javawebparts.taglib.jstags
Class JSDigesterTag

java.lang.Object
  |
  +--javax.servlet.jsp.tagext.TagSupport
        |
        +--javawebparts.taglib.jstags.JSDigesterTag

All Implemented Interfaces:

javax.servlet.jsp.tagext.IterationTag, java.io.Serializable, javax.servlet.jsp.tagext.Tag

public class JSDigesterTag

extends javax.servlet.jsp.tagext.TagSupport

This class is a custom tag that renders the JSDigester. This is a client-side implementation of the Commons Digester component, quite a bit trimmed down though (i.e., only a few of the most common rules are implemented).

JSDigester uses the SAXParser code from the Mozilla JSLib library. It is included here for convenience, with some minor changes required to work for JSDigester, and also to save some space.

The implemented rules are CreateObject, SetProperties, BeanPropertySetter and SetNext. Here is a usage example:

function testJSDigester() { sampleXML = "<movies numMovies=\"2\">\n";
sampleXML += " <movie>\n";
sampleXML += " <title>Star Wars</title>\n";
sampleXML += " <actor gender=\"male\">Harrison Ford< /actor>\n";
sampleXML += " <actor gender=\"female\"> Carrie Fisher</actor>\n";
sampleXML += " </movie>\n";
sampleXML += " <movie>\n";
sampleXML += " <title>Real Genius</title>\n";
sampleXML += " <actor gender=\"male\">Val Kilmer< /actor>\n";
sampleXML += " </movie>\n";
sampleXML += "</movies>";
jsDigester = new JSDigester();
jsDigester.addObjectCreate("movies", "Movies");
jsDigester.addSetProperties("movies");
jsDigester.addObjectCreate("movies/movie", "Movie");
jsDigester.addBeanPropertySetter("movies/movie/title", "setTitle");
jsDigester.addObjectCreate("movies/movie/actor", "Actor");
jsDigester.addSetProperties("movies/movie/actor");
jsDigester.addBeanPropertySetter("movies/movie/actor", "setName");
jsDigester.addSetNext("movies/movie/actor", "addActor");
jsDigester.addSetNext("movies/movie", "addMovie");
myMovies = jsDigester.parse(sampleXML);
}


(This is directly from the sample app. This makes use of some custom Javascript "classes", so please see the sample app for full details)

Because the rendered code is considerably bigger than most of the other tags in the JSTags library, it is not shown here.

Author:

Frank W. Zammetti.

See Also:

Serialized Form

Field Summary

private static org.apache.commons.logging.Log	log Log instance.
private java.lang.String	renderScriptTags Whether to render the opening and closing script tags around the emitted Javascript.

Fields inherited from class javax.servlet.jsp.tagext.TagSupport

id, pageContext

Fields inherited from interface javax.servlet.jsp.tagext.IterationTag

EVAL_BODY_AGAIN

Fields inherited from interface javax.servlet.jsp.tagext.Tag

EVAL_BODY_INCLUDE, EVAL_PAGE, SKIP_BODY, SKIP_PAGE

Constructor Summary

JSDigesterTag()

Method Summary

int	doStartTag() Render the results of the tag.
private void	renderJSDigester(java.lang.StringBuffer sb) Renders the JSDigester class code.
private void	renderRules(java.lang.StringBuffer sb) Renders the Digester rule classes.
private void	renderSAXParser(java.lang.StringBuffer sb) Renders the SAXParser handler class code.
void	setRenderScriptTags(java.lang.String inRenderScriptTags) renderScriptTags mutator.

Methods inherited from class javax.servlet.jsp.tagext.TagSupport

doAfterBody, doEndTag, findAncestorWithClass, getId, getParent, getValue, getValues, release, removeValue, setId, setPageContext, setParent, setValue

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

log

private static org.apache.commons.logging.Log log

Log instance.

renderScriptTags

private java.lang.String renderScriptTags

Whether to render the opening and closing script tags around the emitted Javascript.

Constructor Detail

JSDigesterTag

public JSDigesterTag()

Method Detail

setRenderScriptTags

public void setRenderScriptTags(java.lang.String inRenderScriptTags)

renderScriptTags mutator.

Parameters:

inRenderScriptTags - renderScriptTags.

doStartTag

public int doStartTag()
               throws javax.servlet.jsp.JspException

Render the results of the tag.

Specified by:

doStartTag in interface javax.servlet.jsp.tagext.Tag

Overrides:

doStartTag in class javax.servlet.jsp.tagext.TagSupport

Returns:

Return code.

Throws:

javax.servlet.jsp.JspException - If anything goes wrong

renderSAXParser

private void renderSAXParser(java.lang.StringBuffer sb)

Renders the SAXParser handler class code.

Parameters:

sb - StringBuffer the output is being built up in.

renderJSDigester

private void renderJSDigester(java.lang.StringBuffer sb)

Renders the JSDigester class code.

Parameters:

sb - StringBuffer the output is being built up in.

renderRules

private void renderRules(java.lang.StringBuffer sb)

Renders the Digester rule classes.

Parameters:

sb - StringBuffer the output is being built up in.