001 /** 002 * Licensed to the Apache Software Foundation (ASF) under one or more 003 * contributor license agreements. See the NOTICE file distributed with 004 * this work for additional information regarding copyright ownership. 005 * The ASF licenses this file to You under the Apache License, Version 2.0 006 * (the "License"); you may not use this file except in compliance with 007 * the License. You may obtain a copy of the License at 008 * 009 * http://www.apache.org/licenses/LICENSE-2.0 010 * 011 * Unless required by applicable law or agreed to in writing, software 012 * distributed under the License is distributed on an "AS IS" BASIS, 013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 014 * See the License for the specific language governing permissions and 015 * limitations under the License. 016 */ 017 package org.apache.camel.language.simple; 018 019 import org.apache.camel.Exchange; 020 import org.apache.camel.Expression; 021 import org.apache.camel.builder.ExpressionBuilder; 022 import org.apache.camel.language.IllegalSyntaxException; 023 import org.apache.camel.util.ObjectHelper; 024 025 /** 026 * A <a href="http://activemq.apache.org/camel/simple.html">simple language</a> 027 * which maps simple property style notations to access headers and bodies. 028 * Examples of supported expressions are: 029 * <ul> 030 * <li>id to access the inbound message Id</li> 031 * <li>in.body or body to access the inbound body</li> 032 * <li>out.body to access the inbound body</li> 033 * <li>in.header.foo or header.foo to access an inbound header called 'foo'</li> 034 * <li>out.header.foo to access an outbound header called 'foo'</li> 035 * <li>property.foo to access the exchange property called 'foo'</li> 036 * <li>sys.foo to access the system property called 'foo'</li> 037 * </ul> 038 * 039 * @version $Revision: 47086 $ 040 */ 041 public class SimpleLanguage extends AbstractSimpleLanguage { 042 043 public static Expression simple(String expression) { 044 SimpleLanguage language = new SimpleLanguage(); 045 return language.createExpression(expression); 046 } 047 048 protected Expression<Exchange> createSimpleExpression(String expression) { 049 if (ObjectHelper.isEqualToAny(expression, "body", "in.body")) { 050 return ExpressionBuilder.bodyExpression(); 051 } else if (ObjectHelper.equal(expression, "out.body")) { 052 return ExpressionBuilder.outBodyExpression(); 053 } else if (ObjectHelper.equal(expression, "id")) { 054 return ExpressionBuilder.messageIdExpression(); 055 } 056 057 // in header expression 058 String remainder = ifStartsWithReturnRemainder("in.header.", expression); 059 if (remainder == null) { 060 remainder = ifStartsWithReturnRemainder("header.", expression); 061 } 062 if (remainder == null) { 063 remainder = ifStartsWithReturnRemainder("headers.", expression); 064 } 065 if (remainder == null) { 066 remainder = ifStartsWithReturnRemainder("in.headers.", expression); 067 } 068 if (remainder != null) { 069 return ExpressionBuilder.headerExpression(remainder); 070 } 071 072 // out header expression 073 remainder = ifStartsWithReturnRemainder("out.header.", expression); 074 if (remainder == null) { 075 remainder = ifStartsWithReturnRemainder("out.headers.", expression); 076 } 077 if (remainder != null) { 078 return ExpressionBuilder.outHeaderExpression(remainder); 079 } 080 081 // property 082 remainder = ifStartsWithReturnRemainder("property.", expression); 083 if (remainder != null) { 084 return ExpressionBuilder.propertyExpression(remainder); 085 } 086 087 // system property 088 remainder = ifStartsWithReturnRemainder("sys.", expression); 089 if (remainder != null) { 090 return ExpressionBuilder.systemProperty(remainder); 091 } 092 093 throw new IllegalSyntaxException(this, expression); 094 } 095 096 }