EventRequestManager</code> of the debugee object. */
     public EventRequestManager getEventRequestManager() {
         return vm.eventRequestManager();
     }

     // --------------------------------------------------- //

     /** List of the currently running threads. */
     public ThreadReference[] threads () {
         List list = vm.allThreads();
         int size = list.size();
         ThreadReference array[] = new ThreadReference[size];
         Iterator iterator = list.iterator();
         for (int i = 0; i < size; i++)
             array[i] = (ThreadReference) iterator.next();
         if (iterator.hasNext())
             throw new Oddity("extra element in a list?");
         return array;
     }

     /** List of all types loaded by the debugee VM. */
     public ReferenceType[] classes() {
         return classes(null);
     }

     /**
      * List of all classes of the given <code>name</code> loaded by
      * the debugee VM; or list of all classes, if <code>name</code>
      * is <code>null</code>.
      */
     private ReferenceType[] classes (String name) {
         List list = (name==null)? vm.allClasses(): vm.classesByName(name);
         int size = list.size();
         ReferenceType array[] = new ReferenceType [ size ];
         Iterator iterator = list.iterator();
         for (int i=0; i<size; i++)
             array[i] = (ReferenceType) iterator.next();
         if (iterator.hasNext())
             throw new Oddity("extra element in a list?");
         return array;
     }

     // --------------------------------------------------- //

     /**
      * Return mirror for the only class of the given <code>name</code>
      * loaded by the debugee VM; or throw TestBug exception if there
      * are more than one such class found. TestFailure exception
      * will be thrown in case when mirrors for classes with different
      * names or duplicated mirrors were returned.
      * Return <code>null</code> if there is no such class loaded.
      */
     public ReferenceType classByName (String name) {
         ReferenceType classes[] = this.classes(name);

         // if on first call debuggee doesn't return needed class try get this class one more time after delay to avoid 6446633
         if (classes == null || classes.length == 0) {
             try {
                 Thread.sleep(1000);
             }
             catch(InterruptedException e) {
                 throw new TestBug("Unexpected InterruptedException");
             }

             classes = this.classes(name);
         }

         if (classes == null || classes.length == 0)
             return null;

         // analyze returned mirrors and throw appropriate exception
         if (classes.length > 1) {
             boolean duplicatesFound = false;
             boolean differentNamesFound = false;
             boolean visited[] = new boolean[classes.length];
             complain("Classes that were found for name \"" + name + "\":");
             for(ReferenceType klass : classes) {
                 complain("\t" + klass);
             }
             for(int c = 0; c < classes.length; c++) {
                 if(visited[c]) {
                     continue;
                 }
                 if(!classes[c].name().equals(name)) {
                     differentNamesFound = true;
                     continue;
                 }
                 for(int i = c + 1; i < classes.length; i++) {
                     if(visited[i]) {
                         continue;
                     } else {
                         visited[i] = true;
                     }
                     if(classes[c].classLoader() == classes[i].classLoader()) {
                         duplicatesFound = true;
                     }
                 }
             }
             if(duplicatesFound) {
                 throw new TestFailure("classes with the same name and " +
                                       "loaded with the same class loader " +
                                       "were found.");
             } else if(differentNamesFound) {
                 throw new TestFailure("class with name different from '" + name +
                                       "' was returned by VirutualMachine.classesByName.");
             } else {
                 throw new TestBug("found " + classes.length + " such classes: " + name);
             }
         }
         return classes[0];
     }

     /**
      * Return mirror for the only method of the given <code>refType</code>
      * class in the debugee VM; or throw TestBug exception if there
      * are more than one such method found. Return <code>null</code> if
      * there is no such method found.
      */
     public Method methodByName(ReferenceType refType, String name) {
         List methods = refType.methodsByName(name);
         if (methods == null || methods.isEmpty()) return null;
         if (methods.size() > 1)
             throw new TestBug(
                 "found " + methods.size() + " such methods: " + name);
         Method method = (Method)methods.get(0);
         return method;
     }

     /**
      * Return a currently running thread of the given <code>name</code>; or
      * throw TestBug exception if there are more than one such thread found.
      * Return <code>null</code> if there is no such thread.
      */
     public ThreadReference threadByName (String name) {
         ThreadReference threads[] = this.threads();
         int count = 0, index = -1;
         for (int i = 0; i < threads.length; i++) {
             if (threads[i].name().compareTo(name)==0) {
                 count++;
                 index = i;
             }
         }
         if (count == 0)
             return null;
         if (count > 1)
             throw new TestBug(
                 "found " + count + " such threads: " + name);
         return threads[index];
     }

     // --------------------------------------------------- //

     /**
      * Returns Location object for given line number in specified method or null
      * if no location for this line is found.
      *
      * @param method method mirror containing given line number
      * @param line line number to find location
      */
     public Location getLineLocation(Method method, int line) {
         List locs = null;
         try {
             locs = method.allLineLocations();
         } catch(AbsentInformationException e) {
             throw new TestBug("Unable to find location for line " + line + ": " + e);
         }
         Iterator iter = locs.iterator();
         while (iter.hasNext()) {
             Location location = (Location)iter.next();
             if (location.lineNumber() == line) {
                 return location;
             }
         }
         return null;
     }

     /**
      * Returns Location object for given line number in specified reference type or null
      * if no location for this line is found.
      *
      * @param refType reference type mirror containing given line number
      * @param line line number to find location
      */
     public Location getLineLocation(ReferenceType refType, int line) {
         List locs = null;
         try {
             locs = refType.allLineLocations();
         } catch(AbsentInformationException e) {
             throw new TestBug("Unable to find location for line " + line + ": " + e);
         }
         Iterator iter = locs.iterator();
         while (iter.hasNext()) {
             Location location = (Location)iter.next();
             if (location.lineNumber() == line) {
                 return location;
             }
         }
         return null;
     }

     // --------------------------------------------------- //

     /**
      * Make disabled breakpoint to given location and return BreakpointRequest.
      *
      * @param location location to set breakpoint
      *
      * @see #setBreakpoint(Method, int)
      * @see #setBreakpoint(ReferenceType, String, int)
      */
     public BreakpointRequest makeBreakpoint(Location location) {
         EventRequestManager evm = getEventRequestManager();
         BreakpointRequest request = evm.createBreakpointRequest(location);
         display("Breakpoint set:\n\t" + request);
         return request;
     }

     /**
      * Make disabled breakpoint to given line number in specified method
      * and return BreakpointRequest.
      *
      * @param method method mirror to set breakpoint
      * @param lineNumber line number inside the method
      *
      * @throws Failure if no location found for specified line number
      *
      * @see #makeBreakpoint(Location)
      * @see #makeBreakpoint(ReferenceType, String, int)
      */
     public BreakpointRequest makeBreakpoint(Method method, int lineNumber) {
         Location location = getLineLocation(method, lineNumber);
         if (location == null) {
             throw new Failure("No location found for setting breakpoint to line " + lineNumber);
         }
         return makeBreakpoint(location);
     }

     /**
      * Make disabled breakpoint to given line number for specified method name
      * of the given reference type and return BreakpointRequest.
      *
      * @param refType reference type for specified method
      * @param methodName method name to set breakpoint
      * @param lineNumber line number inside the method
      *
      * @throws Failure if no location found for specified line number
      *
      * @see #makeBreakpoint(Method, int)
      */
     public BreakpointRequest makeBreakpoint(ReferenceType refType,
                                             String methodName, int lineNumber) {
         Method method = methodByName(refType, methodName);
         if (method == null) {
             throw new Failure("No method found for setting breakpoint: " + methodName);
         }
         return makeBreakpoint(method, lineNumber);
     }

     /**
      * Set and enable breakpoint to given line number for specified method
      * and return BreakpointRequest.
      *
      * @param method method mirror to set breakpoint
      * @param lineNumber line number inside the method
      *
      * @throws Failure if no location found for specified line number
      *
      * @see #setBreakpoint(ReferenceType, String, int)
      */
     public BreakpointRequest setBreakpoint(Method method, int lineNumber) {
         BreakpointRequest request = makeBreakpoint(method, lineNumber);
         request.enable();
         return request;
     }

     /**
      * Set and enable breakpoint to given line number for specified method name
      * of the given reference type and return BreakpointRequest.
      *
      * @param refType reference type for specified method
      * @param methodName method name to set breakpoint
      * @param lineNumber line number inside the method
      *
      * @throws Failure if no location found for specified line number
      *
      * @see #setBreakpoint(Method, int)
      */
     public BreakpointRequest setBreakpoint(ReferenceType refType,
                                             String methodName, int lineNumber) {
         BreakpointRequest request = makeBreakpoint(refType, methodName, lineNumber);
         request.enable();
         return request;
     }

     // --------------------------------------------------- //

     /** Suspend the debugee VM. */
     public void suspend() {
         vm.suspend();
     }

     /** Resume the debugee VM. */
     public void resume() {
         vm.resume();
     }

     /** Dispose the debugee VM. */
     public void dispose() {
         vm.dispose();
     }

     /*
      * Set internal JDI tracing mode.
      */
     public void setDebugTraceMode(int traceMode) {
         vm.setDebugTraceMode(traceMode);
     }

     // --------------------------------------------------- //

     /**
      * Wait for the requested event and skip other events.
      *
      * @param request non-null value for events generated by this
      * event request; null value for <code>VMStartEvent</code>.
      * @param timeout timeout in milliseconds to wait for the requested event.
      *
      * @throws InterruptedException if another thread has interrupted this thread
      */
     public Event waitingEvent(EventRequest request, long timeout)
                                                 throws InterruptedException {

         if (request == null) {
             throw new Failure("Null request specified for waiting events: " + request);
         }

         long timeToFinish = System.currentTimeMillis() + timeout;
         long timeLeft = timeout;
         boolean exit = false;

         display("Waiting for event by request:\n\t" + request);

         EventQueue eventQueue = vm.eventQueue();
         while (timeLeft > 0 && !exit) {

             EventSet eventSet = eventQueue.remove(timeLeft);
             if (eventSet == null) {
                 continue;
             }

             EventIterator eventIterator = eventSet.eventIterator();
             while (eventIterator.hasNext()) {

                 Event event = eventIterator.nextEvent();
                 EventRequest eventRequest = event.request();

                 if (request == eventRequest || request.equals(eventRequest)) {
                     display("Got requested event:\n\t" + event);
                     return event;
                 } else if (event instanceof VMDeathEvent) {
                     display("Ignore unexpected VMDeathEvent");
                 } else if (event instanceof VMDisconnectEvent) {
                     display("Got unexpected VMDisconnectEvent");
                     exit = true;
                     break;
                 } else {
                     display("Ignore unexpected event:\n\t" + event);
                 } // if

             } // while

             timeLeft = timeToFinish - System.currentTimeMillis();

         } // while

         return null;
     }

     /*
      * Wait for VM to initialize by receiving initial VM_START event for specified timeout.
      */
     public void waitForVMInit(long timeout) {
         waitForVMInit(vm ,log, timeout);
     }

     /*
      * This static method is also used by nsk.share.jdi.ConnectorTest
      */
     static public void waitForVMInit(VirtualMachine vm, Log log, long timeout) {
         try {
             EventSet eventSet = vm.eventQueue().remove(timeout);
             if (eventSet == null) {
                 throw new Failure("No VMStartEvent received for timeout: " + timeout + " ms");
             }
             EventIterator iterator = eventSet.eventIterator();
             while (iterator.hasNext()) {
                 Event event = iterator.nextEvent();
                 if (event == null) {
                     throw new Failure("Null event received instead of VMStartEvent");
                 }
                 if (event instanceof VMStartEvent) {
                     log.display("Initial VMStartEvent received: " + event);
                 } else {
                     throw new Failure("Unexpected event received instead of VMStartEvent: " + event);
                 }
             }
             int suspendPolicy = eventSet.suspendPolicy();
             if (suspendPolicy != EventRequest.SUSPEND_ALL) {
                 throw new Failure("Suspend policy of VMStartEvent is not SUSPEND_ALL: " + suspendPolicy);
             }
         } catch (InterruptedException e) {
             e.printStackTrace(log.getOutStream());
             throw new Failure("Thread interrupted while waiting for VMStartEvent:\n\t" + e);
         }
     }

     // --------------------------------------------------- //

     /**
      * Bind to debuggee VM using <code>Binder</code> and make initial
      * synchronization via IOPipe.
      *
      * @param argHandler command line arguments handler to make <code>Binder</code> object
      * @param log <code>Log</code> object to log messages
      * @param mainClassName main class of debugee
      *
      * @throws Failure if there were problems with binding to debuggee VM
      *
      * @see Binder#bindToDebugee(String)
      */
     public static Debugee prepareDebugee(ArgumentHandler argHandler, Log log,
                                                 String mainClassName) {
         Binder binder = new Binder(argHandler, log);
         Debugee debugee = binder.bindToDebugee(mainClassName);

         debugee.createIOPipe();

         debugee.redirectStderr(log, DEBUGEE_STDERR_LOG_PREFIX);
         debugee.resume();

         debugee.receiveExpectedSignal("ready");

         return debugee;
     }

     /**
      * Send <code>"quit"</code> signal, wait for debugee VM exit and check exit.
      *
      * @throws Failure if exit status is not <code>Consts.JCK_STATUS_BASE</code>
      *
      * @see #endDebugee()
      */
     public void quit() {
         sendSignal("quit");
         int status = endDebugee();
         if ( status != Consts.JCK_STATUS_BASE ) {
             throw new Failure("Got unexpected debugee VM exit status: " + status
                                 + " (not " + Consts.JCK_STATUS_BASE + ")");
         }
         display("Got expected debugee VM exit status: " + status);
     }

     /*
      * Dispose debuggee VM, wait for it to exit, close all resources and return
      * exit status code.
      */
     public int endDebugee() {
         if (vm != null) {
             try {
                 vm.dispose();
             } catch (VMDisconnectedException ignore) {
             }
             vm = null;
         }
         return waitFor();
     }

     /*
      * Print information about all threads in debuggee VM
      */
     protected void printThreadsInfo(VirtualMachine vm)  {
         try {
             log.display("------------ Try to print debuggee threads before killing process ------------");
             if (vm == null) {
                 log.display("Can't print threads info because 'vm' is null");
                 return;
             }
             List<ThreadReference> threads = vm.allThreads();
             log.display("Threads: " + threads);
             log.display("Total threads: " + threads.size());
             for (ThreadReference thread : threads) {
                 log.display("\nThread: " + thread.name());
                 log.display("Is suspended: " + thread.isSuspended());
                 log.display("Is at breakpoint: " + thread.isAtBreakpoint());
                 boolean wasSuspended = false;
                 try {
                     if (!thread.isSuspended()) {
                         log.display("\n suspend thread to get its stack \n");
                         thread.suspend();
                         wasSuspended = true;
                     }
                     log.display("Stack frame count: " + thread.frameCount());
                     if (thread.frameCount() > 0) {
                         log.display("Frames:");
                         for (StackFrame frame : thread.frames()) {
                             Location location = frame.location();
                             log.display(location.declaringType().name() + "." + location.method().name() + ", line: " + location.lineNumber());
                         }
                     }
                 } finally {
                     if (wasSuspended) {
                         log.display("\n resume thread \n");
                         thread.resume();
                     }
                 }
             }
             log.display("----------------------------------------------------------------------");
         } catch (Throwable t) {
             log.complain("");
             t.printStackTrace(log.getOutStream());
         }
     }

     /**
      * Force debugge VM to exit using JDI interface if possible.
      */
     protected void killDebugee() {
         try {
             // print information about debuggee threads to simplify failure analysis
             printThreadsInfo(vm);
         } finally {
             if (vm != null) {
                 try {
                     display("Killing debuggee by forcing target VM to exit");
                     vm.exit(97);
                     display("Debugee VM successfully forced to exit");
                     vm = null;
                 } catch (VMDisconnectedException e) {
                     display("Ignore VMDisconnectedException while forcing debuggee VM to exit:\n\t"
                             + e);
                 }
             }
         }
     }

     public boolean isJFR_active() {
         String opts = argumentHandler.getLaunchOptions();
         int jfrPos = opts.indexOf("-XX:+FlightRecorder");

         if (jfrPos >= 0)
             return true;
         else
             return false;
     }
 }
	/*
	* Copyright (c) 2001, 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 nsk.share.jdi;

	import nsk.share.*;
	import nsk.share.jpda.*;

	import com.sun.jdi.*;
	import com.sun.jdi.request.*;
	import com.sun.jdi.event.*;

	import java.util.*;

	/**
	* This class is used to interact with debugee VM using JDI features.
	* <p>
	* This class is wrapper for debugee VM constructed by <code>Binder</code>
	* and it uses <code>com.sun.jdi.VirtualMachine</code> to interact with debugee VM.
	* <p>
	* In addition to the general abities to control of debugee VM process,
	* provided by the base class <code>DebugeeProcess</code>, this class
	* adds also several service methods over the JDI features to simplify interaction
	* with debugee VM (such as finding classes, setting breakpoints,
	* handling events, and so on.).
	*
	* @see Binder
	* @see DebugeeProcess
	*/
	abstract public class Debugee extends DebugeeProcess {
	/**
	* Mirror of the debugee VM. This must be initialized by every
	* particular non-abstract class extending Debugee class.
	*/
	protected VirtualMachine vm = null;

	/** Binder that created this debugee. */
	protected Binder binder = null;

	/** Argument handler. */
	protected ArgumentHandler argumentHandler = null;

	/** Create new <code>Debugee</code> object for a given binder. */
	protected Debugee (Binder binder) {
	super(binder);
	this.binder = binder;
	this.argumentHandler = (ArgumentHandler)binder.getArgumentHandler();
	}

	/** Setup <code>Debugee</code> object with given VM mirror. */
	public void setupVM(VirtualMachine vm) {
	if (this.vm != null) {
	throw new TestBug("Setting duplicated VM mirror for Debugee object");
	}
	this.vm = vm;
	int traceMode = argumentHandler.getTraceMode();
	if (traceMode != VirtualMachine.TRACE_NONE) {
	display("Setting JDI trace mode to: " + argumentHandler.getTraceModeString());
	setDebugTraceMode(traceMode);
	}
	}

	/** Return <code>Binder</code> of the debugee object. */
	public Binder getBinder() {
	return binder;
	}

	/** Return JDI mirror of the debugee VM. */
	public VirtualMachine VM() {
	return vm;
	}

	/** Return <code>EventRequestManager</code> of the debugee object. */
	public EventRequestManager getEventRequestManager() {
	return vm.eventRequestManager();
	}

	// --------------------------------------------------- //

	/** List of the currently running threads. */
	public ThreadReference[] threads () {
	List list = vm.allThreads();
	int size = list.size();
	ThreadReference array[] = new ThreadReference[size];
	Iterator iterator = list.iterator();
	for (int i = 0; i < size; i++)
	array[i] = (ThreadReference) iterator.next();
	if (iterator.hasNext())
	throw new Oddity("extra element in a list?");
	return array;
	}

	/** List of all types loaded by the debugee VM. */
	public ReferenceType[] classes() {
	return classes(null);
	}

	/**
	* List of all classes of the given <code>name</code> loaded by
	* the debugee VM; or list of all classes, if <code>name</code>
	* is <code>null</code>.
	*/
	private ReferenceType[] classes (String name) {
	List list = (name==null)? vm.allClasses(): vm.classesByName(name);
	int size = list.size();
	ReferenceType array[] = new ReferenceType [ size ];
	Iterator iterator = list.iterator();
	for (int i=0; i<size; i++)
	array[i] = (ReferenceType) iterator.next();
	if (iterator.hasNext())
	throw new Oddity("extra element in a list?");
	return array;
	}

	// --------------------------------------------------- //

	/**
	* Return mirror for the only class of the given <code>name</code>
	* loaded by the debugee VM; or throw TestBug exception if there
	* are more than one such class found. TestFailure exception
	* will be thrown in case when mirrors for classes with different
	* names or duplicated mirrors were returned.
	* Return <code>null</code> if there is no such class loaded.
	*/
	public ReferenceType classByName (String name) {
	ReferenceType classes[] = this.classes(name);

	// if on first call debuggee doesn't return needed class try get this class one more time after delay to avoid 6446633
	if (classes == null \|\| classes.length == 0) {
	try {
	Thread.sleep(1000);
	}
	catch(InterruptedException e) {
	throw new TestBug("Unexpected InterruptedException");
	}

	classes = this.classes(name);
	}

	if (classes == null \|\| classes.length == 0)
	return null;

	// analyze returned mirrors and throw appropriate exception
	if (classes.length > 1) {
	boolean duplicatesFound = false;
	boolean differentNamesFound = false;
	boolean visited[] = new boolean[classes.length];
	complain("Classes that were found for name \"" + name + "\":");
	for(ReferenceType klass : classes) {
	complain("\t" + klass);
	}
	for(int c = 0; c < classes.length; c++) {
	if(visited[c]) {
	continue;
	}
	if(!classes[c].name().equals(name)) {
	differentNamesFound = true;
	continue;
	}
	for(int i = c + 1; i < classes.length; i++) {
	if(visited[i]) {
	continue;
	} else {
	visited[i] = true;
	}
	if(classes[c].classLoader() == classes[i].classLoader()) {
	duplicatesFound = true;
	}
	}
	}
	if(duplicatesFound) {
	throw new TestFailure("classes with the same name and " +
	"loaded with the same class loader " +
	"were found.");
	} else if(differentNamesFound) {
	throw new TestFailure("class with name different from '" + name +
	"' was returned by VirutualMachine.classesByName.");
	} else {
	throw new TestBug("found " + classes.length + " such classes: " + name);
	}
	}
	return classes[0];
	}

	/**
	* Return mirror for the only method of the given <code>refType</code>
	* class in the debugee VM; or throw TestBug exception if there
	* are more than one such method found. Return <code>null</code> if
	* there is no such method found.
	*/
	public Method methodByName(ReferenceType refType, String name) {
	List methods = refType.methodsByName(name);
	if (methods == null \|\| methods.isEmpty()) return null;
	if (methods.size() > 1)
	throw new TestBug(
	"found " + methods.size() + " such methods: " + name);
	Method method = (Method)methods.get(0);
	return method;
	}

	/**
	* Return a currently running thread of the given <code>name</code>; or
	* throw TestBug exception if there are more than one such thread found.
	* Return <code>null</code> if there is no such thread.
	*/
	public ThreadReference threadByName (String name) {
	ThreadReference threads[] = this.threads();
	int count = 0, index = -1;
	for (int i = 0; i < threads.length; i++) {
	if (threads[i].name().compareTo(name)==0) {
	count++;
	index = i;
	}
	}
	if (count == 0)
	return null;
	if (count > 1)
	throw new TestBug(
	"found " + count + " such threads: " + name);
	return threads[index];
	}

	// --------------------------------------------------- //

	/**
	* Returns Location object for given line number in specified method or null
	* if no location for this line is found.
	*
	* @param method method mirror containing given line number
	* @param line line number to find location
	*/
	public Location getLineLocation(Method method, int line) {
	List locs = null;
	try {
	locs = method.allLineLocations();
	} catch(AbsentInformationException e) {
	throw new TestBug("Unable to find location for line " + line + ": " + e);
	}
	Iterator iter = locs.iterator();
	while (iter.hasNext()) {
	Location location = (Location)iter.next();
	if (location.lineNumber() == line) {
	return location;
	}
	}
	return null;
	}

	/**
	* Returns Location object for given line number in specified reference type or null
	* if no location for this line is found.
	*
	* @param refType reference type mirror containing given line number
	* @param line line number to find location
	*/
	public Location getLineLocation(ReferenceType refType, int line) {
	List locs = null;
	try {
	locs = refType.allLineLocations();
	} catch(AbsentInformationException e) {
	throw new TestBug("Unable to find location for line " + line + ": " + e);
	}
	Iterator iter = locs.iterator();
	while (iter.hasNext()) {
	Location location = (Location)iter.next();
	if (location.lineNumber() == line) {
	return location;
	}
	}
	return null;
	}

	// --------------------------------------------------- //

	/**
	* Make disabled breakpoint to given location and return BreakpointRequest.
	*
	* @param location location to set breakpoint
	*
	* @see #setBreakpoint(Method, int)
	* @see #setBreakpoint(ReferenceType, String, int)
	*/
	public BreakpointRequest makeBreakpoint(Location location) {
	EventRequestManager evm = getEventRequestManager();
	BreakpointRequest request = evm.createBreakpointRequest(location);
	display("Breakpoint set:\n\t" + request);
	return request;
	}

	/**
	* Make disabled breakpoint to given line number in specified method
	* and return BreakpointRequest.
	*
	* @param method method mirror to set breakpoint
	* @param lineNumber line number inside the method
	*
	* @throws Failure if no location found for specified line number
	*
	* @see #makeBreakpoint(Location)
	* @see #makeBreakpoint(ReferenceType, String, int)
	*/
	public BreakpointRequest makeBreakpoint(Method method, int lineNumber) {
	Location location = getLineLocation(method, lineNumber);
	if (location == null) {
	throw new Failure("No location found for setting breakpoint to line " + lineNumber);
	}
	return makeBreakpoint(location);
	}

	/**
	* Make disabled breakpoint to given line number for specified method name
	* of the given reference type and return BreakpointRequest.
	*
	* @param refType reference type for specified method
	* @param methodName method name to set breakpoint
	* @param lineNumber line number inside the method
	*
	* @throws Failure if no location found for specified line number
	*
	* @see #makeBreakpoint(Method, int)
	*/
	public BreakpointRequest makeBreakpoint(ReferenceType refType,
	String methodName, int lineNumber) {
	Method method = methodByName(refType, methodName);
	if (method == null) {
	throw new Failure("No method found for setting breakpoint: " + methodName);
	}
	return makeBreakpoint(method, lineNumber);
	}

	/**
	* Set and enable breakpoint to given line number for specified method
	* and return BreakpointRequest.
	*
	* @param method method mirror to set breakpoint
	* @param lineNumber line number inside the method
	*
	* @throws Failure if no location found for specified line number
	*
	* @see #setBreakpoint(ReferenceType, String, int)
	*/
	public BreakpointRequest setBreakpoint(Method method, int lineNumber) {
	BreakpointRequest request = makeBreakpoint(method, lineNumber);
	request.enable();
	return request;
	}

	/**
	* Set and enable breakpoint to given line number for specified method name
	* of the given reference type and return BreakpointRequest.
	*
	* @param refType reference type for specified method
	* @param methodName method name to set breakpoint
	* @param lineNumber line number inside the method
	*
	* @throws Failure if no location found for specified line number
	*
	* @see #setBreakpoint(Method, int)
	*/
	public BreakpointRequest setBreakpoint(ReferenceType refType,
	String methodName, int lineNumber) {
	BreakpointRequest request = makeBreakpoint(refType, methodName, lineNumber);
	request.enable();
	return request;
	}

	// --------------------------------------------------- //

	/** Suspend the debugee VM. */
	public void suspend() {
	vm.suspend();
	}

	/** Resume the debugee VM. */
	public void resume() {
	vm.resume();
	}

	/** Dispose the debugee VM. */
	public void dispose() {
	vm.dispose();
	}

	/*
	* Set internal JDI tracing mode.
	*/
	public void setDebugTraceMode(int traceMode) {
	vm.setDebugTraceMode(traceMode);
	}

	// --------------------------------------------------- //

	/**
	* Wait for the requested event and skip other events.
	*
	* @param request non-null value for events generated by this
	* event request; null value for <code>VMStartEvent</code>.
	* @param timeout timeout in milliseconds to wait for the requested event.
	*
	* @throws InterruptedException if another thread has interrupted this thread
	*/
	public Event waitingEvent(EventRequest request, long timeout)
	throws InterruptedException {

	if (request == null) {
	throw new Failure("Null request specified for waiting events: " + request);
	}

	long timeToFinish = System.currentTimeMillis() + timeout;
	long timeLeft = timeout;
	boolean exit = false;

	display("Waiting for event by request:\n\t" + request);

	EventQueue eventQueue = vm.eventQueue();
	while (timeLeft > 0 && !exit) {

	EventSet eventSet = eventQueue.remove(timeLeft);
	if (eventSet == null) {
	continue;
	}

	EventIterator eventIterator = eventSet.eventIterator();
	while (eventIterator.hasNext()) {

	Event event = eventIterator.nextEvent();
	EventRequest eventRequest = event.request();

	if (request == eventRequest \|\| request.equals(eventRequest)) {
	display("Got requested event:\n\t" + event);
	return event;
	} else if (event instanceof VMDeathEvent) {
	display("Ignore unexpected VMDeathEvent");
	} else if (event instanceof VMDisconnectEvent) {
	display("Got unexpected VMDisconnectEvent");
	exit = true;
	break;
	} else {
	display("Ignore unexpected event:\n\t" + event);
	} // if

	} // while

	timeLeft = timeToFinish - System.currentTimeMillis();

	} // while

	return null;
	}

	/*
	* Wait for VM to initialize by receiving initial VM_START event for specified timeout.
	*/
	public void waitForVMInit(long timeout) {
	waitForVMInit(vm ,log, timeout);
	}

	/*
	* This static method is also used by nsk.share.jdi.ConnectorTest
	*/
	static public void waitForVMInit(VirtualMachine vm, Log log, long timeout) {
	try {
	EventSet eventSet = vm.eventQueue().remove(timeout);
	if (eventSet == null) {
	throw new Failure("No VMStartEvent received for timeout: " + timeout + " ms");
	}
	EventIterator iterator = eventSet.eventIterator();
	while (iterator.hasNext()) {
	Event event = iterator.nextEvent();
	if (event == null) {
	throw new Failure("Null event received instead of VMStartEvent");
	}
	if (event instanceof VMStartEvent) {
	log.display("Initial VMStartEvent received: " + event);
	} else {
	throw new Failure("Unexpected event received instead of VMStartEvent: " + event);
	}
	}
	int suspendPolicy = eventSet.suspendPolicy();
	if (suspendPolicy != EventRequest.SUSPEND_ALL) {
	throw new Failure("Suspend policy of VMStartEvent is not SUSPEND_ALL: " + suspendPolicy);
	}
	} catch (InterruptedException e) {
	e.printStackTrace(log.getOutStream());
	throw new Failure("Thread interrupted while waiting for VMStartEvent:\n\t" + e);
	}
	}

	// --------------------------------------------------- //

	/**
	* Bind to debuggee VM using <code>Binder</code> and make initial
	* synchronization via IOPipe.
	*
	* @param argHandler command line arguments handler to make <code>Binder</code> object
	* @param log <code>Log</code> object to log messages
	* @param mainClassName main class of debugee
	*
	* @throws Failure if there were problems with binding to debuggee VM
	*
	* @see Binder#bindToDebugee(String)
	*/
	public static Debugee prepareDebugee(ArgumentHandler argHandler, Log log,
	String mainClassName) {
	Binder binder = new Binder(argHandler, log);
	Debugee debugee = binder.bindToDebugee(mainClassName);

	debugee.createIOPipe();

	debugee.redirectStderr(log, DEBUGEE_STDERR_LOG_PREFIX);
	debugee.resume();

	debugee.receiveExpectedSignal("ready");

	return debugee;
	}

	/**
	* Send <code>"quit"</code> signal, wait for debugee VM exit and check exit.
	*
	* @throws Failure if exit status is not <code>Consts.JCK_STATUS_BASE</code>
	*
	* @see #endDebugee()
	*/
	public void quit() {
	sendSignal("quit");
	int status = endDebugee();
	if ( status != Consts.JCK_STATUS_BASE ) {
	throw new Failure("Got unexpected debugee VM exit status: " + status
	+ " (not " + Consts.JCK_STATUS_BASE + ")");
	}
	display("Got expected debugee VM exit status: " + status);
	}

	/*
	* Dispose debuggee VM, wait for it to exit, close all resources and return
	* exit status code.
	*/
	public int endDebugee() {
	if (vm != null) {
	try {
	vm.dispose();
	} catch (VMDisconnectedException ignore) {
	}
	vm = null;
	}
	return waitFor();
	}

	/*
	* Print information about all threads in debuggee VM
	*/
	protected void printThreadsInfo(VirtualMachine vm) {
	try {
	log.display("------------ Try to print debuggee threads before killing process ------------");
	if (vm == null) {
	log.display("Can't print threads info because 'vm' is null");
	return;
	}
	List<ThreadReference> threads = vm.allThreads();
	log.display("Threads: " + threads);
	log.display("Total threads: " + threads.size());
	for (ThreadReference thread : threads) {
	log.display("\nThread: " + thread.name());
	log.display("Is suspended: " + thread.isSuspended());
	log.display("Is at breakpoint: " + thread.isAtBreakpoint());
	boolean wasSuspended = false;
	try {
	if (!thread.isSuspended()) {
	log.display("\n suspend thread to get its stack \n");
	thread.suspend();
	wasSuspended = true;
	}
	log.display("Stack frame count: " + thread.frameCount());
	if (thread.frameCount() > 0) {
	log.display("Frames:");
	for (StackFrame frame : thread.frames()) {
	Location location = frame.location();
	log.display(location.declaringType().name() + "." + location.method().name() + ", line: " + location.lineNumber());
	}
	}
	} finally {
	if (wasSuspended) {
	log.display("\n resume thread \n");
	thread.resume();
	}
	}
	}
	log.display("----------------------------------------------------------------------");
	} catch (Throwable t) {
	log.complain("");
	t.printStackTrace(log.getOutStream());
	}
	}

	/**
	* Force debugge VM to exit using JDI interface if possible.
	*/
	protected void killDebugee() {
	try {
	// print information about debuggee threads to simplify failure analysis
	printThreadsInfo(vm);
	} finally {
	if (vm != null) {
	try {
	display("Killing debuggee by forcing target VM to exit");
	vm.exit(97);
	display("Debugee VM successfully forced to exit");
	vm = null;
	} catch (VMDisconnectedException e) {
	display("Ignore VMDisconnectedException while forcing debuggee VM to exit:\n\t"
	+ e);
	}
	}
	}
	}

	public boolean isJFR_active() {
	String opts = argumentHandler.getLaunchOptions();
	int jfrPos = opts.indexOf("-XX:+FlightRecorder");

	if (jfrPos >= 0)
	return true;
	else
	return false;
	}
	}