JetBrains/intellij-community · error · EvaluateException

Invalid local variable name ''{0}''

Error message

Invalid local variable name ''{0}''

What it means

Error "Invalid local variable name ''{0}''" thrown in JetBrains/intellij-community.

Source

Thrown at java/debugger/impl/src/com/intellij/debugger/ui/impl/watch/ArgumentValueDescriptorImpl.java:74

  }

  @Override
  public String getName() {
    return myVariable.getDisplayName();
  }

  public boolean isParameter() {
    return myVariable.isParam();
  }

  @Override
  public PsiExpression getDescriptorEvaluation(DebuggerContext context) throws EvaluateException {
    PsiElementFactory elementFactory = JavaPsiFacade.getElementFactory(myProject);
    try {
      return elementFactory.createExpressionFromText(getName(), PositionUtil.getContextElement(context));
    }
    catch (IncorrectOperationException e) {
      throw new EvaluateException(JavaDebuggerBundle.message("error.invalid.local.variable.name", getName()), e);
    }
  }

  @Override
  public XValueModifier getModifier(JavaValue value) {
    return new JavaValueModifier(value) {
      @Override
      protected void setValueImpl(@NotNull XExpression expression, @NotNull XModificationCallback callback) {
        final DecompiledLocalVariable local = ArgumentValueDescriptorImpl.this.getVariable();
        if (local != null) {
          final DebuggerContextImpl debuggerContext = DebuggerManagerEx.getInstanceEx(getProject()).getContext();
          set(expression, callback, debuggerContext, new SetValueRunnable() {
            @Override
            public void setValue(EvaluationContextImpl evaluationContext, Value newValue) throws ClassNotLoadedException,
                                                                                                 InvalidTypeException,
                                                                                                 EvaluateException {
              LocalVariablesUtil.setValue(debuggerContext.getFrameProxy().getStackFrame(), local, newValue);
              update(debuggerContext);

View on GitHub (pinned to be881553f2)

Solutions

1. Use a valid Java identifier for the local variable name.
2. Avoid keywords, spaces, and characters like '-' or '.' in the variable name.

Example fix

Use 'myValue' instead of 'my-value' in the expression.

When it happens

Trigger: A watch/evaluate expression refers to a local variable name that is not a legal Java identifier.

Common situations: Typing a malformed variable reference into Evaluate Expression or Watches.

AI-assisted analysis of JetBrains/intellij-community@be881553f2 (2026-08-14). Data as JSON: /api/errors/f315aa0fd4d1ad95. Report an issue: GitHub.