| /******************************************************************************* |
| * Copyright (c) 2009, 2010 Cloudsmith Inc. 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: |
| * Cloudsmith Inc. - initial API and implementation |
| *******************************************************************************/ |
| package org.eclipse.equinox.internal.p2.metadata.expression; |
| |
| import org.eclipse.equinox.p2.metadata.expression.IEvaluationContext; |
| |
| /** |
| * The abstract base class for the indexed and keyed parameters |
| */ |
| public class Parameter extends Expression { |
| final int position; |
| |
| Parameter(int position) { |
| this.position = position; |
| } |
| |
| public int compareTo(Expression e) { |
| int cmp = super.compareTo(e); |
| if (cmp == 0) |
| cmp = position - ((Parameter) e).position; |
| return cmp; |
| } |
| |
| public boolean equals(Object o) { |
| if (o == this) |
| return true; |
| if (o == null) |
| return false; |
| return getClass() == o.getClass() && position == ((Parameter) o).position; |
| } |
| |
| public Object evaluate(IEvaluationContext context) { |
| return context.getParameter(position); |
| } |
| |
| public int getExpressionType() { |
| return TYPE_PARAMETER; |
| } |
| |
| public String getOperator() { |
| return OPERATOR_PARAMETER; |
| } |
| |
| public int getPriority() { |
| return PRIORITY_VARIABLE; |
| } |
| |
| public int hashCode() { |
| return 31 * (1 + position); |
| } |
| |
| public void toString(StringBuffer bld, Variable rootVariable) { |
| bld.append('$'); |
| bld.append(position); |
| } |
| } |