| /******************************************************************************* |
| * Copyright (c) 2021 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 |
| * |
| * Contributors: |
| * IBM Corporation - initial API and implementation |
| *******************************************************************************/ |
| package org.eclipse.jdt.internal.compiler.ast; |
| |
| import org.eclipse.jdt.internal.compiler.ASTVisitor; |
| 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.lookup.BlockScope; |
| import org.eclipse.jdt.internal.compiler.lookup.ExtraCompilerModifiers; |
| import org.eclipse.jdt.internal.compiler.lookup.LocalVariableBinding; |
| import org.eclipse.jdt.internal.compiler.lookup.Scope; |
| import org.eclipse.jdt.internal.compiler.lookup.TypeBinding; |
| |
| public class TypePattern extends Pattern { |
| |
| public LocalDeclaration local; |
| |
| public TypePattern(LocalDeclaration local) { |
| this.local = local; |
| } |
| |
| @Override |
| public void collectPatternVariablesToScope(LocalVariableBinding[] variables, BlockScope scope) { |
| if (this.resolvedType == null) { |
| this.resolveType(scope); |
| } |
| if (this.local != null && this.local.binding != null) { |
| if (this.patternVarsWhenTrue == null) { |
| this.patternVarsWhenTrue = new LocalVariableBinding[1]; |
| this.patternVarsWhenTrue[0] = this.local.binding; |
| } else { |
| this.addPatternVariablesWhenTrue(new LocalVariableBinding[] {this.local.binding}); |
| } |
| } |
| } |
| @Override |
| public boolean checkUnsafeCast(Scope scope, TypeBinding castType, TypeBinding expressionType, TypeBinding match, boolean isNarrowing) { |
| if (!castType.isReifiable()) |
| return CastExpression.checkUnsafeCast(this, scope, castType, expressionType, match, isNarrowing); |
| else |
| return super.checkUnsafeCast(scope, castType, expressionType, match, isNarrowing); |
| } |
| |
| @Override |
| public FlowInfo analyseCode(BlockScope currentScope, FlowContext flowContext, FlowInfo flowInfo) { |
| flowInfo.markAsDefinitelyAssigned(this.local.binding); |
| if (!this.isTotalTypeNode) { |
| // non-total type patterns create a nonnull local: |
| flowInfo.markAsDefinitelyNonNull(this.local.binding); |
| } else { |
| // total type patterns inherit the nullness of the value being switched over, unless ... |
| if (flowContext.associatedNode instanceof SwitchStatement) { |
| SwitchStatement swStmt = (SwitchStatement) flowContext.associatedNode; |
| int nullStatus = swStmt.containsNull |
| ? FlowInfo.NON_NULL // ... null is handled in a separate case |
| : swStmt.expression.nullStatus(flowInfo, flowContext); |
| flowInfo.markNullStatus(this.local.binding, nullStatus); |
| } |
| } |
| return flowInfo; |
| } |
| |
| @Override |
| public void generateCode(BlockScope currentScope, CodeStream codeStream) { |
| if (this.local != null) { |
| LocalVariableBinding localBinding = this.local.binding; |
| if (!this.isTotalTypeNode) |
| codeStream.checkcast(localBinding.type); |
| this.local.generateCode(currentScope, codeStream); |
| codeStream.store(localBinding, false); |
| localBinding.recordInitializationStartPC(codeStream.position); |
| } |
| } |
| |
| @Override |
| public LocalDeclaration getPatternVariableIntroduced() { |
| return this.local; |
| } |
| |
| @Override |
| public void resolve(BlockScope scope) { |
| this.resolveType(scope); |
| } |
| @Override |
| public boolean isTotalForType(TypeBinding type) { |
| if (type == null || this.resolvedType == null) |
| return false; |
| return (type.erasure().isSubtypeOf(this.resolvedType.erasure(), false)); |
| } |
| @Override |
| public boolean dominates(Pattern p) { |
| return isTotalForType(p.resolvedType); |
| } |
| |
| /* |
| * A type pattern, p, declaring a pattern variable x of type T, that is total for U, |
| * is resolved to an any pattern that declares x of type T; |
| * otherwise it is resolved to p. |
| */ |
| @Override |
| public TypeBinding resolveAtType(BlockScope scope, TypeBinding u) { |
| if (this.resolvedType == null) { |
| this.resolvedType = this.local.binding.type; |
| } |
| return this.resolvedType; |
| } |
| |
| @Override |
| public TypeBinding resolveType(BlockScope scope) { |
| if (this.resolvedType != null || this.local == null) |
| return this.resolvedType; |
| |
| this.local.modifiers |= ExtraCompilerModifiers.AccPatternVariable; |
| this.local.resolve(scope, true); |
| if (this.local.binding != null) { |
| this.local.binding.modifiers |= ExtraCompilerModifiers.AccPatternVariable; |
| this.local.binding.useFlag = LocalVariableBinding.USED; |
| this.resolvedType = this.local.binding.type; |
| } |
| return this.resolvedType; |
| } |
| |
| @Override |
| public void traverse(ASTVisitor visitor, BlockScope scope) { |
| if (visitor.visit(this, scope)) { |
| if (this.local != null) |
| this.local.traverse(visitor, scope); |
| } |
| visitor.endVisit(this, scope); |
| } |
| |
| @Override |
| public StringBuffer printExpression(int indent, StringBuffer output) { |
| return this.local != null ? this.local.printAsExpression(indent, output) : output; |
| } |
| } |