generator.java

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                        }
                    }
                }

                visitBody(n);
            }
        }

        page.visit(new ScriptingVarVisitor());
    }

    /**
     * Generates the _jspInit() method for instantiating the tag handler pools.
     * For tag file, _jspInit has to be invoked manually, and the ServletConfig
     * object explicitly passed.
     */
    private void generateInit() {

        if (ctxt.isTagFile()) {
            out.printil("private void _jspInit(ServletConfig config) {");
        } else {
            out.printil("public void _jspInit() {");
        }

        out.pushIndent();
        for (int i = 0; i < tagHandlerPoolNames.size(); i++) {
            out.printin((String)tagHandlerPoolNames.elementAt(i));
            out.print(
                " = org.apache.jasper.runtime.TagHandlerPool.getTagHandlerPool(");
            if (ctxt.isTagFile()) {
                out.print("config");
            } else {
                out.print("getServletConfig()");
            }
            out.println(");");
        }
        out.popIndent();
        out.printil("}");
        out.println();
    }

    /**
     * Generates the _jspDestroy() method which is responsible for calling the
     * release() method on every tag handler in any of the tag handler pools.
     */
    private void generateDestroy() {

        out.printil("public void _jspDestroy() {");
        out.pushIndent();
        for (int i = 0; i < tagHandlerPoolNames.size(); i++) {
            out.printin((String)tagHandlerPoolNames.elementAt(i));
            out.println(".release();");
        }
        out.popIndent();
        out.printil("}");
        out.println();
    }

    /**
     * Generate preamble package name
     * (shared by servlet and tag handler preamble generation)
     */
    private void genPreamblePackage(String packageName)
        throws JasperException {
        if (!"".equals(packageName) && packageName != null) {
            out.printil("package " + packageName + ";");
            out.println();
        }
    }

    /**
     * Generate preamble imports
     * (shared by servlet and tag handler preamble generation)
     */
    private void genPreambleImports() throws JasperException {
        Iterator iter = pageInfo.getImports().iterator();
        while (iter.hasNext()) {
            out.printin("import ");
            out.print((String)iter.next());
            out.println(";");
        }
        out.println();
    }

    /**
     * Generation of static initializers in preamble.
     * For example, dependant list, el function map, prefix map.
     * (shared by servlet and tag handler preamble generation)
     */
    private void genPreambleStaticInitializers() throws JasperException {
        // Static data for getDependants()
        out.printil("private static java.util.List _jspx_dependants;");
        out.println();
        List dependants = pageInfo.getDependants();
        Iterator iter = dependants.iterator();
        if (!dependants.isEmpty()) {
            out.printil("static {");
            out.pushIndent();
            out.printin("_jspx_dependants = new java.util.ArrayList(");
            out.print("" + dependants.size());
            out.println(");");
            while (iter.hasNext()) {
                out.printin("_jspx_dependants.add(\"");
                out.print((String)iter.next());
                out.println("\");");
            }
            out.popIndent();
            out.printil("}");
            out.println();
        }
    }

    /**
     * Declare tag handler pools (tags of the same type and with the same
     * attribute set share the same tag handler pool)
     * (shared by servlet and tag handler preamble generation)
     */
    private void genPreambleClassVariableDeclarations(String className)
        throws JasperException {
        if (isPoolingEnabled && !tagHandlerPoolNames.isEmpty()) {
            for (int i = 0; i < tagHandlerPoolNames.size(); i++) {
                out.printil(
                    "private org.apache.jasper.runtime.TagHandlerPool "
                        + tagHandlerPoolNames.elementAt(i)
                        + ";");
            }
            out.println();
        }
    }

    /**
     * Declare general-purpose methods
     * (shared by servlet and tag handler preamble generation)
     */
    private void genPreambleMethods() throws JasperException {
        // Method used to get compile time file dependencies
        out.printil("public Object getDependants() {");
        out.pushIndent();
        out.printil("return _jspx_dependants;");
        out.popIndent();
        out.printil("}");
        out.println();

        if (isPoolingEnabled && !tagHandlerPoolNames.isEmpty()) {
            generateInit();
            generateDestroy();
        }
    }

    /**
     * Generates the beginning of the static portion of the servlet.
     */
    private void generatePreamble(Node.Nodes page) throws JasperException {

        String servletPackageName = ctxt.getServletPackageName();
        String servletClassName = ctxt.getServletClassName();
        String serviceMethodName = Constants.SERVICE_METHOD_NAME;

        // First the package name:
        genPreamblePackage(servletPackageName);

        // Generate imports
        genPreambleImports();

        // Generate class declaration
        out.printin("public final class ");
        out.print(servletClassName);
        out.print(" extends ");
        out.println(pageInfo.getExtends());
        out.printin(
            "    implements org.apache.jasper.runtime.JspSourceDependent");
        if (!pageInfo.isThreadSafe()) {
            out.println(",");
            out.printin("                 SingleThreadModel");
        }
        out.println(" {");
        out.pushIndent();

        // Class body begins here
        generateDeclarations(page);

        // Static initializations here
        genPreambleStaticInitializers();

        // Class variable declarations
        genPreambleClassVariableDeclarations(servletClassName);

        // Constructor
        //  generateConstructor(className);

        // Methods here
        genPreambleMethods();

        // Now the service method
        out.printin("public void ");
        out.print(serviceMethodName);
        out.println(
            "(HttpServletRequest request, HttpServletResponse response)");
        out.println("        throws java.io.IOException, ServletException {");

        out.pushIndent();
        out.println();

        // Local variable declarations
        out.printil("JspFactory _jspxFactory = null;");
        out.printil("PageContext pageContext = null;");
        if (pageInfo.isSession())
            out.printil("HttpSession session = null;");

        if (pageInfo.isErrorPage()) {
            out.printil(
                "Throwable exception = org.apache.jasper.runtime.JspRuntimeLibrary.getThrowable(request);");
            out.printil("if (exception != null) {");
            out.pushIndent();
            out.printil(
                "response.setStatus(HttpServletResponse.SC_INTERNAL_SERVER_ERROR);");
            out.popIndent();
            out.printil("}");
        }

        out.printil("ServletContext application = null;");
        out.printil("ServletConfig config = null;");
        out.printil("JspWriter out = null;");
        out.printil("Object page = this;");

        out.printil("JspWriter _jspx_out = null;");
        out.printil("PageContext _jspx_page_context = null;");
        out.println();

        declareTemporaryScriptingVars(page);
        out.println();

        out.printil("try {");
        out.pushIndent();

        out.printil("_jspxFactory = JspFactory.getDefaultFactory();");

        out.printin("response.setContentType(");
        out.print(quote(pageInfo.getContentType()));
        out.println(");");

        if (ctxt.getOptions().isXpoweredBy()) {
            out.printil("response.addHeader(\"X-Powered-By\", \"JSP/2.0\");");
        }

        out.printil(
            "pageContext = _jspxFactory.getPageContext(this, request, response,");
        out.printin("\t\t\t");
        out.print(quote(pageInfo.getErrorPage()));
        out.print(", " + pageInfo.isSession());
        out.print(", " + pageInfo.getBuffer());
        out.print(", " + pageInfo.isAutoFlush());
        out.println(");");
        out.printil("_jspx_page_context = pageContext;");

        out.printil("application = pageContext.getServletContext();");
        out.printil("config = pageContext.getServletConfig();");

        if (pageInfo.isSession())
            out.printil("session = pageContext.getSession();");
        out.printil("out = pageContext.getOut();");
        out.printil("_jspx_out = out;");
        out.println();
    }

    /**
     * Generates an XML Prolog, which includes an XML declaration and
     * an XML doctype declaration.
     */
    private void generateXmlProlog(Node.Nodes page) {

        /*
         * An XML declaration is generated under the following conditions:
         *
         * - 'omit-xml-declaration' attribute of <jsp:output> action is set to
         *   "no" or "false"
         * - JSP document without a <jsp:root>
         */
        String omitXmlDecl = pageInfo.getOmitXmlDecl();
        if ((omitXmlDecl != null && !JspUtil.booleanValue(omitXmlDecl))
            || (omitXmlDecl == null
                && page.getRoot().isXmlSyntax()
                && !pageInfo.hasJspRoot()
                && !ctxt.isTagFile())) {
            String cType = pageInfo.getContentType();
            String charSet = cType.substring(cType.indexOf("charset=") + 8);
            out.printil(
                "out.write(\"<?xml version=\\\"1.0\\\" encoding=\\\""
                    + charSet
                    + "\\\"?>\\n\");");
        }

        /*
         * Output a DOCTYPE declaration if the doctype-root-element appears.
         * If doctype-public appears:
         *     <!DOCTYPE name PUBLIC "doctypePublic" "doctypeSystem">
         * else
         *     <!DOCTYPE name SYSTEM "doctypeSystem" >
         */

        String doctypeName = pageInfo.getDoctypeName();
        if (doctypeName != null) {
            String doctypePublic = pageInfo.getDoctypePublic();
            String doctypeSystem = pageInfo.getDoctypeSystem();
            out.printin("out.write(\"<!DOCTYPE ");
            out.print(doctypeName);
            if (doctypePublic == null) {
                out.print(" SYSTEM \\\"");
            } else {
                out.print(" PUBLIC \\\"");
                out.print(doctypePublic);
                out.print("\\\" \\\"");
            }
            out.print(doctypeSystem);
            out.println("\\\">\\n\");");
        }
    }

    /*
     * Generates the constructor.
     * (shared by servlet and tag handler preamble generation)
     */
    private void generateConstructor(String className) {
        out.printil("public " + className + "() {");
        out.printil("}");
        out.println();
    }

    /**
     * A visitor that generates codes for the elements in the page.
     */
    class GenerateVisitor extends Node.Visitor {

        /*
         * Hashtable containing introspection information on tag handlers:
         *   <key>: tag prefix
         *   <value>: hashtable containing introspection on tag handlers:
         *              <key>: tag short name
         *              <value>: introspection info of tag handler for