从包装VaadinSession中提取后,可以将标准Servlet会话的超时设置为整数秒的int数.

VaadinSession.getCurrent().getSession().setMaxInactiveInterval ( ( int ) TimeUnit.MINUTES.toSeconds( 30 ) ) ;

以编程方式设置会话超时

设置session超时是web container(Servlet引擎)中的一项功能,例如Tomcat,Jetty等.Servlet规范为Java应用程序定义了此行为,作为其会话处理的一部分.

Vaadin将Servlet会话包装在VaadinSession内.因此,将Vaadin中的常规Servlet会话作为WrappedSession提取,然后调用setMaxInactiveInterval方法设置到期时间.

将时间限制指定为整秒数. TimeUnit枚举可以方便地计算秒数,而无需求助于“magic” numbers.

VaadinSession               // Wraps a standard Servlet session.
.getCurrent()               // Access the current user’s session.
.getSession()               // Access the wrapped standard Servlet session.
.setMaxInactiveInterval(    // Set the timeout.
    ( int )                 // Cast a `long` to an `int`.
    TimeUnit                // The `TimeUnit` enum is more self-documenting than using a literal integer number.
    .MINUTES                // Here we set a half hour,30 minutes.
    .toSeconds( 30 )        // Set a number of whole seconds.      
)
;

以下是从Maven原型vaadin-archetype-application创建的完整示例Vaadin 8.5应用程序.我们在init方法的开头添加了一行.

package com.basilbourque.example;

import javax.servlet.annotation.WebServlet;

import com.vaadin.annotations.Theme;
import com.vaadin.annotations.VaadinServletConfiguration;
import com.vaadin.server.VaadinRequest;
import com.vaadin.server.VaadinServlet;
import com.vaadin.server.VaadinSession;
import com.vaadin.ui.Button;
import com.vaadin.ui.Label;
import com.vaadin.ui.TextField;
import com.vaadin.ui.UI;
import com.vaadin.ui.VerticalLayout;

import java.util.concurrent.TimeUnit;

/**
 * This UI is the application entry point. A UI may either represent a browser window
 * (or tab) or some part of an HTML page where a Vaadin application is embedded.
 *