Improvement of debugger plugin. Debugger itself became multithreaded

teavm-chrome-rdp/src/main/java/org/teavm/chromerdp/ChromeRDPDebugger.java

@@ -2,6 +2,9 @@ package org.teavm.chromerdp;
 
 import java.io.IOException;
 import java.util.*;
+import java.util.concurrent.ConcurrentHashMap;
+import java.util.concurrent.ConcurrentMap;
+import java.util.concurrent.atomic.AtomicInteger;
 import org.codehaus.jackson.JsonNode;
 import org.codehaus.jackson.map.ObjectMapper;
 import org.teavm.chromerdp.data.CallFrameDTO;
@@ -16,16 +19,21 @@ import org.teavm.debugging.*;
  * @author Alexey Andreev <konsoletyper@gmail.com>
  */
 public class ChromeRDPDebugger implements JavaScriptDebugger, ChromeRDPExchangeConsumer {
+    private static final Object dummy = new Object();
     private ChromeRDPExchange exchange;
-    private List<JavaScriptDebuggerListener> listeners = new ArrayList<>();
+    private ConcurrentMap<JavaScriptDebuggerListener, Object> listeners = new ConcurrentHashMap<>();
-    private Set<RDPBreakpoint> breakpoints = new HashSet<>();
+    private ConcurrentMap<RDPBreakpoint, Object> breakpoints = new ConcurrentHashMap<>();
-    private RDPCallFrame[] callStack = new RDPCallFrame[0];
+    private volatile RDPCallFrame[] callStack = new RDPCallFrame[0];
-    private Map<String, String> scripts = new HashMap<>();
+    private ConcurrentMap<String, String> scripts = new ConcurrentHashMap<>();
-    private Map<String, String> scriptIds = new HashMap<>();
+    private ConcurrentMap<String, String> scriptIds = new ConcurrentHashMap<>();
     private boolean suspended = false;
     private ObjectMapper mapper = new ObjectMapper();
-    private Map<Integer, ResponseHandler> responseHandlers = new HashMap<>();
+    private ConcurrentMap<Integer, ResponseHandler> responseHandlers = new ConcurrentHashMap<>();
-    private int messageIdGenerator;
+    private AtomicInteger messageIdGenerator = new AtomicInteger();
+
+    private List<JavaScriptDebuggerListener> getListeners() {
+        return new ArrayList<>(listeners.keySet());
+    }
 
     @Override
     public void setExchange(ChromeRDPExchange exchange) {
@@ -37,15 +45,15 @@ public class ChromeRDPDebugger implements JavaScriptDebugger, ChromeRDPExchangeC
         }
         this.exchange = exchange;
         if (exchange != null) {
-            for (RDPBreakpoint breakpoint : breakpoints) {
+            for (RDPBreakpoint breakpoint : breakpoints.keySet().toArray(new RDPBreakpoint[0])) {
                 updateBreakpoint(breakpoint);
             }
-            for (JavaScriptDebuggerListener listener : listeners) {
+            for (JavaScriptDebuggerListener listener : getListeners()) {
                 listener.attached();
             }
         } else {
             suspended = false;
-            for (JavaScriptDebuggerListener listener : listeners) {
+            for (JavaScriptDebuggerListener listener : getListeners()) {
                 listener.detached();
             }
         }
@@ -86,7 +94,7 @@ public class ChromeRDPDebugger implements JavaScriptDebugger, ChromeRDPExchangeC
             callStack[i] = map(callFrameDTOs[i]);
         }
         this.callStack = callStack;
-        for (JavaScriptDebuggerListener listener : listeners) {
+        for (JavaScriptDebuggerListener listener : getListeners()) {
             listener.paused();
         }
     }
@@ -94,18 +102,17 @@ public class ChromeRDPDebugger implements JavaScriptDebugger, ChromeRDPExchangeC
     private synchronized void fireResumed() {
         suspended = false;
         callStack = null;
-        for (JavaScriptDebuggerListener listener : listeners) {
+        for (JavaScriptDebuggerListener listener : getListeners()) {
             listener.resumed();
         }
     }
 
     private synchronized void scriptParsed(ScriptParsedNotification params) {
-        if (scripts.containsKey(params.getScriptId())) {
+        if (scripts.putIfAbsent(params.getScriptId(), params.getUrl()) != null) {
             return;
         }
-        scripts.put(params.getScriptId(), params.getUrl());
         scriptIds.put(params.getUrl(), params.getScriptId());
-        for (JavaScriptDebuggerListener listener : listeners) {
+        for (JavaScriptDebuggerListener listener : getListeners()) {
             listener.scriptAdded(params.getUrl());
         }
     }
@@ -113,7 +120,7 @@ public class ChromeRDPDebugger implements JavaScriptDebugger, ChromeRDPExchangeC
 
     @Override
     public void addListener(JavaScriptDebuggerListener listener) {
-        listeners.add(listener);
+        listeners.put(listener, dummy);
     }
 
     @Override
@@ -194,23 +201,32 @@ public class ChromeRDPDebugger implements JavaScriptDebugger, ChromeRDPExchangeC
         return exchange != null;
     }
 
+    @Override
+    public void detach() {
+        if (exchange != null) {
+            exchange.disconnect();
+        }
+    }
+
     @Override
     public JavaScriptCallFrame[] getCallStack() {
         if (exchange == null) {
             return null;
         }
+        JavaScriptCallFrame[] callStack = this.callStack;
         return callStack != null ? callStack.clone() : null;
     }
 
     @Override
     public JavaScriptBreakpoint createBreakpoint(JavaScriptLocation location) {
         RDPBreakpoint breakpoint = new RDPBreakpoint(this, location);
-        breakpoints.add(breakpoint);
+        breakpoints.put(breakpoint, dummy);
         updateBreakpoint(breakpoint);
         return breakpoint;
     }
 
     void destroyBreakpoint(RDPBreakpoint breakpoint) {
+        breakpoints.remove(breakpoint);
         if (breakpoint.chromeId != null) {
             Message message = new Message();
             message.setMethod("Debugger.removeBreakpoint");
@@ -222,7 +238,7 @@ public class ChromeRDPDebugger implements JavaScriptDebugger, ChromeRDPExchangeC
     }
 
     void fireScriptAdded(String script) {
-        for (JavaScriptDebuggerListener listener : listeners) {
+        for (JavaScriptDebuggerListener listener : getListeners()) {
             listener.scriptAdded(script);
         }
     }
@@ -232,7 +248,7 @@ public class ChromeRDPDebugger implements JavaScriptDebugger, ChromeRDPExchangeC
             return;
         }
         Message message = new Message();
-        message.setId(++messageIdGenerator);
+        message.setId(messageIdGenerator.incrementAndGet());
         message.setMethod("Debugger.setBreakpoint");
         SetBreakpointCommand params = new SetBreakpointCommand();
         params.setLocation(unmap(breakpoint.getLocation()));
@@ -241,7 +257,7 @@ public class ChromeRDPDebugger implements JavaScriptDebugger, ChromeRDPExchangeC
             @Override public void received(JsonNode node) throws IOException {
                 SetBreakpointResponse response = mapper.reader(SetBreakpointResponse.class).readValue(node);
                 breakpoint.chromeId = response.getBreakpointId();
-                for (JavaScriptDebuggerListener listener : listeners) {
+                for (JavaScriptDebuggerListener listener : getListeners()) {
                     listener.breakpointChanged(breakpoint);
                 }
             }

teavm-chrome-rdp/src/main/java/org/teavm/chromerdp/ChromeRDPDebuggerEndpoint.java

@@ -52,6 +52,15 @@ public class ChromeRDPDebuggerEndpoint implements ChromeRDPExchange {
         }
     }
 
+    @Override
+    public void disconnect() {
+        try {
+            session.close();
+        } catch (IOException e) {
+            throw new RuntimeException(e);
+        }
+    }
+
     @OnMessage
     public void receive(String message) throws IOException {
         for (ChromeRDPExchangeListener listener : listeners) {

teavm-chrome-rdp/src/main/java/org/teavm/chromerdp/ChromeRDPExchange.java

@@ -7,6 +7,8 @@ package org.teavm.chromerdp;
 public interface ChromeRDPExchange {
     void send(String message);
 
+    void disconnect();
+
     void addListener(ChromeRDPExchangeListener listener);
 
     void removeListener(ChromeRDPExchangeListener listener);

teavm-chrome-rdp/src/main/java/org/teavm/chromerdp/RDPBreakpoint.java

@@ -48,6 +48,6 @@ public class RDPBreakpoint implements JavaScriptBreakpoint {
 
     @Override
     public boolean isValid() {
-        return chromeId != null;
+        return chromeId != null && debugger != null && debugger.isAttached();
     }
 }

teavm-core/src/main/java/org/teavm/debugging/Breakpoint.java

@@ -24,7 +24,7 @@ import java.util.List;
  */
 public class Breakpoint {
     private Debugger debugger;
-    List<JavaScriptBreakpoint> jsBreakpoints = new ArrayList<>();
+    volatile List<JavaScriptBreakpoint> jsBreakpoints = new ArrayList<>();
     private SourceLocation location;
     boolean valid;
 

teavm-core/src/main/java/org/teavm/debugging/Debugger.java

@@ -16,6 +16,10 @@
 package org.teavm.debugging;
 
 import java.util.*;
+import java.util.concurrent.BlockingQueue;
+import java.util.concurrent.ConcurrentHashMap;
+import java.util.concurrent.ConcurrentMap;
+import java.util.concurrent.LinkedBlockingQueue;
 import org.teavm.model.MethodReference;
 
 /**
@@ -25,16 +29,18 @@ import org.teavm.model.MethodReference;
 // TODO: variable name handling
 // TODO: class fields handling
 public class Debugger {
-    private List<DebuggerListener> listeners = new ArrayList<>();
+    private static final Object dummyObject = new Object();
+    private ConcurrentMap<DebuggerListener, Object> listeners = new ConcurrentHashMap<>();
     private JavaScriptDebugger javaScriptDebugger;
     private DebugInformationProvider debugInformationProvider;
-    private List<JavaScriptBreakpoint> temporaryJsBreakpoints = new ArrayList<>();
+    private BlockingQueue<JavaScriptBreakpoint> temporaryBreakpoints = new LinkedBlockingQueue<>();
-    private Map<String, DebugInformation> debugInformationMap = new HashMap<>();
+    private ConcurrentMap<String, DebugInformation> debugInformationMap = new ConcurrentHashMap<>();
-    private Map<String, List<DebugInformation>> debugInformationFileMap = new HashMap<>();
+    private ConcurrentMap<String, ConcurrentMap<DebugInformation, Object>> debugInformationFileMap =
-    private Map<DebugInformation, String> scriptMap = new HashMap<>();
+            new ConcurrentHashMap<>();
-    Map<JavaScriptBreakpoint, Breakpoint> breakpointMap = new HashMap<>();
+    private ConcurrentMap<DebugInformation, String> scriptMap = new ConcurrentHashMap<>();
-    Set<Breakpoint> breakpoints = new HashSet<>();
+    ConcurrentMap<JavaScriptBreakpoint, Breakpoint> breakpointMap = new ConcurrentHashMap<>();
-    private CallFrame[] callStack;
+    ConcurrentMap<Breakpoint, Object> breakpoints = new ConcurrentHashMap<>();
+    private volatile CallFrame[] callStack;
 
     public Debugger(JavaScriptDebugger javaScriptDebugger, DebugInformationProvider debugInformationProvider) {
         this.javaScriptDebugger = javaScriptDebugger;
@@ -43,36 +49,36 @@ public class Debugger {
     }
 
     public void addListener(DebuggerListener listener) {
-        listeners.add(listener);
+        listeners.put(listener, dummyObject);
     }
 
     public void removeListener(DebuggerListener listener) {
         listeners.remove(listener);
     }
 
-    public void suspend() {
+    public synchronized void suspend() {
         javaScriptDebugger.suspend();
     }
 
-    public void resume() {
+    public synchronized void resume() {
         javaScriptDebugger.resume();
     }
 
-    public void stepInto() {
+    public synchronized void stepInto() {
         javaScriptDebugger.stepInto();
     }
 
-    public void stepOut() {
+    public synchronized void stepOut() {
         javaScriptDebugger.stepOut();
     }
 
-    public void stepOver() {
+    public synchronized void stepOver() {
         javaScriptDebugger.stepOver();
     }
 
     private List<DebugInformation> debugInformationBySource(String sourceFile) {
-        List<DebugInformation> list = debugInformationFileMap.get(sourceFile);
+        Map<DebugInformation, Object> list = debugInformationFileMap.get(sourceFile);
-        return list != null ? list : Collections.<DebugInformation>emptyList();
+        return list != null ? new ArrayList<>(list.keySet()) : Collections.<DebugInformation>emptyList();
     }
 
     public void continueToLocation(SourceLocation location) {
@@ -90,7 +96,7 @@ public class Debugger {
                         location.getLine(), location.getColumn());
                 JavaScriptBreakpoint jsBreakpoint = javaScriptDebugger.createBreakpoint(jsLocation);
                 if (jsBreakpoint != null) {
-                    temporaryJsBreakpoints.add(jsBreakpoint);
+                    temporaryBreakpoints.add(jsBreakpoint);
                 }
             }
         }
@@ -107,14 +113,14 @@ public class Debugger {
 
     public Breakpoint createBreakpoint(SourceLocation location) {
         Breakpoint breakpoint = new Breakpoint(this, location);
-        breakpoints.add(breakpoint);
+        breakpoints.put(breakpoint, dummyObject);
         updateInternalBreakpoints(breakpoint);
         updateBreakpointStatus(breakpoint, false);
         return breakpoint;
     }
 
     public Set<Breakpoint> getBreakpoints() {
-        return new HashSet<>(breakpoints);
+        return new HashSet<>(breakpoints.keySet());
     }
 
     void updateInternalBreakpoints(Breakpoint breakpoint) {
@@ -122,7 +128,7 @@ public class Debugger {
             breakpointMap.remove(jsBreakpoint);
             jsBreakpoint.destroy();
         }
-        breakpoint.jsBreakpoints.clear();
+        List<JavaScriptBreakpoint> jsBreakpoints = new ArrayList<>();
         SourceLocation location = breakpoint.getLocation();
         for (DebugInformation debugInformation : debugInformationBySource(location.getFileName())) {
             Collection<GeneratedLocation> locations = debugInformation.getGeneratedLocations(location);
@@ -130,10 +136,15 @@ public class Debugger {
                 JavaScriptLocation jsLocation = new JavaScriptLocation(scriptMap.get(debugInformation),
                         genLocation.getLine(), genLocation.getColumn());
                 JavaScriptBreakpoint jsBreakpoint = javaScriptDebugger.createBreakpoint(jsLocation);
-                breakpoint.jsBreakpoints.add(jsBreakpoint);
+                jsBreakpoints.add(jsBreakpoint);
                 breakpointMap.put(jsBreakpoint, breakpoint);
             }
         }
+        breakpoint.jsBreakpoints = jsBreakpoints;
+    }
+
+    private DebuggerListener[] getListeners() {
+        return listeners.keySet().toArray(new DebuggerListener[0]);
     }
 
     void updateBreakpointStatus(Breakpoint breakpoint, boolean fireEvent) {
@@ -146,7 +157,7 @@ public class Debugger {
         if (breakpoint.valid != valid) {
             breakpoint.valid = valid;
             if (fireEvent) {
-                for (DebuggerListener listener : listeners) {
+                for (DebuggerListener listener : getListeners()) {
                     listener.breakpointStatusChanged(breakpoint);
                 }
             }
@@ -192,17 +203,23 @@ public class Debugger {
         if (debugInfo == null) {
             return;
         }
-        debugInformationMap.put(name, debugInfo);
+        if (debugInformationMap.putIfAbsent(name, debugInfo) != null) {
+            return;
+        }
         for (String sourceFile : debugInfo.getCoveredSourceFiles()) {
-            List<DebugInformation> list = debugInformationFileMap.get(sourceFile);
+            ConcurrentMap<DebugInformation, Object> list = debugInformationFileMap.get(sourceFile);
             if (list == null) {
-                list = new ArrayList<>();
+                list = new ConcurrentHashMap<>();
-                debugInformationFileMap.put(sourceFile, list);
+                ConcurrentMap<DebugInformation, Object> existing = debugInformationFileMap.putIfAbsent(
+                        sourceFile, list);
+                if (existing != null) {
+                    list = existing;
+                }
             }
-            list.add(debugInfo);
+            list.put(debugInfo, dummyObject);
         }
         scriptMap.put(debugInfo, name);
-        for (Breakpoint breakpoint : breakpoints) {
+        for (Breakpoint breakpoint : breakpoints.keySet()) {
             updateInternalBreakpoints(breakpoint);
             updateBreakpointStatus(breakpoint, true);
         }
@@ -212,40 +229,45 @@ public class Debugger {
         return javaScriptDebugger.isAttached();
     }
 
+    public void detach() {
+        javaScriptDebugger.detach();
+    }
+
     void destroyBreakpoint(Breakpoint breakpoint) {
         for (JavaScriptBreakpoint jsBreakpoint : breakpoint.jsBreakpoints) {
             jsBreakpoint.destroy();
             breakpointMap.remove(jsBreakpoint);
         }
-        breakpoint.jsBreakpoints.clear();
+        breakpoint.jsBreakpoints = new ArrayList<>();
         breakpoints.remove(this);
     }
 
     private void fireResumed() {
-        for (JavaScriptBreakpoint jsBreakpoint : temporaryJsBreakpoints) {
+        List<JavaScriptBreakpoint> termporaryBreakpoints = new ArrayList<>();
+        this.temporaryBreakpoints.drainTo(termporaryBreakpoints);
+        for (JavaScriptBreakpoint jsBreakpoint : temporaryBreakpoints) {
             jsBreakpoint.destroy();
         }
-        temporaryJsBreakpoints.clear();
+        for (DebuggerListener listener : getListeners()) {
-        for (DebuggerListener listener : listeners) {
             listener.resumed();
         }
     }
 
     private void fireAttached() {
-        for (Breakpoint breakpoint : breakpoints) {
+        for (Breakpoint breakpoint : breakpoints.keySet()) {
             updateInternalBreakpoints(breakpoint);
             updateBreakpointStatus(breakpoint, false);
         }
-        for (DebuggerListener listener : listeners) {
+        for (DebuggerListener listener : getListeners()) {
             listener.attached();
         }
     }
 
     private void fireDetached() {
-        for (Breakpoint breakpoint : breakpoints) {
+        for (Breakpoint breakpoint : breakpoints.keySet()) {
             updateBreakpointStatus(breakpoint, false);
         }
-        for (DebuggerListener listener : listeners) {
+        for (DebuggerListener listener : getListeners()) {
             listener.detached();
         }
     }
@@ -266,7 +288,7 @@ public class Debugger {
         @Override
         public void paused() {
             callStack = null;
-            for (DebuggerListener listener : listeners) {
+            for (DebuggerListener listener : getListeners()) {
                 listener.paused();
             }
         }

teavm-core/src/main/java/org/teavm/debugging/JavaScriptDebugger.java

@@ -40,6 +40,8 @@ public interface JavaScriptDebugger {
 
     boolean isAttached();
 
+    void detach();
+
     JavaScriptCallFrame[] getCallStack();
 
     JavaScriptBreakpoint createBreakpoint(JavaScriptLocation location);

teavm-eclipse-plugin/src/main/java/org/teavm/eclipse/debugger/TeaVMDebugTarget.java

@@ -14,6 +14,7 @@ import org.teavm.chromerdp.ChromeRDPServer;
 import org.teavm.debugging.Breakpoint;
 import org.teavm.debugging.Debugger;
 import org.teavm.debugging.DebuggerListener;
+import org.teavm.debugging.JavaScriptDebugger;
 
 /**
  *
@@ -23,6 +24,7 @@ import org.teavm.debugging.DebuggerListener;
 public class TeaVMDebugTarget implements IDebugTarget, IStep {
     ILaunch launch;
     Debugger teavmDebugger;
+    JavaScriptDebugger jsDebugger;
     private ChromeRDPServer server;
     private boolean terminated;
     private TeaVMDebugProcess process;
@@ -90,6 +92,7 @@ public class TeaVMDebugTarget implements IDebugTarget, IStep {
         terminated = true;
         server.stop();
         fireEvent(new DebugEvent(this, DebugEvent.TERMINATE));
+        fireEvent(new DebugEvent(thread, DebugEvent.TERMINATE));
     }
 
     @Override
@@ -187,6 +190,7 @@ public class TeaVMDebugTarget implements IDebugTarget, IStep {
 
     @Override
     public void disconnect() throws DebugException {
+        teavmDebugger.detach();
     }
 
     @Override

teavm-eclipse-plugin/src/main/java/org/teavm/eclipse/debugger/TeaVMLaunchConfigurationDelegate.java

@@ -1,16 +1,13 @@
 package org.teavm.eclipse.debugger;
 
-import java.io.IOException;
-import java.util.ArrayList;
-import java.util.List;
 import org.eclipse.core.runtime.CoreException;
 import org.eclipse.core.runtime.IProgressMonitor;
 import org.eclipse.debug.core.ILaunch;
 import org.eclipse.debug.core.ILaunchConfiguration;
 import org.eclipse.debug.core.ILaunchManager;
 import org.eclipse.debug.core.model.ILaunchConfigurationDelegate;
-import org.eclipse.ui.PlatformUI;
+import org.teavm.chromerdp.ChromeRDPDebugger;
-import org.teavm.chromerdp.*;
+import org.teavm.chromerdp.ChromeRDPServer;
 import org.teavm.debugging.Debugger;
 import org.teavm.debugging.URLDebugInformationProvider;
 
@@ -29,64 +26,15 @@ public class TeaVMLaunchConfigurationDelegate implements ILaunchConfigurationDel
         final ChromeRDPServer server = new ChromeRDPServer();
         server.setPort(port);
         ChromeRDPDebugger jsDebugger = new ChromeRDPDebugger();
-        server.setExchangeConsumer(new SynchronousMessageExchange(jsDebugger));
+        server.setExchangeConsumer(jsDebugger);
         Debugger debugger = new Debugger(jsDebugger, new URLDebugInformationProvider(""));
         new Thread() {
             @Override public void run() {
                 server.start();
             }
         }.start();
-        launch.addDebugTarget(new TeaVMDebugTarget(launch, debugger, server));
+        TeaVMDebugTarget target = new TeaVMDebugTarget(launch, debugger, server);
-    }
+        launch.addDebugTarget(target);
-
+        launch.addProcess(target.getProcess());
-    private static class SynchronousMessageExchange implements ChromeRDPExchangeConsumer,
-            ChromeRDPExchange {
-        private List<ChromeRDPExchangeListener> listeners = new ArrayList<>();
-        private ChromeRDPDebugger debugger;
-        private ChromeRDPExchange exchange;
-
-        public SynchronousMessageExchange(ChromeRDPDebugger debugger) {
-            this.debugger = debugger;
-        }
-
-        @Override
-        public void setExchange(ChromeRDPExchange exchange) {
-            this.exchange = exchange;
-            debugger.setExchange(this);
-            exchange.addListener(new ChromeRDPExchangeListener() {
-                @Override public void received(final String message) throws IOException {
-                    postToUIThread(message);
-                }
-            });
-        }
-
-        private void postToUIThread(final String message) {
-            PlatformUI.getWorkbench().getDisplay().asyncExec(new Runnable() {
-                @Override public void run() {
-                    try {
-                        for (ChromeRDPExchangeListener listener : listeners) {
-                            listener.received(message);
-                        }
-                    } catch (IOException e) {
-                        // TODO: add logging
-                    }
-                }
-            });
-        }
-
-        @Override
-        public void send(String message) {
-            exchange.send(message);
-        }
-
-        @Override
-        public void addListener(ChromeRDPExchangeListener listener) {
-            listeners.add(listener);
-        }
-
-        @Override
-        public void removeListener(ChromeRDPExchangeListener listener) {
-            listeners.remove(listener);
-        }
     }
 }

teavm-eclipse-plugin/src/main/java/org/teavm/eclipse/debugger/TeaVMStackFrame.java

@@ -74,7 +74,7 @@ public class TeaVMStackFrame implements IStackFrame {
 
     @Override
     public boolean canResume() {
-        return false;
+        return thread.getTopStackFrame() == this;
     }
 
     @Override

teavm-eclipse-plugin/src/main/java/org/teavm/eclipse/debugger/TeaVMThread.java

@@ -29,11 +29,13 @@ public class TeaVMThread implements IThread {
             @Override
             public void resumed() {
                 updateStackTrace();
+                fireEvent(new DebugEvent(TeaVMThread.this, DebugEvent.RESUME));
             }
 
             @Override
             public void paused() {
                 updateStackTrace();
+                fireEvent(new DebugEvent(TeaVMThread.this, DebugEvent.SUSPEND));
             }
 
             @Override
@@ -70,16 +72,17 @@ public class TeaVMThread implements IThread {
 
     @Override
     public boolean canTerminate() {
-        return false;
+        return true;
     }
 
     @Override
     public boolean isTerminated() {
-        return false;
+        return debugTarget.isTerminated();
     }
 
     @Override
     public void terminate() throws DebugException {
+        debugTarget.terminate();
     }
 
     @SuppressWarnings("rawtypes")
@@ -190,6 +193,6 @@ public class TeaVMThread implements IThread {
 
     @Override
     public boolean hasStackFrames() throws DebugException {
-        return true;
+        return stackTrace != null;
     }
 }