tag file

This code fragment can be reduced back to a single line by moving the JSTL code into a reusable tag file that outputs the element.

The length. tag file (shown in Listing 12) is another validator that verifies the length of a request parameter.

The tag file defines two attributes: the name of the required field and an optional error message.

This section presents the JSP tag file that generates the JavaScript functions implementing the client-side portion of the RPC mechanism.

The Web page shown in Listing 5 declares the df prefix for the JSP library containing the tag file.

You can limit the number of exported objects to decrease the size of the tag file.

The tag file accepts five attributes: the element's name, the minimum and maximum lengths, and two optional error messages.

Before generating the element, the option. tag file (shown in Listing 16) sets the optionLabel and optionValue variables.

After that, the xhr. tag file starts generating the JavaScript code.

The noCache. tag file (see Listing 11) contains a single line of Java code that sets the Cache-Control header of the HTTP response.

Tag file source is compiled when the including JSP is processed by javac.

If the array attribute is false, the isSelected. tag file compares the value attribute with formModel[name].

The invoke. tag file (see Listing 11) defines a method attribute of type javax. el. MethodExpression.

The variable's name is obtained from the JSP context because it is passed to the tag file as a JSP attribute.

The following example uses the set. tag file to build an input component.

This allows the JSP page to show the validation error before the element that is generated by the tag file.

Using a tag file to produce JavaScript code