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 */ 017package org.apache.camel.processor; 018 019import org.apache.camel.AsyncCallback; 020import org.apache.camel.AsyncProcessor; 021import org.apache.camel.Exchange; 022import org.apache.camel.Expression; 023import org.apache.camel.Traceable; 024import org.apache.camel.spi.IdAware; 025import org.apache.camel.support.ServiceSupport; 026import org.apache.camel.util.AsyncProcessorHelper; 027import org.apache.camel.util.CamelLogger; 028 029/** 030 * A processor which evaluates an {@link Expression} and logs it. 031 * 032 * @version 033 */ 034public class LogProcessor extends ServiceSupport implements AsyncProcessor, Traceable, IdAware { 035 036 private String id; 037 private final Expression expression; 038 private final CamelLogger logger; 039 040 public LogProcessor(Expression expression, CamelLogger logger) { 041 this.expression = expression; 042 this.logger = logger; 043 } 044 045 public void process(Exchange exchange) throws Exception { 046 AsyncProcessorHelper.process(this, exchange); 047 } 048 049 @Override 050 public boolean process(Exchange exchange, AsyncCallback callback) { 051 try { 052 if (logger.shouldLog()) { 053 String msg = expression.evaluate(exchange, String.class); 054 logger.doLog(msg); 055 } 056 } catch (Exception e) { 057 exchange.setException(e); 058 } finally { 059 // callback must be invoked 060 callback.done(true); 061 } 062 return true; 063 } 064 065 @Override 066 public String toString() { 067 return "Log(" + logger.getLog().getName() + ")[" + expression + "]"; 068 } 069 070 public String getTraceLabel() { 071 return "log[" + expression + "]"; 072 } 073 074 public String getId() { 075 return id; 076 } 077 078 public void setId(String id) { 079 this.id = id; 080 } 081 082 public Expression getExpression() { 083 return expression; 084 } 085 086 public CamelLogger getLogger() { 087 return logger; 088 } 089 090 @Override 091 protected void doStart() throws Exception { 092 // noop 093 } 094 095 @Override 096 protected void doStop() throws Exception { 097 // noop 098 } 099}