Custom tag for Marquee in JSF

Question

Hi,
I am trying to develop a custom tag for Marquee in JSF, my usecase is to display a value from managed bean(Dynamically). please find the code below and guide me where i have made mistake
regards
Sandeep
Component class:
package customtags;
import javax.el.ValueExpression;
import javax.faces.component.UIComponentBase;
import javax.faces.context.FacesContext;
public class Marquee extends UIComponentBase {
     public static final String COMPONENT_TYPE = "marqueecomp";
     public static final String RENDERER_TYPE = "marqueeRenderer";
     private Object[] _state = null;
     private String value;
     public String getValue() {
          if (null != this.value) {
               return this.value;
          ValueExpression _ve = getValueExpression("value");
          return (_ve != null) ? (String) _ve.getValue(getFacesContext()
                    .getELContext()) : null;
     public void setValue(String marquee) {
          this.value = marquee;
     public String getFamily() {
          // TODO Auto-generated method stub
          return COMPONENT_TYPE;
//     public void encodeBegin(FacesContext context) throws IOException {
//          ResponseWriter writer = context.getResponseWriter();
//          writer.startElement("marquee", this);
//          writer.write(getValue());
//          writer.endElement("marquee");
     public void restoreState(FacesContext context, Object state) {
          this._state = (Object[]) _state;
          super.restoreState(_context, this._state[0]);
          value = (String) this._state[1];
     public Object saveState(FacesContext _context) {
          if (_state == null) {
               _state = new Object[2];
          state[0] = super.saveState(context);
          _state[1] = value;
          return _state;
Tag Class:
package customtags;
import javax.el.ValueExpression;
import javax.faces.component.UIComponent;
import javax.faces.webapp.UIComponentELTag;
public class MarqueeTag extends UIComponentELTag {
     protected ValueExpression marquee;
     public String getComponentType() {
          // TODO Auto-generated method stub
          return Marquee.COMPONENT_TYPE;
     public String getRendererType() {
          // TODO Auto-generated method stub
          return Marquee.RENDERER_TYPE;
     * protected void setProperties(UIComponent component) {
     * super.setProperties(component); Marquee marqComp = (Marquee) component;
     * if (marquee != null) { marqComp.setValue(marquee); } }
     protected void setProperties(UIComponent component) {
          super.setProperties(component);
          Marquee marqComp = null;
          try {
               marqComp = (Marquee) component;
          } catch (ClassCastException cce) {
               throw new IllegalStateException(
                         "Component "
                                   + component.toString()
                                   + " not expected type. Expected: com.foo.Foo. Perhaps you're missing a tag?");
          if (marquee != null) {
               //marqComp.setValueExpression("value", marquee);
               marqComp.setValue("fsdfsdfsdfsdfsd");
     * @return the marquee
     public ValueExpression getMarquee() {
          return marquee;
     * @param marquee
     * the marquee to set
     public void setMarquee(ValueExpression marquee) {
          this.marquee = marquee;
*.tld file*
<?xml version="1.0" encoding="UTF-8"?>
<taglib xmlns="http://java.sun.com/xml/ns/javaee"
     xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
     xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-jsptaglibrary_2_1.xsd"
     version="2.1">
     <tlib-version>1.0</tlib-version>
     <short-name>marqueecomp</short-name>
     <uri>http://tags.org/marquee</uri>
     <tag>
          <name>marqueeTag</name>
<tag-class>customtags.MarqueeTag</tag-class>
<body-content>empty</body-content>
<attribute>
<description><![CDATA[Your description here]]></description>
<name>id</name>
<required>false</required>
<rtexprvalue>true</rtexprvalue>
</attribute>
<attribute>
<description><![CDATA[Your description here]]></description>
<name>value</name>
</attribute>
     </tag>
</taglib>
Renderer class:
package customtags;
import java.io.IOException;
import javax.faces.component.UIComponent;
import javax.faces.context.FacesContext;
import javax.faces.context.ResponseWriter;
import javax.faces.render.Renderer;
public class MarqueeRenderer extends Renderer {
     public void encodeBegin(final FacesContext facesContext,
final UIComponent component) throws IOException {
super.encodeBegin(facesContext, component);
final ResponseWriter writer = facesContext.getResponseWriter();
writer.startElement("DIV", component);
/*String styleClass =
(String)attributes.get(Shuffler.STYLECLASS_ATTRIBUTE_KEY);
writer.writeAttribute("class", styleClass, null);*/
public void encodeEnd(final FacesContext facesContext,
final UIComponent component) throws IOException {
final ResponseWriter writer = facesContext.getResponseWriter();
writer.endElement("DIV");
in Faces-Config:
<component>
          <display-name>marqueecomp</display-name>
          <component-type>marqueecomp</component-type>
          <component-class>customtags.Marquee</component-class>
          <component-extension>
<renderer-type>marqueeRenderer</renderer-type>
</component-extension>
     </component>
     <render-kit>
<renderer>
<component-family>marqueecomp</component-family>
<renderer-type>marqueeRenderer</renderer-type>
<renderer-class>customtags.MarqueeRenderer</renderer-class>
</renderer>
</render-kit>
In class path --->marquee.taglib.xml
<?xml version="1.0"?>
<!DOCTYPE facelet-taglib PUBLIC
"-//Sun Microsystems, Inc.//DTD Facelet Taglib 1.0//EN"
"http://java.sun.com/dtd/facelet-taglib_1_0.dtd">
<facelet-taglib>
<namespace>http://tags.org/marquee</namespace>
<tag>
<tag-name>marqueeTag</tag-name>
<component>
<component-type>marqueecomp</component-type>
<renderer-type>marqueeRenderer</renderer-type>
</component>
</tag>
</facelet-taglib>
*.xhtml file*
<html xmlns="http://www.w3.org/1999/xhtml"
     xmlns:ui="http://java.sun.com/jsf/facelets"
     xmlns:h="http://java.sun.com/jsf/html"
     xmlns:f="http://java.sun.com/jsf/core" xml:lang="en" lang="en"
     xmlns:a4j="http://richfaces.org/a4j"
     xmlns:rich="http://richfaces.org/rich" xmlns:mycomp="http://tags.org/marquee">
<head>
<title>DEBTDOC Home Page</title>
<meta http-equiv="keywords" content="enter,your,keywords,here" />
<meta http-equiv="description"
     content="A short description of this page." />
<meta http-equiv="content-type" content="text/html; charset=UTF-8" />
<link rel="stylesheet" type="text/css" href="../css/common.css"></link>
<script language="javascript" src="../script/common.js"></script>
</head>
<body>
<f:view>
<mycomp:marqueeTag value="hello World"></mycomp:marqueeTag>

Answer 1

There exist the JSTL SQL taglib, but I don't recommend this. It should only be used for quick development and testing. For database connectivity, rather create a data layer with DAO classes which you on its turn just plug in your business layer (with servlets).