001package org.apache.turbine.modules.screens; 002 003/* 004 * Licensed to the Apache Software Foundation (ASF) under one 005 * or more contributor license agreements. See the NOTICE file 006 * distributed with this work for additional information 007 * regarding copyright ownership. The ASF licenses this file 008 * to you under the Apache License, Version 2.0 (the 009 * "License"); you may not use this file except in compliance 010 * with the License. You may obtain a copy of the License at 011 * 012 * http://www.apache.org/licenses/LICENSE-2.0 013 * 014 * Unless required by applicable law or agreed to in writing, 015 * software distributed under the License is distributed on an 016 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY 017 * KIND, either express or implied. See the License for the 018 * specific language governing permissions and limitations 019 * under the License. 020 */ 021 022import org.apache.commons.lang.StringUtils; 023import org.apache.commons.lang.exception.ExceptionUtils; 024import org.apache.turbine.TurbineConstants; 025import org.apache.turbine.pipeline.PipelineData; 026import org.apache.turbine.util.RunData; 027import org.apache.velocity.context.Context; 028 029/** 030 * VelocityDirectScreen is a screen class which returns its output 031 * directly to the output stream. It can be used if buffering an 032 * output screen isn't possible or the result doesn't fit in the 033 * memory. 034 * <p> 035 * @author <a href="mailto:mbryson@mont.mindspring.com">Dave Bryson</a> 036 * @author <a href="mailto:hps@intermeta.de">Henning P. Schmiedehausen</a> 037 * @author <a href="mailto:peter@courcoux.biz">Peter Courcoux</a> 038 * @version $Id: VelocityDirectScreen.java 1773378 2016-12-09 13:19:59Z tv $ 039 */ 040public class VelocityDirectScreen 041 extends VelocityScreen 042{ 043 /** The prefix for lookup up screen pages */ 044 private String prefix = getPrefix() + "/"; 045 046 /** 047 * This builds the Velocity template. 048 * 049 * @param pipelineData Turbine information. 050 * @return the content of the screen 051 * @throws Exception a generic exception. 052 */ 053 @Override 054 public String buildTemplate(PipelineData pipelineData) 055 throws Exception 056 { 057 RunData data = getRunData(pipelineData); 058 Context context = velocity.getContext(pipelineData); 059 060 String screenTemplate = data.getTemplateInfo().getScreenTemplate(); 061 String templateName 062 = templateService.getScreenTemplateName(screenTemplate); 063 064 // The Template Service could not find the Screen 065 if (StringUtils.isEmpty(templateName)) 066 { 067 log.error("Screen " + screenTemplate + " not found!"); 068 throw new Exception("Could not find screen for " + screenTemplate); 069 } 070 071 try 072 { 073 velocity.handleRequest(context, 074 prefix + templateName, 075 data.getResponse().getOutputStream()); 076 077 } 078 catch (Exception e) 079 { 080 // If there is an error, build a $processingException and 081 // attempt to call the error.vm template in the screens 082 // directory. 083 context.put (TurbineConstants.PROCESSING_EXCEPTION_PLACEHOLDER, e.toString()); 084 context.put (TurbineConstants.STACK_TRACE_PLACEHOLDER, ExceptionUtils.getStackTrace(e)); 085 086 velocity.handleRequest(context, prefix + templateError, 087 data.getResponse().getOutputStream()); 088 } 089 090 return null; 091 } 092}