学习JSP2自定义标签的内容,没有使用开发工具,编写了标签类HelloWorldTag.java,标签库定义文件mytaglib.tld,以及使用自定义标签的jsp页面HelloWorldTag.jsp。启动tomcat后,访问HelloWorldTag.jsp页面,报HelloWorldTag cannot be resolved to a type错误,但我之前已经使用javac命令手动编译了标签类HelloWorldTag.java,并将生成的class文件放到了WEB-INF/classes路径下了。
代码:①HelloWorldTag.java
import java.io.*;
import javax.servlet.*;
import javax.servlet.http.*;
import javax.servlet.jsp.*;
import javax.servlet.jsp.tagext.SimpleTagSupport;
public class HelloWorldTag extends SimpleTagSupport {
public void doTag() throws JspException,IOException {
getJspContext().getOut().write("Hello World"+new java.util.Date());
}
}
②mytaglib.tld
<?xml version="1.0" encoding="UTF-8" ?>
<taglib xmlns="http://java.sun.com/xml/ns/j2ee"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://java.sun.com/xml/ns/j2ee http://java.sun.com/xml/ns/j2ee/web-jsptaglibrary_2_0.xsd"
version="2.0">
<description>A tag library exercising SimpleTag handlers.</description>
<tlib-version>1.0</tlib-version>
<short-name>mytaglib</short-name>
<uri>http://www.jjp.org/mytaglib</uri>
<tag>
<name>helloWorld</name>
<tag-class>HelloWorldTag</tag-class>
<body-content>empty</body-content>
</tag>
</taglib>
③HelloWorldTag.jsp
<%@ page contentType="text/html;charset=GBK" language="java" errorPage="" %>
<%@ taglib uri="http://www.jjp.org/mytaglib" prefix="jjp" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<title>自定义标签示例</title>
<head>
<body>
<h3>以下是自定义标签中的内容</h3>
<jjp:helloWorld/>
</body>
</html>