/*******************************************************************************
* Copyright (c) 2013, 2014 IBM Corporation and others.
* All rights reserved. This program and the accompanying materials
* are made available under the terms of the Eclipse Public License v1.0
* which accompanies this distribution, and is available at
* http://www.eclipse.org/legal/epl-v10.html
*
* Contributors:
* IBM Corporation - initial API and implementation
*******************************************************************************/
package org.eclipse.jdt.core.dom;
import java.util.ArrayList;
import java.util.List;
/**
* Lambda expression AST node type (added in JLS8 API).
* <pre>
* LambdaExpression:
* Identifier <b>-></b> Body
* <b>(</b> [ Identifier { <b>,</b> Identifier } ] <b>)</b> <b>-></b> Body
* <b>(</b> [ FormalParameter { <b>,</b> FormalParameter } ] <b>)</b> <b>-></b> Body
* </pre>
*
*<p>
* The first two forms use {@link VariableDeclarationFragment} for the parameter or parameters,
* while the third form uses {@link SingleVariableDeclaration}.</p>
*<p>The Body can be either a {@link Block} or an {@link Expression}.</p>
*
* @since 3.10
* @noinstantiate This class is not intended to be instantiated by clients
*/
@SuppressWarnings({"rawtypes", "unchecked"})
public class LambdaExpression extends Expression {
/**
* The "parentheses" structural property of this node type (type: {@link Boolean}).
* <p>
* Note that parentheses are required unless {@link #parameters()} contains
* just a single {@link VariableDeclarationFragment}.
* ASTRewrite may ignore this property if necessary.
* </p>
*/
public static final SimplePropertyDescriptor PARENTHESES_PROPERTY =
new SimplePropertyDescriptor(LambdaExpression.class, "parentheses", boolean.class, MANDATORY); //$NON-NLS-1$
/**
* The "parameters" structural property of this node type (element type: {@link VariableDeclaration}).
* <p>
* Note that all elements must be of the same type, either all {@link SingleVariableDeclaration} or all {@link VariableDeclarationFragment}.
* </p>
*/
public static final ChildListPropertyDescriptor PARAMETERS_PROPERTY =
new ChildListPropertyDescriptor(LambdaExpression.class, "parameters", VariableDeclaration.class, CYCLE_RISK); //$NON-NLS-1$
/**
* The "body" structural property of this node type (child type: {@link ASTNode},
* must be either a {@link Block} or an {@link Expression}).
*/
public static final ChildPropertyDescriptor BODY_PROPERTY =
new ChildPropertyDescriptor(LambdaExpression.class, "body", ASTNode.class, MANDATORY, CYCLE_RISK); //$NON-NLS-1$
/**
* A list of property descriptors (element type:
* {@link StructuralPropertyDescriptor}),
* or null if uninitialized.
*/
private static final List PROPERTY_DESCRIPTORS_8_0;
static {
List propertyList = new ArrayList(4);
createPropertyList(LambdaExpression.class, propertyList);
addProperty(PARENTHESES_PROPERTY, propertyList);
addProperty(PARAMETERS_PROPERTY, propertyList);
addProperty(BODY_PROPERTY, propertyList);
PROPERTY_DESCRIPTORS_8_0 = reapPropertyList(propertyList);
}
/**
* Returns a list of structural property descriptors for this node type.
* Clients must not modify the result.
*
* @param apiLevel the API level; one of the AST.JLS* constants
* @return a list of property descriptors (element type:
* {@link StructuralPropertyDescriptor})
*/
public static List propertyDescriptors(int apiLevel) {
return PROPERTY_DESCRIPTORS_8_0;
}
/**
* Indicates whether parentheses are present or not.
* Defaults to <code>true</code>.
*/
private boolean hasParentheses = true;
/**
* The parameter declarations
* (element type: {@link VariableDeclaration}).
* Defaults to an empty list.
*/
private ASTNode.NodeList parameters =
new ASTNode.NodeList(PARAMETERS_PROPERTY);
/**
* The method body.
* The method body; lazily initialized, defaults to an empty Block.
*/
private ASTNode body = null;
/**
* Creates a new AST node for a LambdaExpression declaration owned
* by the given AST.
* <p>
* N.B. This constructor is package-private; all subclasses must be
* declared in the same package; clients are unable to declare
* additional subclasses.
* </p>
*
* @param ast the AST that is to own this node
*/
LambdaExpression(AST ast) {
super(ast);
unsupportedIn2_3_4();
}
/* (omit javadoc for this method)
* Method declared on ASTNode.
*/
final List internalStructuralPropertiesForType(int apiLevel) {
return propertyDescriptors(apiLevel);
}
/* (omit javadoc for this method)
* Method declared on ASTNode.
*/
final boolean internalGetSetBooleanProperty(SimplePropertyDescriptor property, boolean get, boolean value) {
if (property == PARENTHESES_PROPERTY) {
if (get) {
return hasParentheses();
} else {
setParentheses(value);
return false;
}
}
// allow default implementation to flag the error
return super.internalGetSetBooleanProperty(property, get, value);
}
/* (omit javadoc for this method)
* Method declared on ASTNode.
*/
final List internalGetChildListProperty(ChildListPropertyDescriptor property) {
if (property == PARAMETERS_PROPERTY) {
return parameters();
}
// allow default implementation to flag the error
return super.internalGetChildListProperty(property);
}
/* (omit javadoc for this method)
* Method declared on ASTNode.
*/
final ASTNode internalGetSetChildProperty(ChildPropertyDescriptor property, boolean get, ASTNode child) {
if (property == BODY_PROPERTY) {
if (get) {
return getBody();
} else {
setBody( child);
return null;
}
}
// allow default implementation to flag the error
return super.internalGetSetChildProperty(property, get, child);
}
/* (omit javadoc for this method)
* Method declared on ASTNode.
*/
final int getNodeType0() {
return LAMBDA_EXPRESSION;
}
/* (omit javadoc for this method)
* Method declared on ASTNode.
*/
ASTNode clone0(AST target) {
LambdaExpression result = new LambdaExpression(target);
result.setSourceRange(getStartPosition(), getLength());
result.setParentheses(hasParentheses());
result.parameters().addAll(ASTNode.copySubtrees(target, parameters()));
result.setBody(ASTNode.copySubtree(target, getBody()));
return result;
}
/* (omit javadoc for this method)
* Method declared on ASTNode.
*/
final boolean subtreeMatch0(ASTMatcher matcher, Object other) {
// dispatch to correct overloaded match method
return matcher.match(this, other);
}
/* (omit javadoc for this method)
* Method declared on ASTNode.
*/
void accept0(ASTVisitor visitor) {
boolean visitChildren = visitor.visit(this);
if (visitChildren) {
// visit children in normal left to right reading order
acceptChildren(visitor, this.parameters);
acceptChild(visitor, getBody());
}
visitor.endVisit(this);
}
/**
* Returns whether parentheses around the parameters are present or not.
* <p>
* Note that parentheses are required unless {@link #parameters()} contains
* just a single {@link VariableDeclarationFragment}.
* ASTRewrite may ignore this property if necessary.
* </p>
*
* @return <code>true</code> if this lambda expression has parentheses around
* its parameters and <code>false</code> otherwise
*/
public boolean hasParentheses() {
return this.hasParentheses;
}
/**
* Sets whether this lambda expression has parentheses around its parameters or not.
* <p>
* Note that parentheses are required unless {@link #parameters()} contains
* just a single {@link VariableDeclarationFragment}.
* ASTRewrite may ignore this property if necessary.
* </p>
*
* @param hasParentheses <code>true</code> if this lambda expression has parentheses around its parameters
* and <code>false</code> otherwise
*/
public void setParentheses(boolean hasParentheses) {
preValueChange(PARENTHESES_PROPERTY);
this.hasParentheses = hasParentheses;
postValueChange(PARENTHESES_PROPERTY);
}
/**
* Returns the live ordered list of formal parameters of this lambda expression.
* Note that all elements must be of the same type, either
* <ul>
* <li>all {@link SingleVariableDeclaration} (explicit type), or</li>
* <li>all {@link VariableDeclarationFragment} (inferred type).</li>
* </ul>
*
* @return the live list of formal parameters of this lambda expression
* (element type: {@link VariableDeclaration})
*/
public List parameters() {
return this.parameters;
}
/**
* Returns the body of this lambda expression.
*
* @return the lambda expression body, which can be either a {@link Block} or an {@link Expression}
*/
public ASTNode getBody() {
if (this.body == null) {
// lazy init must be thread-safe for readers
synchronized (this) {
if (this.body == null) {
preLazyInit();
this.body = new Block(this.ast);
postLazyInit(this.body, BODY_PROPERTY);
}
}
}
return this.body;
}
/**
* Sets the body of this lambda expression.
*
* @param body a block node or an expression node
* @exception IllegalArgumentException if:
* <ul>
* <li>the node belongs to a different AST</li>
* <li>the node already has a parent</li>
* <li>a cycle in would be created</li>
* <li>body is neither a {@link Block} nor an {@link Expression}</li>
* </ul>
*/
public void setBody(ASTNode body) {
if (!(body instanceof Expression || body instanceof Block)) {
throw new IllegalArgumentException();
}
ASTNode oldChild = this.body;
preReplaceChild(oldChild, body, BODY_PROPERTY);
this.body = body;
postReplaceChild(oldChild, body, BODY_PROPERTY);
}
/**
* Resolves and returns the binding for the lambda expression
* <p>
* Note that bindings are generally unavailable unless requested when the
* AST is being built.
* </p>
*
* @return the binding, or <code>null</code> if the binding cannot be
* resolved
*/
public IMethodBinding resolveMethodBinding() {
return this.ast.getBindingResolver().resolveMethod(this);
}
/* (omit javadoc for this method)
* Method declared on ASTNode.
*/
int memSize() {
return BASE_NODE_SIZE + 3 * 4;
}
/* (omit javadoc for this method)
* Method declared on ASTNode.
*/
int treeSize() {
return
memSize()
+ this.parameters.listSize()
+ (this.body == null ? 0 : getBody().treeSize());
}
}