001 // Copyright 2004, 2005 The Apache Software Foundation 002 // 003 // Licensed under the Apache License, Version 2.0 (the "License"); 004 // you may not use this file except in compliance with the License. 005 // You may obtain a copy of the License at 006 // 007 // http://www.apache.org/licenses/LICENSE-2.0 008 // 009 // Unless required by applicable law or agreed to in writing, software 010 // distributed under the License is distributed on an "AS IS" BASIS, 011 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 012 // See the License for the specific language governing permissions and 013 // limitations under the License. 014 015 package org.apache.tapestry.engine; 016 017 /** 018 * Basic support for application monitoring and metrics. 019 * This interface defines events; the implementation 020 * decides what to do with them (such as record them to a database). 021 * 022 * @author Howard Lewis Ship 023 * 024 **/ 025 026 public interface IMonitor 027 { 028 /** 029 * Invoked before constructing a page. 030 * 031 **/ 032 033 public void pageCreateBegin(String pageName); 034 035 /** 036 * Invoked after successfully constructing a page and all of its components. 037 * 038 **/ 039 040 public void pageCreateEnd(String pageName); 041 042 /** 043 * Invoked when a page is loaded. This includes time to locate or create an instance 044 * of the page and rollback its state (to any previously recorded value). 045 * 046 **/ 047 048 public void pageLoadBegin(String pageName); 049 050 /** 051 * Invoked once a page is completely loaded and rolled back to its prior state. 052 * 053 **/ 054 055 public void pageLoadEnd(String pageName); 056 057 /** 058 * Invoked before a page render begins. 059 * 060 **/ 061 062 public void pageRenderBegin(String pageName); 063 064 /** 065 * Invoked after a page has succesfully rendered. 066 * 067 **/ 068 069 public void pageRenderEnd(String pageName); 070 071 /** 072 * Invoked before a page rewind (to respond to an action) begins. 073 * 074 **/ 075 076 public void pageRewindBegin(String pageName); 077 078 /** 079 * Invoked after a page has succesfully been rewound (which includes 080 * any activity related to the action listener). 081 * 082 **/ 083 084 public void pageRewindEnd(String pageName); 085 086 /** 087 * Invoked when a service begins processing. 088 * 089 **/ 090 091 public void serviceBegin(String serviceName, String detailMessage); 092 093 /** 094 * Invoked when a service successfully ends. 095 * 096 **/ 097 098 public void serviceEnd(String serviceName); 099 100 /** 101 * Invoked when a service throws an exception rather than completing normally. 102 * Processing of the request may continue with the display of an exception 103 * page. 104 * 105 * <p> 106 * serviceException() is always invoked <em>before</em> 107 * {@link #serviceEnd(String)}. 108 * 109 **/ 110 111 public void serviceException(Throwable exception); 112 113 /** 114 * Invoked when a session is initiated. This is typically 115 * done from the implementation of the home service. 116 * 117 **/ 118 119 public void sessionBegin(); 120 }