在Servlet中如何如何獲取請求的參數？

 

獲取Servlet初始化參數

　　　　

Servlet初始化參數配置
獲取Servlet初始化參數2-1
<web-app>
<servlet>
<servlet-name>HelloServlet</servlet-name>
<servlet-class>org.jbit.servlet.HelloServlet</servlet-class>
<init-param>
<param-name>initParam</param-name>
<param-value>Hello Servlet</param-value>
</init-param>
</servlet>
<servlet-mapping>
<servlet-name>HelloServlet</servlet-name>
<url-pattern>/HelloServlet</url-pattern>
</servlet-mapping>
</web-app>

 

根據參數名稱進行讀取

public void doGet(HttpServletRequest request,
HttpServletResponse response)
throws ServletException, IOException {
System.out.println("處理請求時,doGet()方法被調用。");
String initParam = getInitParameter("initParam");
System.out.println(initParam);
}

 

 

獲取Servlet上下文參數

 

配置Servlet上下文

<web-app>
<context-param>
<param-name>contextParam</param-name>
<param-value>Hello Servlet</param-value>
</context-param>
<!--省略其他配置-->
</web-app>

 

讀取Servlet上下文

public class HelloServlet extends HttpServlet {
// …省略其他代碼
public void doGet(HttpServletRequest request,
HttpServletResponse response)
throws ServletException, IOException {
System.out.println("處理請求時，doGet()方法被調用。");
String initParam = getInitParameter("initParam");
String contextParam =
this.getServletContext().getInitParameter("contextParam");
System.out.println("Servlet初始化參數" + initParam);
System.out.println("系統初始化參數" + contextParam);
}
}