/*******************************************************************************
* Copyright (c) 2000, 2006 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.core.internal.expressions;
import org.w3c.dom.Element;
import org.eclipse.core.runtime.Assert;
import org.eclipse.core.runtime.CoreException;
import org.eclipse.core.runtime.IConfigurationElement;
import org.eclipse.core.expressions.EvaluationContext;
import org.eclipse.core.expressions.EvaluationResult;
import org.eclipse.core.expressions.ExpressionInfo;
import org.eclipse.core.expressions.IEvaluationContext;
public class WithExpression extends CompositeExpression {
private String fVariable;
private static final String ATT_VARIABLE= "variable"; //$NON-NLS-1$
/**
* The seed for the hash code for all with expressions.
*/
private static final int HASH_INITIAL= WithExpression.class.getName().hashCode();
public WithExpression(IConfigurationElement configElement) throws CoreException {
fVariable= configElement.getAttribute(ATT_VARIABLE);
Expressions.checkAttribute(ATT_VARIABLE, fVariable);
}
public WithExpression(Element element) throws CoreException {
fVariable= element.getAttribute(ATT_VARIABLE);
Expressions.checkAttribute(ATT_VARIABLE, fVariable.length() > 0 ? fVariable : null);
}
public WithExpression(String variable) {
Assert.isNotNull(variable);
fVariable= variable;
}
public boolean equals(final Object object) {
if (!(object instanceof WithExpression))
return false;
final WithExpression that= (WithExpression)object;
return this.fVariable.equals(that.fVariable) && equals(this.fExpressions, that.fExpressions);
}
protected int computeHashCode() {
return HASH_INITIAL * HASH_FACTOR + hashCode(fExpressions)
* HASH_FACTOR + fVariable.hashCode();
}
public EvaluationResult evaluate(IEvaluationContext context) throws CoreException {
Object variable= context.getVariable(fVariable);
if (variable == null) {
throw new CoreException(new ExpressionStatus(
ExpressionStatus.VARIABLE_NOT_DEFINED,
Messages.format(ExpressionMessages.WithExpression_variable_not_defined, fVariable)));
}
return evaluateAnd(new EvaluationContext(context, variable));
}
public void collectExpressionInfo(ExpressionInfo info) {
ExpressionInfo other= new ExpressionInfo();
super.collectExpressionInfo(other);
if (other.hasDefaultVariableAccess()) {
info.addVariableNameAccess(fVariable);
}
info.mergeExceptDefaultVariable(other);
}
}