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/*******************************************************************************
* Copyright (c) 2000, 2019 IBM Corporation and others.
*
* This program and the accompanying materials
* are made available under the terms of the Eclipse Public License 2.0
* which accompanies this distribution, and is available at
* https://www.eclipse.org/legal/epl-2.0/
*
* SPDX-License-Identifier: EPL-2.0
*
* This is an implementation of an early-draft specification developed under the Java
* Community Process (JCP) and is made available for testing and evaluation purposes
* only. The code is not compatible with any specification of the JCP.
*
* Contributors:
* IBM Corporation - initial API and implementation
*******************************************************************************/
package org.eclipse.jdt.internal.compiler.ast;
import java.util.ArrayList;
import java.util.List;
import org.eclipse.jdt.internal.compiler.ASTVisitor;
import org.eclipse.jdt.internal.compiler.classfmt.ClassFileConstants;
import org.eclipse.jdt.internal.compiler.codegen.BranchLabel;
import org.eclipse.jdt.internal.compiler.codegen.CodeStream;
import org.eclipse.jdt.internal.compiler.flow.FlowContext;
import org.eclipse.jdt.internal.compiler.flow.FlowInfo;
import org.eclipse.jdt.internal.compiler.impl.Constant;
import org.eclipse.jdt.internal.compiler.impl.IntConstant;
//import org.eclipse.jdt.internal.compiler.impl.IntConstant;
import org.eclipse.jdt.internal.compiler.lookup.Binding;
import org.eclipse.jdt.internal.compiler.lookup.BlockScope;
import org.eclipse.jdt.internal.compiler.lookup.FieldBinding;
import org.eclipse.jdt.internal.compiler.lookup.ReferenceBinding;
import org.eclipse.jdt.internal.compiler.lookup.TypeBinding;
public class CaseStatement extends Statement {
public Expression constantExpression;
public BranchLabel targetLabel;
public Expression[] constantExpressions; // case with multiple expressions
public BranchLabel[] targetLabels; // for multiple expressions
public boolean isExpr = false;
public CaseStatement(Expression constantExpression, int sourceEnd, int sourceStart) {
this.constantExpression = constantExpression;
this.sourceEnd = sourceEnd;
this.sourceStart = sourceStart;
}
@Override
public FlowInfo analyseCode(
BlockScope currentScope,
FlowContext flowContext,
FlowInfo flowInfo) {
if (this.constantExpressions != null && this.constantExpressions.length > 1) {
for (Expression e : this.constantExpressions) {
if (e.constant == Constant.NotAConstant
&& !e.resolvedType.isEnum()) {
currentScope.problemReporter().caseExpressionMustBeConstant(e);
}
this.constantExpression.analyseCode(currentScope, flowContext, flowInfo);
}
} else {
if (this.constantExpression != null) {
if (this.constantExpression.constant == Constant.NotAConstant
&& !this.constantExpression.resolvedType.isEnum()) {
currentScope.problemReporter().caseExpressionMustBeConstant(this.constantExpression);
}
this.constantExpression.analyseCode(currentScope, flowContext, flowInfo);
}
}
return flowInfo;
}
@Override
public StringBuffer printStatement(int tab, StringBuffer output) {
printIndent(tab, output);
if (this.constantExpression == null) {
output.append("default "); //$NON-NLS-1$
output.append(this.isExpr ? "->" : ":"); //$NON-NLS-1$ //$NON-NLS-2$
} else {
output.append("case "); //$NON-NLS-1$
if (this.constantExpressions != null && this.constantExpressions.length > 0) {
for (int i = 0, l = this.constantExpressions.length; i < l; ++i) {
this.constantExpressions[i].printExpression(0, output);
if (i < l -1) output.append(',');
}
} else {
this.constantExpression.printExpression(0, output);
}
output.append(this.isExpr ? " ->" : " :"); //$NON-NLS-1$ //$NON-NLS-2$
}
return output;
}
/**
* Case code generation
*
*/
@Override
public void generateCode(BlockScope currentScope, CodeStream codeStream) {
if ((this.bits & ASTNode.IsReachable) == 0) {
return;
}
int pc = codeStream.position;
if (this.targetLabels != null) {
for (int i = 0, l = this.targetLabels.length; i < l; ++i) {
this.targetLabels[i].place();
}
} else {
this.targetLabel.place();
}
codeStream.recordPositionsFrom(pc, this.sourceStart);
}
/**
* No-op : should use resolveCase(...) instead.
*/
@Override
public void resolve(BlockScope scope) {
// no-op : should use resolveCase(...) instead.
}
/**
* Returns the constant intValue or ordinal for enum constants. If constant is NotAConstant, then answers Float.MIN_VALUE
* see org.eclipse.jdt.internal.compiler.ast.Statement#resolveCase(org.eclipse.jdt.internal.compiler.lookup.BlockScope, org.eclipse.jdt.internal.compiler.lookup.TypeBinding, org.eclipse.jdt.internal.compiler.ast.SwitchStatement)
*/
@Override
public Constant[] resolveCase(BlockScope scope, TypeBinding switchExpressionType, SwitchStatement switchStatement) {
// switchExpressionType maybe null in error case
scope.enclosingCase = this; // record entering in a switch case block
if (this.constantExpression == null) {
// remember the default case into the associated switch statement
if (switchStatement.defaultCase != null)
scope.problemReporter().duplicateDefaultCase(this);
// on error the last default will be the selected one ...
switchStatement.defaultCase = this;
return Constant.NotAConstantList;
}
// add into the collection of cases of the associated switch statement
switchStatement.cases[switchStatement.caseCount++] = this;
if (switchExpressionType != null && switchExpressionType.isEnum() && (this.constantExpression instanceof SingleNameReference)) {
((SingleNameReference) this.constantExpression).setActualReceiverType((ReferenceBinding)switchExpressionType);
}
TypeBinding caseType = this.constantExpression.resolveType(scope);
if (caseType == null || switchExpressionType == null) return Constant.NotAConstantList;
// tag constant name with enum type for privileged access to its members
if (this.constantExpressions != null && this.constantExpressions.length > 1) {
List<Constant> cases = new ArrayList<>();
for (Expression e : this.constantExpressions) {
if (e != this.constantExpression) {
if (switchExpressionType.isEnum() && (e instanceof SingleNameReference)) {
((SingleNameReference) e).setActualReceiverType((ReferenceBinding)switchExpressionType);
}
e.resolveType(scope);
}
Constant con = resolveConstantExpression(scope, caseType, switchExpressionType, switchStatement, e);
if (con != Constant.NotAConstant) {
cases.add(con);
}
}
if (cases.size() > 0) {
return cases.toArray(new Constant[cases.size()]);
}
} else {
return new Constant[] { resolveConstantExpression(scope, caseType, switchExpressionType, switchStatement, this.constantExpression) };
}
return Constant.NotAConstantList;
}
public Constant resolveConstantExpression(BlockScope scope,
TypeBinding caseType,
TypeBinding switchExpressionType,
SwitchStatement switchStatement,
Expression expression) {
if (expression.isConstantValueOfTypeAssignableToType(caseType, switchExpressionType)
|| caseType.isCompatibleWith(switchExpressionType)) {
if (caseType.isEnum()) {
if (((expression.bits & ASTNode.ParenthesizedMASK) >> ASTNode.ParenthesizedSHIFT) != 0) {
scope.problemReporter().enumConstantsCannotBeSurroundedByParenthesis(expression);
}
if (expression instanceof NameReference
&& (expression.bits & ASTNode.RestrictiveFlagMASK) == Binding.FIELD) {
NameReference reference = (NameReference) expression;
FieldBinding field = reference.fieldBinding();
if ((field.modifiers & ClassFileConstants.AccEnum) == 0) {
scope.problemReporter().enumSwitchCannotTargetField(reference, field);
} else if (reference instanceof QualifiedNameReference) {
scope.problemReporter().cannotUseQualifiedEnumConstantInCaseLabel(reference, field);
}
return IntConstant.fromValue(field.original().id + 1); // (ordinal value + 1) zero should not be returned see bug 141810
}
} else {
return expression.constant;
}
} else if (isBoxingCompatible(caseType, switchExpressionType, expression, scope)) {
// constantExpression.computeConversion(scope, caseType, switchExpressionType); - do not report boxing/unboxing conversion
return expression.constant;
}
scope.problemReporter().typeMismatchError(caseType, switchExpressionType, this.constantExpression, switchStatement.expression);
return Constant.NotAConstant;
}
@Override
public void traverse(ASTVisitor visitor, BlockScope blockScope) {
if (visitor.visit(this, blockScope)) {
if (this.constantExpressions != null && this.constantExpressions.length > 1) {
for (Expression e : this.constantExpressions) {
e.traverse(visitor, blockScope);
}
} else {
if (this.constantExpression != null) this.constantExpression.traverse(visitor, blockScope);
}
}
visitor.endVisit(this, blockScope);
}
}
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