Java tutorial
/** * Copyright 2010 Marko Lavikainen * * Licensed 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 net.contextfw.web.application.component; import java.text.MessageFormat; import org.apache.commons.lang.StringEscapeUtils; import com.google.gson.Gson; /** * This class provides the base implementation for calling javascript commands * on web client. * * <p> * <code>Script</code> can be used as a class property or as a return value of a * method. The method or class property must be annotated with * {@link ScriptElement}-annotation to be recognized. * </p> * * <p> * The script is using {@link MessageFormat} as script format. */ public abstract class Script { /** * Returns the javascript to be executed. Arguments can be injected using * {@link MessageFormat} convention. * * @param scriptContext * The context which can be used to get additional data for * script */ public abstract String getScript(ScriptContext scriptContext); /** * Returns the arguments that are injected to javascript. * * @param scriptContext * The context which can be used to get additional data for * script */ public abstract Object[] getArguments(ScriptContext scriptContext); public void build(DOMBuilder b, Gson gson, ScriptContext scriptContext) { Object[] arguments = getArguments(scriptContext); if (arguments == null) { b.text(getScript(scriptContext)); } else { MessageFormat format = new MessageFormat(getScript(scriptContext)); b.text(format.format(getStringParams(gson, arguments))); } } private Object[] getStringParams(Gson gson, Object[] params) { Object[] rv = new Object[params.length]; for (int i = 0; i < params.length; i++) { Object param = params[i]; if (param == null) { rv[i] = "null"; } else if (Boolean.class.isAssignableFrom(param.getClass()) || Number.class.isAssignableFrom(param.getClass())) { rv[i] = StringEscapeUtils.escapeJavaScript(param.toString()); } else { rv[i] = gson.toJson(param); } } return rv; } }