why Java declared serialVersionUID in Exception and Throwable class?

when I created one custom exception class just like below public class MyApppException extends Exception { private String message = null; public MyApppException() { super(); } public MyApppException(String message) { super(message); this.message = message; } public MyApppException(Throwable cause) { super(cause); } } compiler giving

为什么Java在Exception和Throwable类中声明serialVersionUID?

当我创建一个自定义异常类就像下面 public class MyApppException extends Exception { private String message = null; public MyApppException() { super(); } public MyApppException(String message) { super(message); this.message = message; } public MyApppException(Throwable cause) { super(cause); } } 编译器让我下降 可序列化类InsufficientB

serialVersionUID field warning in eclipse

I have just started on AWT and made a simple program in it, it works fine but it shows a warning message in eclipse which i don't understand: The serializable class TestGUI does not declare a static final serialVersionUID field of type long I know that the warning message is not related to AWT and there was no need to post my whole code but when i tried to make a SSCCE of the code the war

eclipse中的serialVersionUID字段警告

我刚刚开始使用AWT,并在其中制作了一个简单的程序,它工作正常,但它在eclipse中显示了一条警告消息,我不明白: 可序列化类TestGUI不声明long类型的静态final serialVersionUID字段 我知道警告信息与AWT无关,并且不需要发布我的整个代码,但是当我尝试创建代码的SSCCE时,警告也消失了。 由于我不知道为什么会产生这个警告,我不知道在我的SSCCE中保留哪个部分。 因此整个代码! 我的代码是: import java.awt.Frame;

Quartz Scheduler in Web application

I am learning quartz and Have tried some samples which works in Console application. Now am trying in web aplications. Following is what I did. web.xml <?xml version="1.0" encoding="UTF-8"?> <web-app> <servlet> <servlet-name>QuartzInitializer</servlet-name> <display-name> Quartz Initializer Servlet</display-name> <servlet-class>

Quartz Scheduler在Web应用程序中

我正在学习石英,并尝试了一些适用于控制台应用程序的示例。 现在我正在尝试在网络应用程序。 以下是我所做的。 web.xml中 <?xml version="1.0" encoding="UTF-8"?> <web-app> <servlet> <servlet-name>QuartzInitializer</servlet-name> <display-name> Quartz Initializer Servlet</display-name> <servlet-class>org.quartz.ee.servlet.QuartzInitiali

Where do we put the Servlets in the directory structure of Tomcat?

I copied a HelloServlet application i got from the web and put it in the ROOT folder. I ran the server and it doesn't work. What is wrong? I think its about the location of the Java classes. this documentation should help you http://tomcat.apache.org/tomcat-7.0-doc/appdev/deployment.html /WEB-INF/classes/ - This directory contains any Java class files (and associated resources) requi

我们将Servlets放在Tomcat的目录结构中?

我复制了一个从Web获得的HelloServlet应用程序,并将其放入ROOT文件夹中。 我运行了服务器,它不起作用。 哪里不对? 我认为它关于Java类的位置。 这个文档应该可以帮助你 http://tomcat.apache.org/tomcat-7.0-doc/appdev/deployment.html / WEB-INF / classes / - 此目录包含您的应用程序所需的任何Java类文件(和相关资源),包括未组合到JAR文件中的servlet和非servlet类。 如果您的类被组织到Java包中,则必须在/

Generating synthetic social networks?

I have come across a number of social network analysis tools but I was wondering if there are any libraries that let you generate synthetic social networks like the Watts and Strogatz model or the Barabási-Albert Scale-Free networks or a network dependent on the Caveman model. Whatever I have come across are either pure algorithms or implementations in Fortran which is not really my language of

生成综合社交网络?

我遇到了许多社交网络分析工具,但我想知道是否有任何库可以生成合成社交网络,如Watts和Strogatz模型或Barabási-Albert无标度网络或依赖Caveman模型的网络。 无论我遇到的是Fortran中的纯算法还是实现,这都不是我的专业知识。 我目前正在寻找的是一种设置社交网络属性的方法,并且能够生成一个综合网络(也许是邻接列表)以供进一步分析。 有没有人有什么建议? Python的networkx软件包有许多随机图形生成方法。 igraph

Java: Hibernate does not see changes in DataBase

I have two different applications that share the same database. The problem is that when I have an application change something in the database, the other does not update. I tried to make a session.flush() but it didn't work. The only way is to close the entire session and recreate it, but of course, that takes too long. Short answer: issue a session.refresh(obj) every time you want to

Java:Hibernate在DataBase中看不到变化

我有两个不同的应用程序共享相同的数据库。 问题是,当我有一个应用程序更改数据库中的某些内容时,另一个不会更新。 我试图做一个session.flush()但它没有奏效。 唯一的办法是关闭整个会话并重新创建它,但当然这需要很长时间。 简短的回答:每次你想显示一些对象时,发出session.refresh(obj) 。 它会迫使Hibernate去数据库。 另一种解决方案是使用StatelessSession ,它不会缓存任何内容(甚至不是第一级缓存),每次

RESTful Authentication via Spring

Problem: We have a Spring MVC-based RESTful API which contains sensitive information. The API should be secured, however sending the user's credentials (user/pass combo) with each request is not desirable. Per REST guidelines (and internal business requirements), the server must remain stateless. The API will be consumed by another server in a mashup-style approach. Requirements: Cli

通过Spring进行RESTful认证

问题: 我们有一个基于Spring MVC的RESTful API,其中包含敏感信息。 API应该是安全的,但是发送用户凭据(用户/传递组合)与每个请求是不可取的。 根据REST准则(和内部业务要求),服务器必须保持无状态。 该API将以混搭风格的方式被另一台服务器使用。 要求: 客户端使用凭证发出.../authenticate (未受保护的URL)的请求; 服务器返回一个安全令牌,其中包含足够的信息供服务器验证未来请求并保持无状态。 这可能

Proxy HTTP digest authentication request to LDAP server

Recently we've been working on a project that integrates our Tomcat web server with a couple specific services on a mobile device. One of the things we can do during our interaction with the device (which is over HTTP) is get the device to prompt the user for credentials. After the user has entered their credentials, our server receives an HTTP post that contains the standard HTTP digest au

代理HTTP摘要认证请求到LDAP服务器

最近我们一直在研究一个项目,该项目将我们的Tomcat Web服务器与移动设备上的几项特定服务集成在一起。 我们在与设备进行交互(通过HTTP)过程中可以做的一件事就是让设备提示用户输入凭据。 在用户输入他们的凭证后,我们的服务器会收到一个包含标准HTTP摘要验证头的HTTP帖子(包含nonce,领域,响应等的授权头)。 那里没有什么大的惊喜。 我们的服务器(按设计)实际上并不包含任何用户的密码。 我们保留其密码的SHA512

Using content type application/x

I want to upload a file using java client to server where content type should be application/x-www-form-urlencoded . Using java.net.URLConnection to fire and handle HTTP requests has nice explanation on how to use application/x-www-form-urlencoded but I coudn't find a way to upload file using this . Are there any hints to do this? (Don't suggest to use multipart/form-data)

使用内容类型application / x

我想用java客户端上传一个文件到服务器,其中内容类型应该是application / x-www-form-urlencoded。 使用java.net.URLConnection来触发和处理HTTP请求对如何使用application / x-www-form-urlencoded有很好的解释,但是我没有找到使用这种方法上传文件的方法。 有没有提示要做到这一点? (不建议使用multipart / form-data)

International characters in filename in mutipart formdata

I am using Apache HTTP components (4.1-alpha2) to upload a files to dropbox. This is done using multipart form data. What is the correct way to encode filenames in in a multipart form that contain international (non-ascii) characters? If I use there standard API, the server returns an HTTP status Forbidden. If I modify the upload code so the file name is urlencoded: MultipartEntity entity =

文件名中的国际字符以多部分形式提供

我使用Apache HTTP组件(4.1-alpha2)将文件上传到Dropbox。 这是使用多部分表单数据完成的。 以包含国际(非ascii)字符的多部分形式对文件名进行编码的正确方法是什么? 如果我使用标准API,服务器将返回一个HTTP状态Forbidden。 如果我修改上传代码,以便文件名为urlencoded: MultipartEntity entity = new MultipartEntity(HttpMultipartMode.BROWSER_COMPATIBLE); FileBody bin = new FileBody(file_obj, URLEncoder.