| /* |
| * Licensed to the Apache Software Foundation (ASF) under one or more |
| * contributor license agreements. See the NOTICE file distributed with |
| * this work for additional information regarding copyright ownership. |
| * The ASF licenses this file to You 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 org.apache.jasper.tagplugins.jstl.core; |
| |
| import org.apache.jasper.compiler.tagplugin.TagPlugin; |
| import org.apache.jasper.compiler.tagplugin.TagPluginContext; |
| |
| public class Param implements TagPlugin { |
| |
| public void doTag(TagPluginContext ctxt) { |
| |
| //don't support the body content |
| |
| //define names of all the temp variables |
| String nameName = ctxt.getTemporaryVariableName(); |
| String valueName = ctxt.getTemporaryVariableName(); |
| String urlName = ctxt.getTemporaryVariableName(); |
| String encName = ctxt.getTemporaryVariableName(); |
| String index = ctxt.getTemporaryVariableName(); |
| |
| //if the param tag has no parents, throw a exception |
| TagPluginContext parent = ctxt.getParentContext(); |
| if(parent == null){ |
| ctxt.generateJavaSource(" throw new JspTagExcption" + |
| "(\"<param> outside <import> or <urlEncode>\");"); |
| return; |
| } |
| |
| //get the url string before adding this param |
| ctxt.generateJavaSource("String " + urlName + " = " + |
| "(String)pageContext.getAttribute(\"url_without_param\");"); |
| |
| //get the value of "name" |
| ctxt.generateJavaSource("String " + nameName + " = "); |
| ctxt.generateAttribute("name"); |
| ctxt.generateJavaSource(";"); |
| |
| //if the "name" is null then do nothing. |
| //else add such string "name=value" to the url. |
| //and the url should be encoded |
| ctxt.generateJavaSource("if(" + nameName + " != null && !" + nameName + ".equals(\"\")){"); |
| ctxt.generateJavaSource(" String " + valueName + " = "); |
| ctxt.generateAttribute("value"); |
| ctxt.generateJavaSource(";"); |
| ctxt.generateJavaSource(" if(" + valueName + " == null) " + valueName + " = \"\";"); |
| ctxt.generateJavaSource(" String " + encName + " = pageContext.getResponse().getCharacterEncoding();"); |
| ctxt.generateJavaSource(" " + nameName + " = java.net.URLEncoder.encode(" + nameName + ", " + encName + ");"); |
| ctxt.generateJavaSource(" " + valueName + " = java.net.URLEncoder.encode(" + valueName + ", " + encName + ");"); |
| ctxt.generateJavaSource(" int " + index + ";"); |
| ctxt.generateJavaSource(" " + index + " = " + urlName + ".indexOf(\'?\');"); |
| //if the current param is the first one, add a "?" ahead of it |
| //else add a "&" ahead of it |
| ctxt.generateJavaSource(" if(" + index + " == -1){"); |
| ctxt.generateJavaSource(" " + urlName + " = " + urlName + " + \"?\" + " + nameName + " + \"=\" + " + valueName + ";"); |
| ctxt.generateJavaSource(" }else{"); |
| ctxt.generateJavaSource(" " + urlName + " = " + urlName + " + \"&\" + " + nameName + " + \"=\" + " + valueName + ";"); |
| ctxt.generateJavaSource(" }"); |
| ctxt.generateJavaSource(" pageContext.setAttribute(\"url_without_param\"," + urlName + ");"); |
| ctxt.generateJavaSource("}"); |
| } |
| } |