| /** |
| * 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.activemq.filter; |
| |
| import java.math.BigDecimal; |
| |
| import javax.jms.JMSException; |
| |
| /** |
| * Represents a constant expression |
| * |
| * |
| */ |
| public class ConstantExpression implements Expression { |
| |
| static class BooleanConstantExpression extends ConstantExpression implements BooleanExpression { |
| public BooleanConstantExpression(Object value) { |
| super(value); |
| } |
| |
| public boolean matches(MessageEvaluationContext message) throws JMSException { |
| Object object = evaluate(message); |
| return object != null && object == Boolean.TRUE; |
| } |
| } |
| |
| public static final BooleanConstantExpression NULL = new BooleanConstantExpression(null); |
| public static final BooleanConstantExpression TRUE = new BooleanConstantExpression(Boolean.TRUE); |
| public static final BooleanConstantExpression FALSE = new BooleanConstantExpression(Boolean.FALSE); |
| |
| private Object value; |
| |
| public ConstantExpression(Object value) { |
| this.value = value; |
| } |
| |
| public static ConstantExpression createFromDecimal(String text) { |
| |
| // Strip off the 'l' or 'L' if needed. |
| if (text.endsWith("l") || text.endsWith("L")) { |
| text = text.substring(0, text.length() - 1); |
| } |
| |
| Number value; |
| try { |
| value = new Long(text); |
| } catch (NumberFormatException e) { |
| // The number may be too big to fit in a long. |
| value = new BigDecimal(text); |
| } |
| |
| long l = value.longValue(); |
| if (Integer.MIN_VALUE <= l && l <= Integer.MAX_VALUE) { |
| value = Integer.valueOf(value.intValue()); |
| } |
| return new ConstantExpression(value); |
| } |
| |
| public static ConstantExpression createFromHex(String text) { |
| Number value = Long.valueOf(Long.parseLong(text.substring(2), 16)); |
| long l = value.longValue(); |
| if (Integer.MIN_VALUE <= l && l <= Integer.MAX_VALUE) { |
| value = Integer.valueOf(value.intValue()); |
| } |
| return new ConstantExpression(value); |
| } |
| |
| public static ConstantExpression createFromOctal(String text) { |
| Number value = Long.valueOf(Long.parseLong(text, 8)); |
| long l = value.longValue(); |
| if (Integer.MIN_VALUE <= l && l <= Integer.MAX_VALUE) { |
| value = Integer.valueOf(value.intValue()); |
| } |
| return new ConstantExpression(value); |
| } |
| |
| public static ConstantExpression createFloat(String text) { |
| Number value = new Double(text); |
| return new ConstantExpression(value); |
| } |
| |
| public Object evaluate(MessageEvaluationContext message) throws JMSException { |
| return value; |
| } |
| |
| public Object getValue() { |
| return value; |
| } |
| |
| /** |
| * @see java.lang.Object#toString() |
| */ |
| public String toString() { |
| if (value == null) { |
| return "NULL"; |
| } |
| if (value instanceof Boolean) { |
| return ((Boolean)value).booleanValue() ? "TRUE" : "FALSE"; |
| } |
| if (value instanceof String) { |
| return encodeString((String)value); |
| } |
| return value.toString(); |
| } |
| |
| /** |
| * TODO: more efficient hashCode() |
| * |
| * @see java.lang.Object#hashCode() |
| */ |
| public int hashCode() { |
| return toString().hashCode(); |
| } |
| |
| /** |
| * TODO: more efficient hashCode() |
| * |
| * @see java.lang.Object#equals(java.lang.Object) |
| */ |
| public boolean equals(Object o) { |
| |
| if (o == null || !this.getClass().equals(o.getClass())) { |
| return false; |
| } |
| return toString().equals(o.toString()); |
| |
| } |
| |
| /** |
| * Encodes the value of string so that it looks like it would look like when |
| * it was provided in a selector. |
| * |
| * @param string |
| * @return |
| */ |
| public static String encodeString(String s) { |
| StringBuffer b = new StringBuffer(); |
| b.append('\''); |
| for (int i = 0; i < s.length(); i++) { |
| char c = s.charAt(i); |
| if (c == '\'') { |
| b.append(c); |
| } |
| b.append(c); |
| } |
| b.append('\''); |
| return b.toString(); |
| } |
| |
| } |