/* * $Header: /cvsroot/jetty/Jetty/src/org/apache/jasper/compiler/BeanGenerator.java,v 1.1 2000/10/09 17:57:40 gregwilkins Exp $ * $Revision: 1.1 $ * $Date: 2000/10/09 17:57:40 $ * The Apache Software License, Version 1.1 * * Copyright (c) 1999 The Apache Software Foundation. All rights * reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in * the documentation and/or other materials provided with the * distribution. * * 3. The end-user documentation included with the redistribution, if * any, must include the following acknowlegement: * "This product includes software developed by the * Apache Software Foundation (http://www.apache.org/)." * Alternately, this acknowlegement may appear in the software itself, * if and wherever such third-party acknowlegements normally appear. * * 4. The names "The Jakarta Project", "Tomcat", and "Apache Software * Foundation" must not be used to endorse or promote products derived * from this software without prior written permission. For written * permission, please contact apache@apache.org. * * 5. Products derived from this software may not be called "Apache" * nor may "Apache" appear in their names without prior written * permission of the Apache Group. * * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE * DISCLAIMED. IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. * ==================================================================== * * This software consists of voluntary contributions made by many * individuals on behalf of the Apache Software Foundation. For more * information on the Apache Software Foundation, please see * . * */ package org.apache.jasper.compiler; import java.util.Hashtable; import java.util.Vector; import java.util.Enumeration; import java.lang.reflect.Method; import org.apache.jasper.JasperException; import org.apache.jasper.Constants; /** * Generate code for useBean. * * @author Mandar Raje */ public class BeanGenerator extends GeneratorBase implements ServiceMethodPhase, ClassDeclarationPhase { Hashtable attrs; BeanRepository beanInfo; boolean genSession; boolean beanRT = false; Mark start; public BeanGenerator (Mark start, Hashtable attrs, BeanRepository beanInfo, boolean genSession) { this.attrs = attrs; this.beanInfo = beanInfo; this.genSession = genSession; this.start = start; } public void generate (ServletWriter writer, Class phase) throws JasperException { if (ClassDeclarationPhase.class.equals (phase)) checkSyntax (writer, phase); else if (ServiceMethodPhase.class.equals (phase)) generateMethod (writer, phase); } public void checkSyntax (ServletWriter writer, Class phase) throws JasperException { String name = getAttribute ("id"); String varname = name; String serfile = name; String scope = getAttribute ("scope"); String clsname = getAttribute ("class"); String type = getAttribute ("type"); String beanName = getAttribute ("beanName"); // Check for mandatory attributes: if ( name == null ) { String m = Constants.getString("jsp.error.usebean.missing.attribute"); throw new CompileException(start, m); } if (clsname == null && type == null) { String m = Constants.getString("jsp.error.usebean.missing.type", new Object[] {name}); throw new CompileException (start, m); } if (beanInfo.checkVariable(name) == true) { String m = Constants.getString("jsp.error.usebean.duplicate", new Object[] {name}); throw new CompileException (start, m); } if (scope != null && scope.equalsIgnoreCase ("session")) { if (genSession != true) { String m = Constants.getString("jsp.error.usebean.prohibited.as.session", new Object[] {name}); throw new CompileException (start, m); } } if (clsname != null && beanName != null) { String m = Constants.getString("jsp.error.usebean.not.both", new Object[] {name}); throw new CompileException (start, m); } if (clsname == null) clsname = type; if (scope == null || scope.equals("page")) { beanInfo.addPageBean(name, clsname); } else if (scope.equals("request")) { beanInfo.addRequestBean(name, clsname); } else if (scope.equals("session")) { beanInfo.addSessionBean(name,clsname); } else if (scope.equals("application")) { beanInfo.addApplicationBean(name,clsname); } else { String m = Constants.getString("jsp.error.usebean.invalid.scope", new Object[] {name, scope}); throw new CompileException (start, m); } } public void generateMethod (ServletWriter writer, Class phase) throws JasperException { String name = getAttribute ("id"); String varname = name; String serfile = name; String scope = getAttribute ("scope"); String clsname = getAttribute ("class"); String type = getAttribute ("type"); String beanName = getAttribute ("beanName"); if (type == null) type = clsname; // See if beanName is a request-time expression. if (beanName != null && JspUtil.isExpression (beanName)) { beanName = JspUtil.getExpr (beanName); beanRT = true; } if (scope == null || scope.equals ("page")) { // declare the variable. declareBean (writer, type, varname); // synchronized inspection. lock (writer, "pageContext"); // Generate code to locate the bean. locateBean (writer, type, varname, name, "PageContext.PAGE_SCOPE"); // create the bean if it doesn't exists. createBean (writer, varname, clsname, beanName, name, type, "PageContext.PAGE_SCOPE"); // unlock unlock (writer); // Initialize the bean if the body is present. generateInit (writer, varname); } else if (scope.equals ("request")) { // declare the variable. declareBean (writer, type, varname); // synchronized inspection. lock (writer, "request"); // Generate code to locate the bean. locateBean (writer, type, varname, name, "PageContext.REQUEST_SCOPE"); // create the bean if it doesn't exists. createBean (writer, varname, clsname, beanName, name, type, "PageContext.REQUEST_SCOPE"); // unlock. unlock (writer); // Initialize the bean if the body is present. generateInit (writer, varname); } else if (scope.equals ("session")) { // declare the variable. declareBean (writer, type, varname); // synchronized inspection. lock (writer, "session"); // Generate code to locate the bean. locateBean (writer, type, varname, name, "PageContext.SESSION_SCOPE"); // create the bean if it doesn't exists. createBean (writer, varname, clsname, beanName, name, type, "PageContext.SESSION_SCOPE"); // unlock. unlock (writer); // Initialize the bean. generateInit (writer, varname); } else if (scope.equals ("application")) { // declare the variable. declareBean (writer, type, varname); // synchronized inspection lock (writer, "application"); // Generate code to locate the bean. locateBean (writer, type, varname, name, "PageContext.APPLICATION_SCOPE"); // create the bean if it doesn't exist. createBean (writer, varname, clsname, beanName, name, type, "PageContext.APPLICATION_SCOPE"); // unlock. unlock (writer); // Initialize the bean. generateInit (writer, varname); } } private void lock (ServletWriter writer, String scope) { writer.println(" synchronized (" + scope + ") {"); writer.pushIndent(); } private void unlock (ServletWriter writer) { writer.popIndent(); writer.println(" } "); } private void generateInit (ServletWriter writer, String name) { writer.println ("if(_jspx_special" + name + " == true) {"); } private void declareBean (ServletWriter writer, String type, String varname) { writer.println (type + " " + varname + " = null;"); // Variable _jspx_special used for initialization. writer.println ("boolean _jspx_special" + varname + " = false;"); } private void locateBean (ServletWriter writer, String type, String varname, String name, String scope) { writer.println (varname + "= (" + type + ")"); writer.println ("pageContext.getAttribute(" + writer.quoteString(name) + "," + scope + ");"); } private void createBean(ServletWriter writer, String varname, String clsname, String beanName, String name, String type, String scope) { // Create the bean only if classname is specified. // Otherwise bean must be located in the scope. if (clsname != null || beanName != null) { writer.println ("if ( "+varname+" == null ) {"); // Code to create the bean: writer.pushIndent (); // Set the boolean var. so that bean can be initialized. writer.println ("_jspx_special" + name + " = true;"); generateBeanCreate (writer, varname, clsname, beanName, type); writer.println("pageContext.setAttribute(" + writer.quoteString(name) + ", " + varname + ", " + scope + ");"); writer.popIndent (); writer.println ("}"); } else { // clsname not specified -- object must be found inside the scope. writer.println ("if (" + varname + " == null) "); writer.println (" throw new java.lang.InstantiationException (\"bean " + varname + " not found within scope \"); "); } } protected void generateBeanCreate (ServletWriter writer, String varname, String clsname, String beanName, String type) { String convert = (clsname == null) ? type : clsname; if (beanName != null) clsname = beanName; writer.println ("try {"); writer.pushIndent (); if (beanRT == false) writer.println(varname+" = ("+ convert + ") Beans.instantiate(this.getClass().getClassLoader(), "+ writer.quoteString(clsname) +");"); else writer.println(varname+" = ("+ convert + ") Beans.instantiate(this.getClass().getClassLoader(), "+ clsname +");"); writer.popIndent (); writer.println ("} catch (Exception exc) {"); writer.pushIndent (); writer.println (" throw new ServletException (\" Cannot create bean of class \"" + "+\"" + clsname + "\");"); writer.popIndent (); writer.println ("}"); } public String getAttribute(String name) { return (attrs != null) ? (String) attrs.get(name) : null; } }