javawebparts.taglib.jstags
Class DateDifferenceTag

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

All Implemented Interfaces:

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

public class DateDifferenceTag

extends javax.servlet.jsp.tagext.TagSupport

This class is a custom tag that renders the JWPDateDifference() Javascript function which can be called to determine how many days there are between two dates.

This tag uses the following attributes:

renderScriptTags - true/false - When set to true, the Javascript will be rendered inside a <script> </script> tag pair. When set to false, this will not be done and it is expected that the <jstags:DateDifference/> tag appears inside a <script> </script> tag pair. If this attribute is not present, the script tags WILL be rendered.

It renders the following Javascript:

function JWPDateDifference(inDate1, inDate2) {
return Math.round(Math.abs(inDate1.getTime() - inDate2.getTime()) / 86400000);
}

Usage example:

numDays = JWPDateDifference(new Date(2007,10,12), new Date(2007, 10, 20));
This results in the number of days between the first date and second date (note that the value will always be a positive number, regardless of which date is in the future relative to the other).

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

DateDifferenceTag()

Method Summary

int	doStartTag() Render the results of the tag.
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

DateDifferenceTag

public DateDifferenceTag()

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