【servlet初始化参数】利用servletConfig接口获取xml中的init-param参数

利用servletConfig接口获取xml中的init-param参数**

1.结果

2.实现代码
web.xml部署

 	<servlet>
        <servlet-name>Exam</servlet-name> //名
        <servlet-class>Servlet.Exam</servlet-class>//地址
        <init-param>//参数1
            <param-name>name</param-name>
            <param-value>fjh</param-value>
        </init-param>
        <init-param>//参数2
            <param-name>number</param-name>
            <param-value>201711111111</param-value>
        </init-param>
        <init-param>//参数3
            <param-name>sex</param-name>
            <param-value>男</param-value>
        </init-param>
 	</servlet>
 	<servlet-mapping>
        <servlet-name>Exam</servlet-name>//名
        <url-pattern>/Exam</url-pattern>//访问地址
    </servlet-mapping>

实现代码：

package Servlet;

import javax.servlet.ServletConfig;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
import java.io.PrintWriter;
import java.text.SimpleDateFormat;
import java.util.Date;

/**
 * @Author JackFan
 * @data 2020/4/13-16:34
 */
public class Exam extends HttpServlet {
    private String name;
    private String sex;
    private String number;
    @Override
    public void init() throws ServletException
    {

        ServletConfig servletConfig=this.getServletConfig();
         name=servletConfig.getInitParameter("name");
         number=servletConfig.getInitParameter("number");
         sex=servletConfig.getInitParameter("sex");
    }

    @Override
    protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
    }

    @Override
    protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        response.setContentType("text/html;charset=utf-8");
        PrintWriter out=response.getWriter();
        out.write("<h3>"+"姓名:"+name+"</h3>");
        out.write("<h3>"+"学号:"+number+"</h3>");
        out.write("<h3>"+"性别:"+sex+"</h3>");
    }
}

注：

1. xml中的/init-param标签参数在servlet标签内；

2. 有两个参数param-name、param-value；

3. 通过ServletConfig servletConfig=this.getServletConfig(“name”);获取参数的值；

4. 有效范围在该servlet内（本例的Exam内）;

5. 显示中文需要设置编码方式：
   response.setContentType(“text/html;charset=utf-8”)。