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[转贴]禁止windows自动更新后自动重启

一餐三碗 — Fri, 15 Sep 2006 01:14:00 GMT

注：windows自动更新后每次都会自动重启，真的很傻，没什么不加一个确认选项呢？还好，看到这篇文章。

原文链接：Prevent Windows automatic updates reboot

Another one of those reminder posts: How to prevent the reboot triggered by the Windows automatic update feature.

Disable automatic updates completely. Not recommended.
Change the policy. Recommended.
1. Start - Run - gpedit.msc
2. Local Group Policy - Computer Configuration - Administrative Templates - Windows - Components - Windows Updates
  
  If you do not see the last element, use the context menu on Administrative Templates to add a new template. Pick the wuau.adm template and close the dialogs. Windows Updates should now show up.
3. Activatge "No auto-restart for scheduled Automatic Updates Installations" and/or use a different warning interval.

On XP Home go to or create the following registry key/value HKEY_LOCAL_MACHINE \Software\Policies \Microsoft\Windows \WindowsUpdate\AU\NoAutoRebootWithLoggedOnUsers (Dword) and set it to either 0 (allow reboots) or 1 (disallow reboots).

一餐三碗 2006-09-15 09:14 发表评论

[转载]Ajax based login using Acegi

一餐三碗 — Wed, 23 Aug 2006 03:00:00 GMT

原文链接:

http://www.jroller.com/page/sjivan?entry=ajax_based_login_using_aceci

Ajax based login using Acegi

Acegi is an extremely powerful Spring module for Authentication and Authorization and has almost become a defacto for web based applications built using Spring. Ajax based applications are getting hotter by the day and having a nice inplace Ajax based login page can improve coolness of your app and make it more Web 2.0'ish.

However implementing an Ajax-Acegi based login does require a little extra work because based on the J2EE spec, when a user tries to login, they are redirected back to the login page if the credentials are invalid or redirected to the success page on successful authentication.

一餐三碗 2006-08-23 11:00 发表评论

解决 Hibernate Annotation 的 "no persistent classes found for query class" 问题

一餐三碗 — Fri, 30 Jun 2006 03:04:00 GMT

软件版本:
hibernate-3.2.0.cr2
hibernate-annotations-3.2.0.CR1

IDE:
idea 5.1

以前都是用XDoclet来实现类似Annotation的功能,但是xdoclet的版本更新实在太慢,永远跟不上hibernate的更新速度,导致很多hibernate新的功能xdoclet都没办法支持.还好,jdk5.0有了Annotation,而且hibernate也开始支持Annotation了.

原来以为从xdoclet转到Annotation很简单,没想到还是遇到了问题,先看代码:

1package test;
2
3import org.hibernate.annotations.Entity;
4
5import javax.persistence.Id;
6import java.io.Serializable;
7
8@Entity
9public class Flight implements Serializable{
10  Long id;
11  String name;
12
13  @Id
14  public Long getId(){
15    return id;
16  }
17
18  public void setId(Long id){
19    this.id=id;
20  }
21
22  public String getName(){
23    return name;
24  }
25
26  public void setName(String name){
27    this.name=name;
28  }
29
30  public boolean equals(Object o){
31    if(this==o) return true;
32    if(o==null||getClass()!=o.getClass()) return false;
33
34    final Flight flight=(Flight)o;
35
36    if(id!=null?!id.equals(flight.id):flight.id!=null) return false;
37    if(name!=null?!name.equals(flight.name):flight.name!=null) return false;
38
39    return true;
40  }
41
42  public int hashCode(){
43    int result;
44    result=(id!=null?id.hashCode():0);
45    result=29*result+(name!=null?name.hashCode():0);
46    return result;
47  }
48}
49

看上去没什么问题吧?没想到运行的时候根本跑不起来,老是提示:

     [java] 10:54:55,842  INFO SessionFactoryObjectFactory:82 - Not binding factory to JNDI, no JNDI name configured
     [java] org.hibernate.hql.ast.QuerySyntaxException: Flight is not mapped [from Flight]
     [java]     at org.apache.tools.ant.taskdefs.ExecuteJava.execute(ExecuteJava.java:180)
     [java]     at org.apache.tools.ant.taskdefs.Java.run(Java.java:710)
     [java]     at org.apache.tools.ant.taskdefs.Java.executeJava(Java.java:178)
     [java]     at org.apache.tools.ant.taskdefs.Java.execute(Java.java:84)
     [java]     at org.apache.tools.ant.UnknownElement.execute(UnknownElement.java:275)
     [java]     at org.apache.tools.ant.Task.perform(Task.java:364)
     [java]     at org.apache.tools.ant.Target.execute(Target.java:341)
     [java]     at org.apache.tools.ant.Target.performTasks(Target.java:369)
     [java]     at org.apache.tools.ant.Project.executeSortedTargets(Project.java:1216)
     [java]     at org.apache.tools.ant.Project.executeTarget(Project.java:1185)
     [java]     at org.apache.tools.ant.helper.DefaultExecutor.executeTargets(DefaultExecutor.java:40)
     [java]     at org.apache.tools.ant.Project.executeTargets(Project.java:1068)
     [java]     at org.apache.tools.ant.Main.runBuild(Main.java:668)
     [java]     at org.apache.tools.ant.Main.startAnt(Main.java:187)
     [java]     at org.apache.tools.ant.launch.Launcher.run(Launcher.java:246)
     [java]     at org.apache.tools.ant.launch.Launcher.main(Launcher.java:67)

看了半天看不出有什么问题,最后终于参考hibernate-annotations-3.2.0.CR1里面单元测试的代码才发现是这段代码有问题:

1import org.hibernate.annotations.Entity;
2
3import javax.persistence.Id;
4import java.io.Serializable;
5

要改成:

1import javax.persistence.Id;
2import javax.persistence.Entity;
3import java.io.Serializable;

原来我用idea开发时,在自动完成的时候想当然地选用了org.hibernate.annotations包下面的annotation,而实际上应该使用javax.persistence包下面的annotation.想想看也很有道理:这样一来我们的JAVA bean就不用import hibernate的包了,用的都是标准的java包.

一餐三碗 2006-06-30 11:04 发表评论

[原创]使用Acegi时获取用户信息的几个函数

一餐三碗 — Fri, 03 Mar 2006 08:17:00 GMT

Acegi框架通过ThreadLocal存放用户信息，因此可以通过以下函数获取相关信息：

  /**
   * 取得当前用户名
   * @return
   */
  public static String getUsername(){
    Context context=ContextHolder.getContext();
    if(context!=null){
      if(context instanceof SecureContext){
        SecureContext sc=(SecureContext)context;
        Authentication auth=sc.getAuthentication();
        if(auth!=null){
          Object principal=auth.getPrincipal();
          if(principal instanceof UserDetails) {
            return ((UserDetails)principal).getUsername();
          }else{
            return principal.toString();
          }
        }
      }
    }
    return null;
  }
  /**
   * 取得当前用户密码
   * @return
   */
  public static String getPassword(){
    Context context=ContextHolder.getContext();
    if(context!=null){
      if(context instanceof SecureContext){
        SecureContext sc=(SecureContext)context;
        Authentication auth=sc.getAuthentication();
        if(auth!=null){
          Object principal=auth.getPrincipal();
          if(principal instanceof UserDetails) {
            return ((UserDetails)principal).getPassword();
          }else{
            return null;
          }
        }
      }
    }
    return null;
  }
  /**
   * 取得当前用户ｓｅｓｓｉｏｎ　ｉｄ
   * @return sessionid or null
   */
  public static String getSessionID(){
    Context context=ContextHolder.getContext();
    if(context!=null){
      if(context instanceof SecureContext){
        SecureContext sc=(SecureContext)context;
        Authentication auth=sc.getAuthentication();
        if(auth!=null){
          Object details=auth.getDetails();
          if(details instanceof WebAuthenticationDetails) {
            return ((WebAuthenticationDetails)details).getSessionId();
          }else{
            return null;
          }
        }
      }
    }
    return null;
  }

一餐三碗 2006-03-03 16:17 发表评论

[转载]How to get (almost) 3 GB heap on Windows!

一餐三碗 — Thu, 08 Dec 2005 03:38:00 GMT

介绍如何使用JRockit 5.0 R26突破2G的单进程应用程序应用内存限制(最大能扩大到3.85 GB )

原文:http://dev2dev.bea.com/blog/hstahl/archive/2005/12/how_to_get_almo.html

一餐三碗 2005-12-08 11:38 发表评论