001 package org.apache.turbine.services.velocity; 002 003 004 /* 005 * Licensed to the Apache Software Foundation (ASF) under one 006 * or more contributor license agreements. See the NOTICE file 007 * distributed with this work for additional information 008 * regarding copyright ownership. The ASF licenses this file 009 * to you under the Apache License, Version 2.0 (the 010 * "License"); you may not use this file except in compliance 011 * with the License. You may obtain a copy of the License at 012 * 013 * http://www.apache.org/licenses/LICENSE-2.0 014 * 015 * Unless required by applicable law or agreed to in writing, 016 * software distributed under the License is distributed on an 017 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY 018 * KIND, either express or implied. See the License for the 019 * specific language governing permissions and limitations 020 * under the License. 021 */ 022 023 024 import java.io.OutputStream; 025 import java.io.Writer; 026 027 import org.apache.turbine.pipeline.PipelineData; 028 import org.apache.turbine.services.Service; 029 import org.apache.turbine.util.RunData; 030 import org.apache.turbine.util.TurbineException; 031 032 import org.apache.velocity.context.Context; 033 034 /** 035 * Implementations of the VelocityService interface. 036 * 037 * @author <a href="mailto:john.mcnally@clearink.com">John D. McNally</a> 038 * @author <a href="mailto:mbryson@mont.mindspring.com">Dave Bryson</a> 039 * @author <a href="mailto:jvanzyl@periapt.com">Jason van Zyl</a> 040 * @author <a href="mailto:hps@intermeta.de">Henning P. Schmiedehausen</a> 041 * @author <a href="mailto:peter@courcoux.biz">Peter Courcoux</a> 042 * @version $Id: VelocityService.java 615328 2008-01-25 20:25:05Z tv $ 043 */ 044 public interface VelocityService 045 extends Service 046 { 047 /** The Service Name */ 048 String SERVICE_NAME = "VelocityService"; 049 050 /** Key for storing the Context in the RunData object */ 051 String CONTEXT = "VELOCITY_CONTEXT"; 052 053 /** The default extension of Velocity Pages */ 054 String VELOCITY_EXTENSION = "vm"; 055 056 /** The Key for storing the RunData Object in the Context */ 057 String RUNDATA_KEY = "data"; 058 059 /** The Key for storing the PipelineData Object in the Context */ 060 String PIPELINEDATA_KEY = "pipelineData"; 061 062 /** Shall we catch Velocity Errors and report them? */ 063 String CATCH_ERRORS_KEY = "catch.errors"; 064 065 /** Default: Yes */ 066 boolean CATCH_ERRORS_DEFAULT = true; 067 068 /** 069 * Process the request and fill in the template with the values 070 * you set in the Context. 071 * 072 * @param context A Context. 073 * @param template A String with the filename of the template. 074 * @return The process template as a String. 075 * @exception Exception a generic exception. 076 */ 077 String handleRequest(Context context, String template) 078 throws Exception; 079 080 /** 081 * Process the request and fill in the template with the values 082 * you set in the Context. 083 * 084 * @param context A Context. 085 * @param filename A String with the filename of the template. 086 * @param out A OutputStream where we will write the process template as 087 * a String. 088 * @throws TurbineException Any exception trown while processing will be 089 * wrapped into a TurbineException and rethrown. 090 */ 091 void handleRequest(Context context, String filename, OutputStream out) 092 throws TurbineException; 093 094 /** 095 * Process the request and fill in the template with the values 096 * you set in the Context. 097 * 098 * @param context A Context. 099 * @param filename A String with the filename of the template. 100 * @param writer A Writer where we will write the process template as 101 * a String. 102 * @throws TurbineException Any exception trown while processing will be 103 * wrapped into a TurbineException and rethrown. 104 */ 105 void handleRequest(Context context, String filename, Writer writer) 106 throws TurbineException; 107 108 /** 109 * Create an empty WebContext object. 110 * 111 * @return An empty WebContext object. 112 */ 113 Context getContext(); 114 115 /** 116 * This method returns a new, empty Context object. 117 * 118 * @return A WebContext. 119 */ 120 Context getNewContext(); 121 122 /** 123 * Create a Context from the RunData object. Adds a pointer to 124 * the RunData object to the Context so that RunData is available in 125 * the templates. 126 * 127 * @param data The Turbine RunData object. 128 * @return A clone of the Context needed by Velocity. 129 */ 130 Context getContext(RunData data); 131 132 /** 133 * Create a Context from the RunData object. Adds a pointer to 134 * the RunData object to the Context so that RunData is available in 135 * the templates. 136 * 137 * @param data The Turbine RunData object. 138 * @return A clone of the Context needed by Velocity. 139 */ 140 Context getContext(PipelineData pipelineData); 141 142 143 144 /** 145 * Performs post-request actions (releases context 146 * tools back to the object pool). 147 * 148 * @param context a Velocity Context 149 */ 150 void requestFinished(Context context); 151 }