问题描述
我有这段代码，
@WebServlet(value="/initializeResources", loadOnStartup=1)
public class InitializeResources extends HttpServlet {
@Override
protected void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
System.out.println("HEREEEE");
}
}
但是servlet无法启动当Web应用程序启动时。
But the servlet doesn't start when the web application is started.
如何在Servlet Annotation上启动加载？
How use load on startup on Servlet Annotation?
我的Servlet API是3.0和我使用Tomcat 7
My Servlet API is 3.0 and I use Tomcat 7
推荐答案
使用当前代码，您需要执行GET请求以查看输出 HEREEEE 。
With you current code, you need to do a GET request for see the output HEREEEE.
如果你想在servlet的启动时做一些事情（即元素值大于或等于零， 0 ），您需要将代码放在init方法或servlet的构造函数中：
If you want to do something on the startup of the servlet (i.e. the element loadOnStartup with value greater or equal to zero, 0), you need put the code in a init method or in the constructor of the servlet:
@Override
public void init() throws ServletException {
System.out.println("HEREEEE");
}
可能更方便使用侦听器在应用程序范围中启动资源（在 ServletContext 中）。
It may be more convenient to use a listener to start a resource in the application scope (in the ServletContext).
import javax.servlet.ServletContextEvent;
import javax.servlet.ServletContextListener;
import javax.servlet.annotation.WebListener;
@WebListener
public class InitializeListener implements ServletContextListener {
@Override
public void contextInitialized(ServletContextEvent sce) {
System.out.println("On start web app");
}
@Override
public void contextDestroyed(ServletContextEvent sce) {
System.out.println("On shutdown web app");
}
}
例如，请参阅我的回答对于的问题。
For an example, see my answer for the question Share variables between JAX-RS requests.
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