JSP 面试题与答案

Question: What is difference between custom JSP tags and beans?

Answer: Custom JSP tag is a tag you defined. You define how a tag, its attributes and its body are interpreted, and then group your tags into collections called tag libraries that can be used in any number of JSP files. To use custom JSP tags, you need to define three separate components: 1. the tag handler class that defines the tag's behavior 2. the tag library descriptor file that maps the XML element names to the tag implementations 3. the JSP file that uses the tag library When the first two components are done, you can use the tag by using taglib directive: <%@ taglib uri="xxx.tld" prefix="..." %> Then you are ready to use the tags you defined. Let's say the tag prefix is test: MyJSPTag or JavaBeans are Java utility classes you defined. Beans have a standard format for Java classes. You use tags to declare a bean and use to set value of the bean class and use to get value of the bean class.