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.builder.xml; 018 019 import java.util.HashMap; 020 import java.util.Map; 021 022 import javax.xml.namespace.QName; 023 import javax.xml.xpath.XPathVariableResolver; 024 025 import org.apache.camel.Exchange; 026 import org.apache.camel.Message; 027 import org.apache.commons.logging.Log; 028 import org.apache.commons.logging.LogFactory; 029 030 import static org.apache.camel.builder.xml.Namespaces.ENVIRONMENT_VARIABLES; 031 import static org.apache.camel.builder.xml.Namespaces.EXCHANGE_PROPERTY; 032 import static org.apache.camel.builder.xml.Namespaces.IN_NAMESPACE; 033 import static org.apache.camel.builder.xml.Namespaces.OUT_NAMESPACE; 034 import static org.apache.camel.builder.xml.Namespaces.SYSTEM_PROPERTIES_NAMESPACE; 035 036 /** 037 * A variable resolver for XPath expressions which support properties on the 038 * messge, exchange as well as making system properties and environment 039 * properties available. 040 * 041 * @version $Revision: 35332 $ 042 */ 043 public class MessageVariableResolver implements XPathVariableResolver { 044 045 private static final transient Log LOG = LogFactory.getLog(MessageVariableResolver.class); 046 047 private Exchange exchange; 048 private Map<String, Object> variables = new HashMap<String, Object>(); 049 050 public Exchange getExchange() { 051 return exchange; 052 } 053 054 public void setExchange(Exchange exchange) { 055 this.exchange = exchange; 056 } 057 058 public Object resolveVariable(QName name) { 059 String uri = name.getNamespaceURI(); 060 String localPart = name.getLocalPart(); 061 Object answer = null; 062 063 Message in = exchange.getIn(); 064 if (uri == null || uri.length() == 0) { 065 answer = variables.get(localPart); 066 if (answer == null) { 067 Message message = in; 068 if (message != null) { 069 answer = message.getHeader(localPart); 070 } 071 if (answer == null) { 072 answer = exchange.getProperty(localPart); 073 } 074 } 075 } else if (uri.equals(SYSTEM_PROPERTIES_NAMESPACE)) { 076 try { 077 answer = System.getProperty(localPart); 078 } catch (Exception e) { 079 LOG 080 .debug("Security exception evaluating system property: " + localPart + ". Reason: " + e, 081 e); 082 } 083 } else if (uri.equals(ENVIRONMENT_VARIABLES)) { 084 answer = System.getenv().get(localPart); 085 } else if (uri.equals(EXCHANGE_PROPERTY)) { 086 answer = exchange.getProperty(localPart); 087 } else if (uri.equals(IN_NAMESPACE)) { 088 answer = in.getHeader(localPart); 089 if (answer == null && localPart.equals("body")) { 090 answer = in.getBody(); 091 } 092 } else if (uri.equals(OUT_NAMESPACE)) { 093 Message out = exchange.getOut(false); 094 if (out != null) { 095 answer = out.getHeader(localPart); 096 if (answer == null && localPart.equals("body")) { 097 answer = out.getBody(); 098 } 099 } 100 } 101 102 // TODO support exposing CamelContext properties/resources via XPath? 103 return answer; 104 } 105 106 public void addVariable(String localPart, Object value) { 107 variables.put(localPart, value); 108 } 109 }