Java Code Examples for org.eclipse.xtext.xbase.XCasePart#getCase()

@Check
public void checkTypeGuardsOrder(XSwitchExpression expression) {
	if (isIgnored(IssueCodes.UNREACHABLE_CASE)) {
		return;
	}
	ITypeReferenceOwner owner = new StandardTypeReferenceOwner(getServices(), expression);
	List<LightweightTypeReference> previousTypeReferences = new ArrayList<LightweightTypeReference>();
	for (XCasePart casePart : expression.getCases()) {
		JvmTypeReference typeGuard = casePart.getTypeGuard();
		if (typeGuard == null) {
			continue;
		}
		LightweightTypeReference actualType = owner.toLightweightTypeReference(typeGuard);
		if (actualType == null) {
			continue;
		}
		if (isHandled(actualType, previousTypeReferences)) {
			addIssue("Unreachable code: The case can never match. It is already handled by a previous condition.", typeGuard, IssueCodes.UNREACHABLE_CASE);
			continue;
		}
		if (casePart.getCase() == null) {
			previousTypeReferences.add(actualType);
		}
	}
}
 

@Check
public void checkTypeGuardsOrderWithGenerics(XSwitchExpression expression) {
	if (isIgnored(IssueCodes.UNREACHABLE_CASE)) {
		return;
	}
	ITypeReferenceOwner owner = new StandardTypeReferenceOwner(getServices(), expression);
	List<LightweightTypeReference> previousTypeReferences = new ArrayList<LightweightTypeReference>();
	for (XCasePart casePart : expression.getCases()) {
		JvmTypeReference typeGuard = casePart.getTypeGuard();
		if (typeGuard == null) {
			continue;
		}
		LightweightTypeReference typeReference = owner.toLightweightTypeReference(typeGuard);
		LightweightTypeReference actualType = typeReference.getRawTypeReference();
		if (actualType == null || typeReference == actualType) {
			continue;
		}
		if (isHandled(actualType, previousTypeReferences)) {
			addIssue("Unreachable code: The case can never match. It is already handled by a previous condition (with the same type erasure).", typeGuard, IssueCodes.UNREACHABLE_CASE);
			continue;
		}
		if (casePart.getCase() == null) {
			previousTypeReferences.add(actualType);
		}
	}
}
 

public boolean isJavaCaseExpression(XSwitchExpression it, XCasePart casePart) {
	if (casePart.getTypeGuard() != null) {
		return false;
	}
	XExpression caseExpression = casePart.getCase();
	if (caseExpression == null) {
		return false;
	}
	IResolvedTypes resolvedTypes = batchTypeResolver.resolveTypes(it);
	LightweightTypeReference caseType = resolvedTypes.getActualType(caseExpression);
	if (caseType == null) {
		return false;
	}
	LightweightTypeReference switchType = getSwitchVariableType(it);
	if (!switchType.isAssignableFrom(caseType)) {
		return false;
	}
	return true;
}
 

protected ITreeAppendable appendCloseIfStatement(XCasePart casePart, ITreeAppendable caseAppendable, XSwitchExpressionCompilationState state) {
	// close surrounding if statements
	if (state.caseNeedsIfNotMatchedCheck()) {
		if (casePart.getCase() != null) {
			caseAppendable.decreaseIndentation().newLine().append("}");
		}
		
		if (casePart.getTypeGuard() != null) {
			caseAppendable.decreaseIndentation().newLine().append("}");
			caseAppendable.closeScope();
		}
	} else if (casePart.getCase() != null && casePart.getTypeGuard() != null) {
		caseAppendable.decreaseIndentation().newLine().append("}");
		caseAppendable.closeScope();
	} else if (casePart.getTypeGuard() != null) {
		caseAppendable.closeScope();
	}
	state.finishProcessingCase();
	return caseAppendable;
}
 

@Check
public void checkDeadCode(XSwitchExpression switchExpression) {
	List<XCasePart> cases = switchExpression.getCases();
	for(int i = 0, size = cases.size(); i < size; i++) {
		XCasePart casePart = cases.get(i);
		XExpression caseExpression = casePart.getCase();
		if (!earlyExitComputer.isEarlyExit(caseExpression)) {
			validateCondition(caseExpression, false);
		} else if (!markAsDeadCode(casePart.getThen())) {
			if (casePart.getTypeGuard() == null) { 
				i = markAsDeadCode(cases, casePart, i, size);
			}
		}
	}
}
 

public boolean isConstant(XCasePart casePart) {
	XExpression caseExpression = casePart.getCase();
	if (caseExpression == null) {
		return false;
	}
	try {
		switchConstantExpressionsInterpreter.evaluate(caseExpression);
		return true;
	} catch (ConstantExpressionEvaluationException e) {
		return false;
	}
}
 

protected ITreeAppendable appendOpenIfStatement(XCasePart casePart, ITreeAppendable b, String matchedVariable, String variableName, XSwitchExpressionCompilationState state) {
	ITreeAppendable caseAppendable = b.trace(casePart, true);
	if (state.caseNeedsIfNotMatchedCheck()) {
		caseAppendable.newLine().append("if (!").append(matchedVariable).append(") {");
		caseAppendable.increaseIndentation();
	}
	JvmTypeReference typeGuard = casePart.getTypeGuard();
	if (typeGuard != null) {
		ITreeAppendable typeGuardAppendable = caseAppendable.trace(typeGuard, true);
		typeGuardAppendable.newLine().append("if (");
		if (typeGuard instanceof JvmSynonymTypeReference) {
			Iterator<JvmTypeReference> iter = ((JvmSynonymTypeReference) typeGuard).getReferences().iterator();
			while(iter.hasNext()) {
				typeGuardAppendable.append(variableName);
				typeGuardAppendable.append(" instanceof ");
				typeGuardAppendable.trace(typeGuard).append(iter.next().getType());
				if (iter.hasNext()) {
					typeGuardAppendable.append(" || ");
				}
			}
		} else {
			typeGuardAppendable.append(variableName);
			typeGuardAppendable.append(" instanceof ");
			typeGuardAppendable.trace(typeGuard).append(typeGuard.getType());
		}
		typeGuardAppendable.append(") {");
		typeGuardAppendable.increaseIndentation();
		typeGuardAppendable.openPseudoScope();
	}
	if (casePart.getCase() != null) {
		ITreeAppendable conditionAppendable = caseAppendable.trace(casePart.getCase(), true);
		internalToJavaStatement(casePart.getCase(), conditionAppendable, true);
		conditionAppendable.newLine().append("if (");
		LightweightTypeReference convertedType = getLightweightType(casePart.getCase());
		if (convertedType.isType(Boolean.TYPE) || convertedType.isType(Boolean.class)) {
			internalToJavaExpression(casePart.getCase(), conditionAppendable);
		} else {
			JvmType objectsType = findKnownType(Objects.class, casePart);
			if (objectsType != null) {
				conditionAppendable.append(objectsType);
				conditionAppendable.append(".equal(").append(variableName).append(", ");
				internalToJavaExpression(casePart.getCase(), conditionAppendable);
				conditionAppendable.append(")");
			} else {
				// use ObjectExtensions rather than a == b || a != null && a.equals(b) since
				// that won't work with primitive types and other incompatible conditional operands
				conditionAppendable.append(ObjectExtensions.class);
				conditionAppendable.append(".operator_equals(").append(variableName).append(", ");
				internalToJavaExpression(casePart.getCase(), conditionAppendable);
				conditionAppendable.append(")");
			}
		}
		conditionAppendable.append(")");
		caseAppendable.append(" {");
		caseAppendable.increaseIndentation();
	}
	// set matched to true
	return caseAppendable.newLine().append(matchedVariable).append("=true;");
}