//flag for the existence of the "context"
boolean hasContext = ctxt.isAttributeSpecified("context");
//names of the temp variables
String urlName = ctxt.getTemporaryVariableName();
String contextName = ctxt.getTemporaryVariableName();
String baseUrlName = ctxt.getTemporaryVariableName();
String resultName = ctxt.getTemporaryVariableName();
String responseName = ctxt.getTemporaryVariableName();
//get context
ctxt.generateJavaSource("String " + contextName + " = null;");
if(hasContext){
ctxt.generateJavaSource(contextName + " = ");
ctxt.generateAttribute("context");
ctxt.generateJavaSource(";");
}
//get the url
ctxt.generateJavaSource("String " + urlName + " = ");
ctxt.generateAttribute("url");
ctxt.generateJavaSource(";");
//get the raw url according to "url" and "context"
ctxt.generateJavaSource("String " + baseUrlName + " = " +
"org.apache.jasper.tagplugins.jstl.Util.resolveUrl(" + urlName + ", " + contextName + ", pageContext);");
ctxt.generateJavaSource("pageContext.setAttribute" +
"(\"url_without_param\", " + baseUrlName + ");");
//add params
ctxt.generateBody();
ctxt.generateJavaSource("String " + resultName + " = " +
"(String)pageContext.getAttribute(\"url_without_param\");");
ctxt.generateJavaSource("pageContext.removeAttribute" +
"(\"url_without_param\");");
//get the response object
ctxt.generateJavaSource("HttpServletResponse " + responseName + " = " +
"((HttpServletResponse) pageContext.getResponse());");
//if the url is relative, encode it
ctxt.generateJavaSource("if(!org.apache.jasper.tagplugins.jstl.Util.isAbsoluteUrl(" + resultName + ")){");
ctxt.generateJavaSource(" " + resultName + " = "
+ responseName + ".encodeRedirectURL(" + resultName + ");");
ctxt.generateJavaSource("}");
//do redirect
ctxt.generateJavaSource("try{");
ctxt.generateJavaSource(" " + responseName + ".sendRedirect(" + resultName + ");");
ctxt.generateJavaSource("}catch(java.io.IOException ex){");
ctxt.generateJavaSource(" throw new JspTagException(ex.toString(), ex);");
ctxt.generateJavaSource("}");
