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前端學習--015--ServletContext對象實戰學習

目前就這樣撸撸吧!

類代碼(同之前一樣的操作···········23333333333333)

package com.pzhu.servlet;

import java.io.IOException;
import java.io.InputStream;

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

public class ServletContextServlet2 extends HttpServlet {
  @Override
  protected void service(HttpServletRequest req, HttpServletResponse resp)
      throws ServletException, IOException {
    //擷取ServletContext對象
      //第一種方式:
      ServletContext sc=this.getServletContext();
      //第二種方式:
      ServletContext sc2=this.getServletConfig().getServletContext();
      //第三種方式:
      ServletContext sc3=req.getSession().getServletContext();
      System.out.println(sc==sc2);
      System.out.println(sc==sc3);
    //使用ServletContext對象完成資料共享
      //資料存儲
      sc.setAttribute("str", "ServletContext對象學習");
    //擷取項目web.xml的全局配置資料
      String str = sc.getInitParameter("name2");
      System.out.println("全局配置參數:"+str);
    //擷取項目根目錄下的資源的絕對路徑
      //String path="D:\\apache-tomcat-7.0.56\\webapps\\sc\\doc\\1.txt";
      String path=sc.getRealPath("/doc/1.txt");
      System.out.println(path);
    //擷取項目根目錄下資源的流對象
      InputStream is = sc.getResourceAsStream("/doc/1.txt");
  
  }
}      

web.xml配置:

<?xml  version="1.0"  encoding="UTF-8"?>
<web-app  xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns="http://java.sun.com/xml/ns/javaee"
xsi:schemaLocation="http://java.sun.com/xml/ns/javaee
http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd"  id="WebApp_ID"
version="2.5">
<servlet>
<servlet-name>ServletContextServlet2</servlet-name>
<servlet-class>com.pzhu.servlet.ServletContextServlet2</servlet-class>
</servlet>
<servlet-mapping>
<servlet-name>ServletContextServlet2</servlet-name>
<url-pattern>/scs</url-pattern>
</servlet-mapping>
</web-app>      

結果:

前端學習--015--ServletContext對象實戰學習

主人,有沒有一頭霧水呢?2323332323232---------小妲己··············