| /** |
| * |
| * Licensed to the Apache Software Foundation (ASF) under one or more |
| * contributor license agreements. See the NOTICE file distributed with |
| * this work for additional information regarding copyright ownership. |
| * The ASF licenses this file to You under the Apache License, Version 2.0 |
| * (the "License"); you may not use this file except in compliance with |
| * the License. You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| package org.apache.qpid.server.filter; |
| // |
| // Based on like named file from r450141 of the Apache ActiveMQ project <http://www.activemq.org/site/home.html> |
| // |
| |
| import org.apache.qpid.AMQException; |
| import org.apache.qpid.server.queue.AMQMessage; |
| import org.apache.qpid.server.queue.Filterable; |
| |
| /** |
| * A filter performing a comparison of two objects |
| */ |
| public abstract class LogicExpression<E extends Exception> extends BinaryExpression<E> implements BooleanExpression<E> |
| { |
| |
| public static<E extends Exception> BooleanExpression createOR(BooleanExpression<E> lvalue, BooleanExpression<E> rvalue) |
| { |
| return new OrExpression(lvalue, rvalue); |
| } |
| |
| public static<E extends Exception> BooleanExpression createAND(BooleanExpression<E> lvalue, BooleanExpression<E> rvalue) |
| { |
| return new AndExpression(lvalue, rvalue); |
| } |
| |
| /** |
| * @param left |
| * @param right |
| */ |
| public LogicExpression(BooleanExpression left, BooleanExpression right) |
| { |
| super(left, right); |
| } |
| |
| public abstract Object evaluate(Filterable<E> message) throws E; |
| |
| public boolean matches(Filterable<E> message) throws E |
| { |
| Object object = evaluate(message); |
| |
| return (object != null) && (object == Boolean.TRUE); |
| } |
| |
| private static class OrExpression<E extends Exception> extends LogicExpression<E> |
| { |
| public OrExpression(final BooleanExpression<E> lvalue, final BooleanExpression<E> rvalue) |
| { |
| super(lvalue, rvalue); |
| } |
| |
| public Object evaluate(Filterable<E> message) throws E |
| { |
| |
| Boolean lv = (Boolean) left.evaluate(message); |
| // Can we do an OR shortcut?? |
| if ((lv != null) && lv.booleanValue()) |
| { |
| return Boolean.TRUE; |
| } |
| |
| Boolean rv = (Boolean) right.evaluate(message); |
| |
| return (rv == null) ? null : rv; |
| } |
| |
| public String getExpressionSymbol() |
| { |
| return "OR"; |
| } |
| } |
| |
| private static class AndExpression<E extends Exception> extends LogicExpression<E> |
| { |
| public AndExpression(final BooleanExpression<E> lvalue, final BooleanExpression<E> rvalue) |
| { |
| super(lvalue, rvalue); |
| } |
| |
| public Object evaluate(Filterable<E> message) throws E |
| { |
| |
| Boolean lv = (Boolean) left.evaluate(message); |
| |
| // Can we do an AND shortcut?? |
| if (lv == null) |
| { |
| return null; |
| } |
| |
| if (!lv.booleanValue()) |
| { |
| return Boolean.FALSE; |
| } |
| |
| Boolean rv = (Boolean) right.evaluate(message); |
| |
| return (rv == null) ? null : rv; |
| } |
| |
| public String getExpressionSymbol() |
| { |
| return "AND"; |
| } |
| } |
| } |