获取初始化参数
在web.xml中使用init-param初始化参数
<servlet>
<description>This is the description of my J2EE component</description>
<display-name>This is the display name of my J2EE component</display-name>
<servlet-name>GetInitParameterServlet</servlet-name>
<servlet-class>servlet.GetInitParameterServlet</servlet-class>
<init-param>
<param-name>username</param-name>
<param-value>admin</param-value>
</init-param>
<init-param>
<param-name>password</param-name>
<param-value>123456</param-value>
</init-param>
</servlet>
<servlet-mapping>
<servlet-name>GetInitParameterServlet</servlet-name>
<url-pattern>/servlet/GetInitParameterServlet</url-pattern>
</servlet-mapping>
创建servlet名字为:GetInitParameterServlet
首先在GetInitParameterServlet界面设置变量用来在后面接受从web.xml初始化的值
private String username;//用户名
private String password;//密码
public String getUsername() {
return username;
}
public void setUsername(String username) {
this.username = username;
}
public String getPassword() {
return password;
}
public void setPassword(String password) {
this.password = password;
}
this.getInitParameter("username")
方法获取web.xml初始化的值
this.setUsername(this.getInitParameter(“username”));
在servlet页面获取初始化的值
public void init() throws ServletException {
this.setUsername(this.getInitParameter("username"));
this.setPassword(this.getInitParameter("password"));
将获取的值输出
public void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
response.setContentType("text/html; charset=utf-8");
PrintWriter out = response.getWriter();
out.println("<!DOCTYPE HTML PUBLIC \"-//W3C//DTD HTML 4.01 Transitional//EN\">");
out.println("<HTML>");
out.println(" <HEAD><TITLE>A Servlet</TITLE></HEAD>");
out.println(" <BODY>");
out.print("<h2>"+"用户名:"+this.getUsername()+"</h2>");
out.print("<h2>"+"密码:"+this.getPassword()+"</h2>");
out.println(" </BODY>");
out.println("</HTML>");
out.flush();
out.close();
}