fixed NPE in read only mode

java/debugger/impl/src/com/intellij/debugger/engine/requests/RequestManagerImpl.java

@@ -291,10 +291,7 @@ public class RequestManagerImpl extends DebugProcessAdapterImpl implements Reque
   public void callbackOnPrepareClasses(final ClassPrepareRequestor requestor, final SourcePosition classPosition) {
     DebuggerManagerThreadImpl.assertIsManagerThread();
 
-    if (!myDebugProcess.getVirtualMachineProxy().canBeModified()) {
-      setInvalid(requestor, "Not available in read only mode");
-      return;
-    }
+    if (checkReadOnly(requestor)) return;
 
     List<ClassPrepareRequest> prepareRequests = myDebugProcess.getPositionManager().createPrepareRequests(requestor, classPosition);
     if(prepareRequests.isEmpty()) {
@@ -313,6 +310,9 @@ public class RequestManagerImpl extends DebugProcessAdapterImpl implements Reque
   @Override
   public void callbackOnPrepareClasses(ClassPrepareRequestor requestor, String classOrPatternToBeLoaded) {
     DebuggerManagerThreadImpl.assertIsManagerThread();
+
+    if (checkReadOnly(requestor)) return;
+
     ClassPrepareRequest classPrepareRequest = createClassPrepareRequest(requestor, classOrPatternToBeLoaded);
 
     if (classPrepareRequest != null) {
@@ -415,4 +415,12 @@ public class RequestManagerImpl extends DebugProcessAdapterImpl implements Reque
   public void clearWarnings() {
     myRequestWarnings.clear();
   }
+
+  public boolean checkReadOnly(Requestor requestor) {
+    if (!myDebugProcess.getVirtualMachineProxy().canBeModified()) {
+      setInvalid(requestor, "Not available in read only mode");
+      return true;
+    }
+    return false;
+  }
 }

java/debugger/impl/src/com/intellij/debugger/ui/breakpoints/Breakpoint.java

@@ -17,6 +17,7 @@ import com.intellij.debugger.engine.events.SuspendContextCommandImpl;
 import com.intellij.debugger.impl.DebuggerUtilsEx;
 import com.intellij.debugger.jdi.StackFrameProxyImpl;
 import com.intellij.debugger.jdi.ThreadReferenceProxyImpl;
+import com.intellij.debugger.jdi.VirtualMachineProxyImpl;
 import com.intellij.debugger.requests.ClassPrepareRequestor;
 import com.intellij.debugger.requests.Requestor;
 import com.intellij.debugger.settings.DebuggerSettings;
@@ -208,12 +209,17 @@ public abstract class Breakpoint<P extends JavaBreakpointProperties> implements
    */
   protected void createOrWaitPrepare(DebugProcessImpl debugProcess, String classToBeLoaded) {
     debugProcess.getRequestsManager().callbackOnPrepareClasses(this, classToBeLoaded);
-    processClassesPrepare(debugProcess, debugProcess.getVirtualMachineProxy().classesByName(classToBeLoaded).stream());
+    VirtualMachineProxyImpl virtualMachineProxy = debugProcess.getVirtualMachineProxy();
+    if (virtualMachineProxy.canBeModified()) {
+      processClassesPrepare(debugProcess, virtualMachineProxy.classesByName(classToBeLoaded).stream());
+    }
   }
 
   protected void createOrWaitPrepare(final DebugProcessImpl debugProcess, @NotNull final SourcePosition classPosition) {
     debugProcess.getRequestsManager().callbackOnPrepareClasses(this, classPosition);
-    processClassesPrepare(debugProcess, debugProcess.getPositionManager().getAllClasses(classPosition).stream().distinct());
+    if (debugProcess.getVirtualMachineProxy().canBeModified()) {
+      processClassesPrepare(debugProcess, debugProcess.getPositionManager().getAllClasses(classPosition).stream().distinct());
+    }
   }
 
   private void processClassesPrepare(DebugProcessImpl debugProcess, Stream<ReferenceType> classes) {

java/debugger/impl/src/com/intellij/debugger/ui/breakpoints/ExceptionBreakpoint.java

@@ -125,7 +125,7 @@ public class ExceptionBreakpoint extends Breakpoint<JavaExceptionBreakpointPrope
   @Override
   public void processClassPrepare(DebugProcess process, ReferenceType refType) {
     DebugProcessImpl debugProcess = (DebugProcessImpl)process;
-    if (shouldCreateRequest(debugProcess, true)) {
+    if (shouldCreateRequest(debugProcess, true) && !debugProcess.getRequestsManager().checkReadOnly(this)) {
       // trying to create a request
       RequestManagerImpl manager = debugProcess.getRequestsManager();
       manager.enableRequest(manager.createExceptionRequest(this, refType, isNotifyCaught(), isNotifyUncaught()));