com.github.javaparser.ast.expr.InstanceOfExpr Maven / Gradle / Ivy
/*
* Copyright (C) 2007-2010 Júlio Vilmar Gesser.
* Copyright (C) 2011, 2013-2023 The JavaParser Team.
*
* This file is part of JavaParser.
*
* JavaParser can be used either under the terms of
* a) the GNU Lesser General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
* b) the terms of the Apache License
*
* You should have received a copy of both licenses in LICENCE.LGPL and
* LICENCE.APACHE. Please refer to those files for details.
*
* JavaParser is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU Lesser General Public License for more details.
*/
package com.github.javaparser.ast.expr;
import com.github.javaparser.TokenRange;
import com.github.javaparser.ast.AllFieldsConstructor;
import com.github.javaparser.ast.Generated;
import com.github.javaparser.ast.Node;
import com.github.javaparser.ast.nodeTypes.NodeWithExpression;
import com.github.javaparser.ast.nodeTypes.NodeWithType;
import com.github.javaparser.ast.observer.ObservableProperty;
import com.github.javaparser.ast.type.ClassOrInterfaceType;
import com.github.javaparser.ast.type.ReferenceType;
import com.github.javaparser.ast.visitor.CloneVisitor;
import com.github.javaparser.ast.visitor.GenericVisitor;
import com.github.javaparser.ast.visitor.VoidVisitor;
import com.github.javaparser.metamodel.InstanceOfExprMetaModel;
import com.github.javaparser.metamodel.JavaParserMetaModel;
import com.github.javaparser.metamodel.OptionalProperty;
import java.util.Optional;
import java.util.function.Consumer;
import static com.github.javaparser.utils.Utils.assertNotNull;
/**
* The instanceof statement
*
* Java ?? to 13
* The {@code instanceof} expression is a
* relational operator,
* evaluating to true if the object on the left hand side
* is an instance of the type ({@link ReferenceType}) on the right hand side.
*
*
* Example:
*
{@code tool instanceof Drill}
*
*
This is then used wherever a conditional/boolean value can be used. For example:
*
* {@code if (obj instanceof String) {
* String s = (String) obj;
* // use s
* }}
*
* Java 14
* Since JDK14, it is possible to bind a variable that is cast to the type being tested against.
* This is referred to as a {@code Pattern} within JEP305,
* and avoids the need to cast to the desired type.
*
* Example:
*
{@code tool instanceof Drill d}
*
*
This is then used wherever a conditional/boolean value can be used. The scope of the variable created can vary, and is defined further within
* JEP305.
*
* {@code if (obj instanceof String s) {
* // can use s here
* } else {
* // can't use s here
* }}
*
*
* JDK14 Grammar
* Per JEP305:
*
* {@code RelationalExpression:
* ...
* RelationalExpression instanceof ReferenceType
* RelationalExpression instanceof Pattern
*
* Pattern:
* ReferenceType Identifier}
*
* @author Julio Vilmar Gesser
*
* @see com.github.javaparser.ast.expr.PatternExpr
* @see JEP305: https://bugs.openjdk.java.net/browse/JDK-8181287
* @see https://docs.oracle.com/javase/specs/jls/se11/html/jls-15.html#jls-15.20
*/
public class InstanceOfExpr extends Expression implements NodeWithType, NodeWithExpression {
private Expression expression;
@OptionalProperty
private PatternExpr pattern;
private ReferenceType type;
public InstanceOfExpr() {
this(null, new NameExpr(), new ClassOrInterfaceType(), null);
}
public InstanceOfExpr(final Expression expression, final ReferenceType type) {
this(null, expression, type, null);
}
@AllFieldsConstructor
public InstanceOfExpr(final Expression expression, final ReferenceType type, final PatternExpr pattern) {
this(null, expression, type, pattern);
}
/**
* This constructor is used by the parser and is considered private.
*/
@Generated("com.github.javaparser.generator.core.node.MainConstructorGenerator")
public InstanceOfExpr(TokenRange tokenRange, Expression expression, ReferenceType type, PatternExpr pattern) {
super(tokenRange);
setExpression(expression);
setType(type);
setPattern(pattern);
customInitialization();
}
/**
* Helper method which, if this is an expression with a pattern, returns the identifier/name.
*
*
For example:
*
{@code obj instanceof String stringName}
*
*
In this example, {@code getName()} returns {@code stringName}
*/
public Optional getName() {
if (pattern == null) {
return Optional.empty();
}
return Optional.of(pattern.getName());
}
@Override
@Generated("com.github.javaparser.generator.core.node.AcceptGenerator")
public R accept(final GenericVisitor v, final A arg) {
return v.visit(this, arg);
}
@Override
@Generated("com.github.javaparser.generator.core.node.AcceptGenerator")
public void accept(final VoidVisitor v, final A arg) {
v.visit(this, arg);
}
@Override
@Generated("com.github.javaparser.generator.core.node.TypeCastingGenerator")
public InstanceOfExpr asInstanceOfExpr() {
return this;
}
@Override
@Generated("com.github.javaparser.generator.core.node.CloneGenerator")
public InstanceOfExpr clone() {
return (InstanceOfExpr) accept(new CloneVisitor(), null);
}
@Generated("com.github.javaparser.generator.core.node.PropertyGenerator")
public Expression getExpression() {
return expression;
}
@Override
@Generated("com.github.javaparser.generator.core.node.GetMetaModelGenerator")
public InstanceOfExprMetaModel getMetaModel() {
return JavaParserMetaModel.instanceOfExprMetaModel;
}
@Generated("com.github.javaparser.generator.core.node.PropertyGenerator")
public Optional getPattern() {
return Optional.ofNullable(pattern);
}
@Generated("com.github.javaparser.generator.core.node.PropertyGenerator")
public ReferenceType getType() {
return type;
}
@Override
@Generated("com.github.javaparser.generator.core.node.TypeCastingGenerator")
public void ifInstanceOfExpr(Consumer action) {
action.accept(this);
}
@Override
@Generated("com.github.javaparser.generator.core.node.TypeCastingGenerator")
public boolean isInstanceOfExpr() {
return true;
}
@Override
@Generated("com.github.javaparser.generator.core.node.RemoveMethodGenerator")
public boolean remove(Node node) {
if (node == null) {
return false;
}
if (pattern != null) {
if (node == pattern) {
removePattern();
return true;
}
}
return super.remove(node);
}
@Generated("com.github.javaparser.generator.core.node.RemoveMethodGenerator")
public InstanceOfExpr removePattern() {
return setPattern((PatternExpr) null);
}
@Override
@Generated("com.github.javaparser.generator.core.node.ReplaceMethodGenerator")
public boolean replace(Node node, Node replacementNode) {
if (node == null) {
return false;
}
if (node == expression) {
setExpression((Expression) replacementNode);
return true;
}
if (pattern != null) {
if (node == pattern) {
setPattern((PatternExpr) replacementNode);
return true;
}
}
if (node == type) {
setType((ReferenceType) replacementNode);
return true;
}
return super.replace(node, replacementNode);
}
@Generated("com.github.javaparser.generator.core.node.PropertyGenerator")
public InstanceOfExpr setExpression(final Expression expression) {
assertNotNull(expression);
if (expression == this.expression) {
return this;
}
notifyPropertyChange(ObservableProperty.EXPRESSION, this.expression, expression);
if (this.expression != null)
this.expression.setParentNode(null);
this.expression = expression;
setAsParentNodeOf(expression);
return this;
}
@Generated("com.github.javaparser.generator.core.node.PropertyGenerator")
public InstanceOfExpr setPattern(final PatternExpr pattern) {
if (pattern == this.pattern) {
return this;
}
notifyPropertyChange(ObservableProperty.PATTERN, this.pattern, pattern);
if (this.pattern != null)
this.pattern.setParentNode(null);
this.pattern = pattern;
setAsParentNodeOf(pattern);
return this;
}
@Generated("com.github.javaparser.generator.core.node.PropertyGenerator")
public InstanceOfExpr setType(final ReferenceType type) {
assertNotNull(type);
if (type == this.type) {
return this;
}
notifyPropertyChange(ObservableProperty.TYPE, this.type, type);
if (this.type != null)
this.type.setParentNode(null);
this.type = type;
setAsParentNodeOf(type);
return this;
}
@Override
@Generated("com.github.javaparser.generator.core.node.TypeCastingGenerator")
public Optional toInstanceOfExpr() {
return Optional.of(this);
}
}