001package org.apache.turbine.util.template; 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 024import org.apache.commons.logging.Log; 025import org.apache.commons.logging.LogFactory; 026import org.apache.turbine.modules.Screen; 027import org.apache.turbine.modules.ScreenLoader; 028import org.apache.turbine.services.assemblerbroker.TurbineAssemblerBroker; 029import org.apache.turbine.util.RunData; 030 031/** 032 * Returns output of a Screen module. An instance of this is 033 * placed in the Velocity context by the VelocityDirectLayout. This 034 * allows the screen to be executed only at rendering. 035 * Here's how it's used in a template: 036 * 037 * <p> 038 * <code> 039 * $screen_placeholder 040 * </code> 041 * <p> 042 * <code> 043 * $screen_placeholder.setScreen("Test") 044 * </code> 045 * </p> 046 * 047 * @author <a href="raphael@apache.org">Raphaƫl Luta</a> 048 * @version $Id: TemplateScreen.java 1709648 2015-10-20 17:08:10Z tv $ 049 */ 050public class TemplateScreen 051{ 052 /** Logging */ 053 private static Log log = LogFactory.getLog(TemplateScreen.class); 054 055 /* The RunData object. */ 056 private final RunData data; 057 058 /* The name of the screen template. */ 059 private String screen; 060 061 private final ScreenLoader screenLoader; 062 063 /** 064 * Constructor 065 * 066 * @param data A Turbine RunData object. 067 */ 068 public TemplateScreen(RunData data) 069 { 070 this.data = data; 071 this.screen = data.getScreen(); 072 this.screenLoader = (ScreenLoader)TurbineAssemblerBroker.getLoader(Screen.class); 073 } 074 075 /** 076 * Set the screen. 077 * 078 * @param screen A String with the name of the screen module 079 * @return A TemplateScreen (self). 080 */ 081 public TemplateScreen setScreen(String screen) 082 { 083 this.screen = screen; 084 return this; 085 } 086 087 /** 088 * Builds the output of the navigation template. 089 * 090 * @return A String. 091 */ 092 @Override 093 public String toString() 094 { 095 String returnValue = ""; 096 097 try 098 { 099 String results = screenLoader.eval(data, this.screen); 100 101 if (results != null) 102 { 103 returnValue = results; 104 } 105 } 106 catch (Exception e) 107 { 108 log.error(e); 109 } 110 111 return returnValue; 112 } 113}