【JSP开发】获取web应用的初始化参数

在web.xml文件中配置：

<init-param>
  <param-name>data</param-name>
  <param-value>XXXXX</param-value>
  </init-param>
  
  <init-param>
  <param-name>data1</param-name>
  <param-value>YYYYY</param-value>
  </init-param>
  
  <init-param>
  <param-name>data2</param-name>
  <param-value>ZZZZZ</param-value>
  </init-param>

ServletDemo7.java：

package cn.edu;


import java.io.IOException;
import java.io.PrintWriter;
import java.util.Enumeration;


import javax.servlet.ServletContext;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;


//获取Web应用的初始化参数
public class ServletDemo7 extends HttpServlet {




  public void doGet(HttpServletRequest request, HttpServletResponse response)
      throws ServletException, IOException {
     
    //单个输出全局初始化参数
    String num=this.getServletContext().getInitParameter("data");
    System.out.println(num);
    
    //输出多个全局初始化参数
    Enumeration e = this.getServletContext().getInitParameterNames();
    while(e.hasMoreElements()){
      String name=(String)e.nextElement();
      String value1=this.getServletConfig().getInitParameter(name);
      System.out.println(name+" = "+value1);
    }
  
  }




  public void doPost(HttpServletRequest request, HttpServletResponse response)
      throws ServletException, IOException {
    doGet(request,response);
  }


}

结果：

data=XXXXXX

data1=YYYYYY

data2=ZZZZZZ