generator.java

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                    // inline, which is only okay if value is not an EL
                    // expression.  Also, key/value pairs for the
                    // embed tag were not being generated correctly.
                    // Double check that this is now the correct behavior.
                    if (ie) {
                        // We want something of the form
                        // out.println( "<PARAM name=\"blah\"
                        //     value=\"" + ... + "\">" );
                        out.printil(
                            "out.write( \"<PARAM name=\\\""
                                + escape(name)
                                + "\\\" value=\\\"\" + "
                                + attributeValue(
                                    n.getValue(),
                                    false,
                                    String.class)
                                + " + \"\\\">\" );");
                        out.printil("out.write(\"\\n\");");
                    } else {
                        // We want something of the form
                        // out.print( " blah=\"" + ... + "\"" );
                        out.printil(
                            "out.write( \" "
                                + escape(name)
                                + "=\\\"\" + "
                                + attributeValue(
                                    n.getValue(),
                                    false,
                                    String.class)
                                + " + \"\\\"\" );");
                    }

                    n.setEndJavaLine(out.getJavaLine());
                }
            }

            String type = n.getTextAttribute("type");
            String code = n.getTextAttribute("code");
            String name = n.getTextAttribute("name");
            Node.JspAttribute height = n.getHeight();
            Node.JspAttribute width = n.getWidth();
            String hspace = n.getTextAttribute("hspace");
            String vspace = n.getTextAttribute("vspace");
            String align = n.getTextAttribute("align");
            String iepluginurl = n.getTextAttribute("iepluginurl");
            String nspluginurl = n.getTextAttribute("nspluginurl");
            String codebase = n.getTextAttribute("codebase");
            String archive = n.getTextAttribute("archive");
            String jreversion = n.getTextAttribute("jreversion");

            String widthStr = null;
            if (width != null) {
                if (width.isNamedAttribute()) {
                    widthStr =
                        generateNamedAttributeValue(
                            width.getNamedAttributeNode());
                } else {
                    widthStr = attributeValue(width, false, String.class);
                }
            }

            String heightStr = null;
            if (height != null) {
                if (height.isNamedAttribute()) {
                    heightStr =
                        generateNamedAttributeValue(
                            height.getNamedAttributeNode());
                } else {
                    heightStr = attributeValue(height, false, String.class);
                }
            }

            if (iepluginurl == null)
                iepluginurl = Constants.IE_PLUGIN_URL;
            if (nspluginurl == null)
                nspluginurl = Constants.NS_PLUGIN_URL;

            n.setBeginJavaLine(out.getJavaLine());

            // If any of the params have their values specified by
            // jsp:attribute, prepare those values first.
            // Look for a params node and prepare its param subelements:
            Node.JspBody jspBody = findJspBody(n);
            if (jspBody != null) {
                Node.Nodes subelements = jspBody.getBody();
                if (subelements != null) {
                    for (int i = 0; i < subelements.size(); i++) {
                        Node m = subelements.getNode(i);
                        if (m instanceof Node.ParamsAction) {
                            prepareParams(m);
                            break;
                        }
                    }
                }
            }

            // XXX - Fixed a bug here - width and height can be set
            // dynamically.  Double-check if this generation is correct.

            // IE style plugin
            // <OBJECT ...>
            // First compose the runtime output string
            String s0 = "<OBJECT"
                    + makeAttr("classid", ctxt.getOptions().getIeClassId())
                    + makeAttr("name", name);

            String s1 = "";
            if (width != null) {
                s1 = " + \" width=\\\"\" + " + widthStr + " + \"\\\"\"";
            }

            String s2 = "";
            if (height != null) {
                s2 = " + \" height=\\\"\" + " + heightStr + " + \"\\\"\"";
            }

            String s3 = makeAttr("hspace", hspace)
                    + makeAttr("vspace", vspace)
                    + makeAttr("align", align)
                    + makeAttr("codebase", iepluginurl)
                    + '>';

            // Then print the output string to the java file
            out.printil(
                "out.write(" + quote(s0) + s1 + s2 + " + " + quote(s3) + ");");
            out.printil("out.write(\"\\n\");");

            // <PARAM > for java_code
            s0 = "<PARAM name=\"java_code\"" + makeAttr("value", code) + '>';
            out.printil("out.write(" + quote(s0) + ");");
            out.printil("out.write(\"\\n\");");

            // <PARAM > for java_codebase
            if (codebase != null) {
                s0 = "<PARAM name=\"java_codebase\""
                        + makeAttr("value", codebase)
                        + '>';
                out.printil("out.write(" + quote(s0) + ");");
                out.printil("out.write(\"\\n\");");
            }

            // <PARAM > for java_archive
            if (archive != null) {
                s0 = "<PARAM name=\"java_archive\""
                        + makeAttr("value", archive)
                        + '>';
                out.printil("out.write(" + quote(s0) + ");");
                out.printil("out.write(\"\\n\");");
            }

            // <PARAM > for type
            s0 = "<PARAM name=\"type\""
                    + makeAttr(
                        "value",
                        "application/x-java-"
                            + type
                            + ";"
                            + ((jreversion == null)
                                ? ""
                                : "version=" + jreversion))
                    + '>';
            out.printil("out.write(" + quote(s0) + ");");
            out.printil("out.write(\"\\n\");");

            /*
             * generate a <PARAM> for each <jsp:param> in the plugin body
             */
            if (n.getBody() != null)
                n.getBody().visit(new ParamVisitor(true));

            /*
             * Netscape style plugin part
             */
            out.printil("out.write(" + quote("<COMMENT>") + ");");
            out.printil("out.write(\"\\n\");");
            s0 = "<EMBED"
                    + makeAttr(
                        "type",
                        "application/x-java-"
                            + type
                            + ";"
                            + ((jreversion == null)
                                ? ""
                                : "version=" + jreversion))
                    + makeAttr("name", name);

            // s1 and s2 are the same as before.

            s3 = makeAttr("hspace", hspace)
                    + makeAttr("vspace", vspace)
                    + makeAttr("align", align)
                    + makeAttr("pluginspage", nspluginurl)
                    + makeAttr("java_code", code)
                    + makeAttr("java_codebase", codebase)
                    + makeAttr("java_archive", archive);
            out.printil(
                "out.write(" + quote(s0) + s1 + s2 + " + " + quote(s3) + ");");

            /*
             * Generate a 'attr = "value"' for each <jsp:param> in plugin body
             */
            if (n.getBody() != null)
                n.getBody().visit(new ParamVisitor(false));

            out.printil("out.write(" + quote("/>") + ");");
            out.printil("out.write(\"\\n\");");

            out.printil("out.write(" + quote("<NOEMBED>") + ");");
            out.printil("out.write(\"\\n\");");

            /*
             * Fallback
             */
            if (n.getBody() != null) {
                visitBody(n);
                out.printil("out.write(\"\\n\");");
            }

            out.printil("out.write(" + quote("</NOEMBED>") + ");");
            out.printil("out.write(\"\\n\");");

            out.printil("out.write(" + quote("</COMMENT>") + ");");
            out.printil("out.write(\"\\n\");");

            out.printil("out.write(" + quote("</OBJECT>") + ");");
            out.printil("out.write(\"\\n\");");

            n.setEndJavaLine(out.getJavaLine());
        }

        public void visit(Node.NamedAttribute n) throws JasperException {
            // Don't visit body of this tag - we already did earlier.
        }

        public void visit(Node.CustomTag n) throws JasperException {

            // Use plugin to generate more efficient code if there is one.
            if (n.useTagPlugin()) {
                generateTagPlugin(n);
                return;
            }

            TagHandlerInfo handlerInfo = getTagHandlerInfo(n);

            // Create variable names
            String baseVar =
                createTagVarName(n.getQName(), n.getPrefix(), n.getLocalName());
            String tagEvalVar = "_jspx_eval_" + baseVar;
            String tagHandlerVar = "_jspx_th_" + baseVar;
            String tagPushBodyCountVar = "_jspx_push_body_count_" + baseVar;

            // If the tag contains no scripting element, generate its codes
            // to a method.
            ServletWriter outSave = null;
            Node.ChildInfo ci = n.getChildInfo();
            if (ci.isScriptless() && !ci.hasScriptingVars()) {
                // The tag handler and its body code can reside in a separate
                // method if it is scriptless and does not have any scripting
                // variable defined.

                String tagMethod = "_jspx_meth_" + baseVar;

                // Generate a call to this method
                out.printin("if (");
                out.print(tagMethod);
                out.print("(");
                if (parent != null) {
                    out.print(parent);
                    out.print(", ");
                }
                out.print("_jspx_page_context");
                if (pushBodyCountVar != null) {
                    out.print(", ");
                    out.print(pushBodyCountVar);
                }
                out.println("))");
                out.pushIndent();
                out.printil((methodNesting > 0) ? "return true;" : "return;");
                out.popIndent();

                // Set up new buffer for the method
                outSave = out;
                /* For fragments, their bodies will be generated in fragment
                   helper classes, and the Java line adjustments will be done
                   there, hence they are set to null here to avoid double
                   adjustments.
                */
                GenBuffer genBuffer =
                    new GenBuffer(n, n.implementsSimpleTag()? null: n.getBody());
                methodsBuffered.add(genBuffer);
                out = genBuffer.getOut();

                methodNesting++;
                // Generate code for method declaration
                out.println();
                out.pushIndent();
                out.printin("private boolean ");
                out.print(tagMethod);
                out.print("(");
                if (parent != null) {
                    out.print("javax.servlet.jsp.tagext.JspTag ");
                    out.print(parent);
                    out.print(", ");
                }
                out.print("PageContext _jspx_page_context");
                if (pushBodyCountVar != null) {
                    out.print(", int[] ");
                    out.print(pushBodyCountVar);
                }
                out.println(")");
                out.printil("        throws Throwable {");
                out.pushIndent();

                // Initilaize local variables used in this method.
                if (! isTagFile) {
                    out.printil("PageContext pageContext = _jspx_page_context;");
                }
                out.printil("JspWriter out = _jspx_page_context.getOut();");
                generateLocalVariables(out, n);
            }

            if (n.implementsSimpleTag()) {
                generateCustomDoTag(n, handlerInfo, tagHandlerVar);
            } else {
                /*
                 * Classic tag handler: Generate code for start element, body,
                 * and end element
                 */
                generateCustomStart(
                    n,
                    handlerInfo,
                    tagHandlerVar,
                    tagEvalVar,
                    tagPushBodyCountVar);

                // visit body
                String tmpParent = parent;
                p