JSP自定义标签获取用户IP地址的方法
本文导语: 1、编写一个实现tag接口的标签处理器类 代码如下:package cn.itcast.web.tag; import java.io.IOException; import javax.servlet.http.HttpServletRequest;import javax.servlet.jsp.JspException;import javax.servlet.jsp.JspWriter;import javax.servlet.jsp.PageContext;import javax.servlet....
1、编写一个实现tag接口的标签处理器类
package cn.itcast.web.tag;
import java.io.IOException;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.jsp.JspException;
import javax.servlet.jsp.JspWriter;
import javax.servlet.jsp.PageContext;
import javax.servlet.jsp.tagext.Tag;
public class ViewIPTag implements Tag {
private PageContext pageContext;
public int doStartTag() throws JspException {
HttpServletRequest request = (HttpServletRequest) pageContext.getRequest();//获取页面Servlet中 request 和out 对象
JspWriter out = pageContext.getOut();
String ip = request.getRemoteAddr(); //获取用户IP地址
try {
out.write(ip);
} catch (IOException e) {
throw new RuntimeException(e);
}
return 0;
}
public int doEndTag() throws JspException {
return 0;
}
public Tag getParent() {
return null;
}
public void release() {
}
public void setPageContext(PageContext arg0) {
this.pageContext = arg0;//PageContext获取用户request out 等对象
}
public void setParent(Tag arg0) {
}
}
2、在web-inf/目录下新建tld文件,在tld文件中对标签处理器进行描述
A tag library exercising SimpleTag handlers.
1.0
SimpleTagLibrary
/itcast
viewIP
cn.itcast.web.tag.ViewIPTag
empty
3、在jsp页面中导入并使用自定义标签
输出客户机的IP
您的IP是: