WHAT IS THE DIFFERENCES BETWEEN TagSupport and BodyTagSupport. and when to use eath of them give alll possible differences

A BodyTag can manipulate its body, using its BodyContent object, while a normal Tag cannot. BodyTags are useful when you want to use or transform the contents of the tag.

For example, suppose you want to have a <cust:param> tag that sets parameter values using the tag body:

<cus:param name="[param-name]">[param-value]</cust:param>

This would have to be implemented as a BodyTag, which could get the tag contents (and the parameter value) as follows:

public int doAfterBody() {
    String paramValue = bodyContent.getString();
    // More logic ...
}