JetBrains/intellij-community · error · SliceFilterParseException

slice.filter.parse.error.incorrect.expression

slice.filter.parse.error.incorrect.expression

Error message

Incorrect expression: {0}

What it means

Thrown by JavaSliceProvider.parseFilter when the filter text cannot be parsed into a Java expression. After the 'null'/enum branches fail to match, the parser calls JavaPsiFacade.getElementFactory().createExpressionFromText(filter, expression); if that raises IncorrectOperationException (the text is not syntactically valid Java), it is wrapped in SliceFilterParseException.

Source

Thrown at java/java-impl/src/com/intellij/slicer/JavaSliceProvider.java:162

          break;
        }
      }
    }
    PsiClass psiClass = PsiUtil.resolveClassInClassTypeOnly(type);
    if (psiClass != null && psiClass.isEnum()) {
      PsiField enumConstant = psiClass.findFieldByName(filter, false);
      if (enumConstant instanceof PsiEnumConstant) {
        return new JavaValueFilter(DfTypes.referenceConstant(enumConstant, type));
      } else {
        throw new SliceFilterParseException(JavaBundle.message("slice.filter.parse.error.enum.constant.not.found", filter));
      }
    }
    PsiExpression constant;
    try {
      constant = JavaPsiFacade.getElementFactory(expression.getProject()).createExpressionFromText(filter, expression);
    }
    catch (IncorrectOperationException ignore) {
      throw new SliceFilterParseException(JavaBundle.message("slice.filter.parse.error.incorrect.expression", filter));
    }
    PsiType constantType = constant.getType();
    if (constantType == null || !type.isAssignableFrom(constantType)) {
      throw new SliceFilterParseException(JavaBundle.message("slice.filter.parse.error.incorrect.constant.type", type.getPresentableText()));
    }
    Object o = ExpressionUtils.computeConstantExpression(constant);
    if (o == null) {
      throw new SliceFilterParseException(JavaBundle.message("slice.filter.parse.error.expression.must.evaluate.to.constant", filter));
    }
    if (relationType != RelationType.EQ) {
      if (!(o instanceof Number)) {
        throw new SliceFilterParseException(JavaBundle.message("slice.filter.parse.error.incorrect.constant.expected.number", filter));
      }
      if (PsiTypes.longType().equals(type)) {
        LongRangeSet rangeSet = LongRangeSet.point(((Number)o).longValue()).fromRelation(relationType);
        return new JavaValueFilter(DfTypes.longRange(rangeSet));
      }
      LongRangeSet rangeSet = LongRangeSet.point(((Number)o).intValue()).fromRelation(relationType);

View on GitHub (pinned to be881553f2)

Solutions

  1. Correct the filter so it is a syntactically valid Java expression (literal, constant reference, or simple expression).
  2. For string comparison use a quoted literal, e.g. "\"foo\"" in the filter field.
  3. Verify balanced parentheses/quotes and remove stray characters.
  4. Remember the expression is parsed in the context of the sliced element, so only context-free constant expressions make sense.

Example fix

// before:
filter = "foo'"

// after:
filter = "\"foo\""
Defensive patterns

Strategy: try-catch

Validate before calling

try {
  JavaPsiFacade.getElementFactory(project).createExpressionFromText(filter, context);
} catch (IncorrectOperationException e) {
  // filter is not a valid Java expression — reject before slicing
}

Try / catch

try { provider.parseFilter(expression, filter); } catch (SliceFilterParseException e) { /* invalid Java expression: report and retry */ }

Prevention

When it happens

Trigger: Entering a slice filter containing a Java syntax error — unbalanced parentheses, a stray operator, a keyword like 'new' without a body, or a plain word that is neither an enum constant nor a valid expression.

Common situations: Users pasting arbitrary text into the filter field; using string literals without proper quoting; expecting SQL-like or glob syntax where a Java expression is required; partial typing while the field is validated live.

Related errors

AI-assisted analysis of JetBrains/intellij-community@be881553f2 (2026-08-14). Data as JSON: /api/errors/cefaff25cadb0247. Report an issue: GitHub.