javaEE EAR-项目类似 onload 或启动方法

Question

可能的重复：
Java EE 企业应用程序：在部署/启动时执行某些操作

有没有一种方法可以为 javaEE Ear 服务器应用程序定义类似加载方法之类的内容。

例如，我在 JBoss EAR 服务器上使用 Hibernate，该服务器在整个应用程序生命周期中需要一个 SessionFactory 实例。

Answer 1

使用 ServletContextListener

@WebListener
public class Config implements ServletContextListener {

    @Override
    public void contextInitialized(ServletContextEvent event) {
        // Do stuff during webapp's startup.
    }

    @Override
    public void contextDestroyed(ServletContextEvent event) {
        // Do stuff during webapp's shutdown.
    }

}

或 过滤器 (如果您有计划的话特别有用实现“视图中打开会话”模式）

@WebFilter("*.xhtml") // Or whatever URL pattern
public class OpenSessionInViewFilter implements Filter {

    @Override
    public void init(FilterConfig config) throws ServletException {
        // Do stuff during filter's init (so, during webapp's startup).
    }

    @Override
    public void doFilter(ServletRequest req, ServletResponse res, FilterChain chain) throws IOException, ServletException {
        // Do stuff during every request on *.xhtml (or whatever URL pattern)
        chain.doFilter(request, response);
    }

    @Override
    public void destroy() {
        // Do stuff during filter's destroy (so, during webapp's shutdown).
    }

}