| /* |
| * 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.commons.proxy.interceptor; |
| |
| import org.apache.commons.logging.Log; |
| import org.apache.commons.proxy.ProxyUtils; |
| import org.apache.commons.proxy.Interceptor; |
| import org.apache.commons.proxy.Invocation; |
| |
| /** |
| * An interceptor which logs each method invocation. |
| * <b>Note</b>: The implementation of this class was borrowed from |
| * HiveMind's logging interceptor. |
| * |
| * <p> |
| * <b>Dependencies</b>: |
| * <ul> |
| * <li>Apache Commons Logging version 1.0.4 or greater</li> |
| * </ul> |
| * </p> |
| * @author James Carman |
| * @since 1.0 |
| */ |
| public class LoggingInterceptor implements Interceptor |
| { |
| //---------------------------------------------------------------------------------------------------------------------- |
| // Fields |
| //---------------------------------------------------------------------------------------------------------------------- |
| |
| private static final int BUFFER_SIZE = 100; |
| private Log log; |
| |
| //---------------------------------------------------------------------------------------------------------------------- |
| // Constructors |
| //---------------------------------------------------------------------------------------------------------------------- |
| |
| public LoggingInterceptor( Log log ) |
| { |
| this.log = log; |
| } |
| |
| //---------------------------------------------------------------------------------------------------------------------- |
| // MethodInterceptor Implementation |
| //---------------------------------------------------------------------------------------------------------------------- |
| |
| public Object intercept( Invocation invocation ) throws Throwable |
| { |
| if( log.isDebugEnabled() ) |
| { |
| final String methodName = invocation.getMethod().getName(); |
| entry( methodName, invocation.getArguments() ); |
| try |
| { |
| Object result = invocation.proceed(); |
| if( Void.TYPE.equals( invocation.getMethod().getReturnType() ) ) |
| { |
| voidExit( methodName ); |
| } |
| else |
| { |
| exit( methodName, result ); |
| } |
| return result; |
| } |
| catch( Throwable t ) |
| { |
| exception( methodName, t ); |
| throw t; |
| } |
| } |
| else |
| { |
| return invocation.proceed(); |
| } |
| } |
| |
| //---------------------------------------------------------------------------------------------------------------------- |
| // Other Methods |
| //---------------------------------------------------------------------------------------------------------------------- |
| |
| private void entry( String methodName, Object[] args ) |
| { |
| StringBuffer buffer = new StringBuffer( BUFFER_SIZE ); |
| buffer.append( "BEGIN " ); |
| buffer.append( methodName ); |
| buffer.append( "(" ); |
| int count = args.length; |
| for( int i = 0; i < count; i++ ) |
| { |
| Object arg = args[i]; |
| if( i > 0 ) |
| { |
| buffer.append( ", " ); |
| } |
| convert( buffer, arg ); |
| } |
| buffer.append( ")" ); |
| log.debug( buffer.toString() ); |
| } |
| |
| private void convert( StringBuffer buffer, Object input ) |
| { |
| if( input == null ) |
| { |
| buffer.append( "<null>" ); |
| return; |
| } |
| |
| // Primitive types, and non-object arrays |
| // use toString(). Less than ideal for int[], etc., but |
| // that's a lot of work for a rare case. |
| if( !( input instanceof Object[] ) ) |
| { |
| buffer.append( input.toString() ); |
| return; |
| } |
| buffer.append( "(" ); |
| buffer.append( ProxyUtils.getJavaClassName( input.getClass() ) ); |
| buffer.append( "){" ); |
| Object[] array = ( Object[] ) input; |
| int count = array.length; |
| for( int i = 0; i < count; i++ ) |
| { |
| if( i > 0 ) |
| { |
| buffer.append( ", " ); |
| } |
| |
| // We use convert() again, because it could be a multi-dimensional array |
| // (god help us) where each element must be converted. |
| convert( buffer, array[i] ); |
| } |
| buffer.append( "}" ); |
| } |
| |
| private void exception( String methodName, Throwable t ) |
| { |
| StringBuffer buffer = new StringBuffer( BUFFER_SIZE ); |
| buffer.append( "EXCEPTION " ); |
| buffer.append( methodName ); |
| buffer.append( "() -- " ); |
| buffer.append( t.getClass().getName() ); |
| log.debug( buffer.toString(), t ); |
| } |
| |
| private void exit( String methodName, Object result ) |
| { |
| StringBuffer buffer = new StringBuffer( BUFFER_SIZE ); |
| buffer.append( "END " ); |
| buffer.append( methodName ); |
| buffer.append( "() [" ); |
| convert( buffer, result ); |
| buffer.append( "]" ); |
| log.debug( buffer.toString() ); |
| } |
| |
| private void voidExit( String methodName ) |
| { |
| StringBuffer buffer = new StringBuffer( BUFFER_SIZE ); |
| buffer.append( "END " ); |
| buffer.append( methodName ); |
| buffer.append( "()" ); |
| log.debug( buffer.toString() ); |
| } |
| } |
| |