Java tutorial
/******************************************************************************* * Copyright (c) 2000, 2013 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.core.dom; import java.util.ArrayList; import java.util.List; /** * Assert statement AST node type. * * <pre> * AssertStatement: * <b>assert</b> Expression [ <b>:</b> Expression ] <b>;</b> * </pre> * * @since 2.0 * @noinstantiate This class is not intended to be instantiated by clients. */ @SuppressWarnings("rawtypes") public class AssertStatement extends Statement { /** * The "expression" structural property of this node type (child type: {@link Expression}). * @since 3.0 */ public static final ChildPropertyDescriptor EXPRESSION_PROPERTY = new ChildPropertyDescriptor( AssertStatement.class, "expression", Expression.class, MANDATORY, CYCLE_RISK); //$NON-NLS-1$ /** * The "message" structural property of this node type (child type: {@link Expression}). * @since 3.0 */ public static final ChildPropertyDescriptor MESSAGE_PROPERTY = new ChildPropertyDescriptor( AssertStatement.class, "message", Expression.class, OPTIONAL, CYCLE_RISK); //$NON-NLS-1$ /** * A list of property descriptors (element type: * {@link StructuralPropertyDescriptor}), * or null if uninitialized. */ private static final List PROPERTY_DESCRIPTORS; static { List properyList = new ArrayList(3); createPropertyList(AssertStatement.class, properyList); addProperty(EXPRESSION_PROPERTY, properyList); addProperty(MESSAGE_PROPERTY, properyList); PROPERTY_DESCRIPTORS = reapPropertyList(properyList); } /** * 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 * <code>AST.JLS*</code> constants * @return a list of property descriptors (element type: * {@link StructuralPropertyDescriptor}) * @since 3.0 */ public static List propertyDescriptors(int apiLevel) { return PROPERTY_DESCRIPTORS; } /** * The expression; lazily initialized; defaults to a unspecified, but legal, * expression. */ private Expression expression = null; /** * The message expression; <code>null</code> for none; defaults to none. */ private Expression optionalMessageExpression = null; /** * Creates a new unparented assert statement node owned by the given * AST. By default, the assert statement has an unspecified, but legal, * expression, and not message expression. * <p> * N.B. This constructor is package-private. * </p> * * @param ast the AST that is to own this node */ AssertStatement(AST ast) { super(ast); } @Override final List internalStructuralPropertiesForType(int apiLevel) { return propertyDescriptors(apiLevel); } @Override final ASTNode internalGetSetChildProperty(ChildPropertyDescriptor property, boolean get, ASTNode child) { if (property == EXPRESSION_PROPERTY) { if (get) { return getExpression(); } else { setExpression((Expression) child); return null; } } if (property == MESSAGE_PROPERTY) { if (get) { return getMessage(); } else { setMessage((Expression) child); return null; } } // allow default implementation to flag the error return super.internalGetSetChildProperty(property, get, child); } @Override final int getNodeType0() { return ASSERT_STATEMENT; } @Override ASTNode clone0(AST target) { AssertStatement result = new AssertStatement(target); result.setSourceRange(getStartPosition(), getLength()); result.copyLeadingComment(this); result.setExpression((Expression) ASTNode.copySubtree(target, getExpression())); result.setMessage((Expression) ASTNode.copySubtree(target, getMessage())); return result; } @Override final boolean subtreeMatch0(ASTMatcher matcher, Object other) { // dispatch to correct overloaded match method return matcher.match(this, other); } @Override void accept0(ASTVisitor visitor) { boolean visitChildren = visitor.visit(this); if (visitChildren) { // visit children in normal left to right reading order acceptChild(visitor, getExpression()); acceptChild(visitor, getMessage()); } visitor.endVisit(this); } /** * Returns the first expression of this assert statement. * * @return the expression node */ public Expression getExpression() { if (this.expression == null) { // lazy init must be thread-safe for readers synchronized (this) { if (this.expression == null) { preLazyInit(); this.expression = new SimpleName(this.ast); postLazyInit(this.expression, EXPRESSION_PROPERTY); } } } return this.expression; } /** * Sets the first expression of this assert statement. * * @param expression the new 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> * </ul> */ public void setExpression(Expression expression) { if (expression == null) { throw new IllegalArgumentException(); } // an AssertStatement may occur inside an Expression - must check cycles ASTNode oldChild = this.expression; preReplaceChild(oldChild, expression, EXPRESSION_PROPERTY); this.expression = expression; postReplaceChild(oldChild, expression, EXPRESSION_PROPERTY); } /** * Returns the message expression of this assert statement, or * <code>null</code> if there is none. * * @return the message expression node, or <code>null</code> if there * is none */ public Expression getMessage() { return this.optionalMessageExpression; } /** * Sets or clears the message expression of this assert statement. * * @param expression the message expression node, or <code>null</code> if * there is none * @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> * </ul> */ public void setMessage(Expression expression) { // an AsertStatement may occur inside an Expression - must check cycles ASTNode oldChild = this.optionalMessageExpression; preReplaceChild(oldChild, expression, MESSAGE_PROPERTY); this.optionalMessageExpression = expression; postReplaceChild(oldChild, expression, MESSAGE_PROPERTY); } @Override int memSize() { return super.memSize() + 2 * 4; } @Override int treeSize() { return memSize() + (this.expression == null ? 0 : getExpression().treeSize()) + (this.optionalMessageExpression == null ? 0 : getMessage().treeSize()); } }