java 服务器重启后的 JSF 问题：找不到保存的视图状态
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JSF problem after server restart: No saved view state could be found
提问by gaffcz
Continue solving this problem, I've replaced Mojarraby MyFacesand upgrade JDK and when I continue working on form after restart of server, following error appears:
继续解决这个问题，我已经更换了钻嘴鱼科通过的MyFaces和升级JDK，当我继续工作形式的服务器重新启动后，显示以下错误：
An Error Occurred:
发生错误：
/food.xhtmlNo saved view state could be found for the view identifier: /food.xhtml
Caused by:
javax.faces.application.ViewExpiredException - /food.xhtmlNo saved view state could be found for the view identifier: /food.xhtml
Console:
控制台：
SEVERE: Exception loading sessions from persistent storage
java.lang.IllegalStateException: unread block data
at java.io.ObjectInputStream$BlockDataInputStream.setBlockDataMode(ObjectInputStream.java:2376)
Stack Trace:
堆栈跟踪：
javax.faces.application.ViewExpiredException: /food.xhtmlNo saved view state could be found for the view identifier: /food.xhtml
at org.apache.myfaces.lifecycle.RestoreViewExecutor.execute(RestoreViewExecutor.java:128)
at org.apache.myfaces.lifecycle.LifecycleImpl.executePhase(LifecycleImpl.java:171)
at org.apache.myfaces.lifecycle.LifecycleImpl.execute(LifecycleImpl.java:118)
at javax.faces.webapp.FacesServlet.service(FacesServlet.java:189)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:304)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:240)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:164)
at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:462)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:164)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:100)
at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:563)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:118)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:399)
at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:317)
at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:204)
at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:182)
at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:311)
at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:886)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:908)
at java.lang.Thread.run(Thread.java:662)
And my web.xml:
还有我的 web.xml：
<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns="http://java.sun.com/xml/ns/javaee"
xmlns:web="http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd"
xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd"
id="WebApp_ID" version="3.0">
<display-name>PORTAL</display-name>
<session-config>
<session-timeout>180</session-timeout>
</session-config>
<welcome-file-list>
<welcome-file>index.html</welcome-file>
<welcome-file>index.xhtml</welcome-file>
<welcome-file>index.htm</welcome-file>
</welcome-file-list>
<servlet>
<servlet-name>Faces Servlet</servlet-name>
<servlet-class>javax.faces.webapp.FacesServlet</servlet-class>
<load-on-startup>1</load-on-startup>
</servlet>
<servlet-mapping>
<servlet-name>Faces Servlet</servlet-name>
<url-pattern>*.xhtml</url-pattern>
</servlet-mapping>
<servlet-mapping>
<servlet-name>Faces Servlet</servlet-name>
<url-pattern>*.jsf</url-pattern>
</servlet-mapping>
<servlet-mapping>
<servlet-name>Faces Servlet</servlet-name>
<url-pattern>*.faces</url-pattern>
</servlet-mapping>
<context-param>
<param-name>javax.faces.STATE_SAVING_METHOD</param-name>
<param-value>client</param-value>
</context-param>
<context-param>
<param-name>javax.servlet.jsp.jstl.fmt.localizationContext</param-name>
<param-value>resources.application</param-value>
</context-param>
<context-param>
<param-name>javax.faces.DEFAULT_SUFFIX</param-name>
<param-value>.xhtml</param-value>
</context-param>
</web-app>
Don't you ever met such error report?
你没有遇到过这样的错误报告吗？
采纳答案by gaffcz
SOLUTION:I had to consider which classes should be serializabled and which not.
解决方案：我必须考虑哪些类应该被序列化，哪些不能。
回答by mist
This might be a bit late to reply, but I had the same problem and I spent quite some time to solve it. So, I thought this might help someone else.
回复可能有点晚了，但我遇到了同样的问题，我花了很长时间来解决它。所以，我认为这可能会帮助别人。
By default, MyFacesdoes serialization of state, even when state is being saved on the server, while Mojarradoes not. So, if you have some beans that are not serializable, or which are using other beans that are not serializable, you will see that error (the server is not able to serialize the object).
默认情况MyFaces下，即使状态被保存在服务器上，也会对状态进行序列化，而Mojarra不会。因此，如果您有一些不可序列化的 bean，或者它们正在使用其他不可序列化的 bean，您将看到该错误（服务器无法序列化对象）。
You can disable the serialization so MyFaceswill work like Mojarra.
Check this link: ViewScoped Bean cause NotSerializableException
您可以禁用序列化，以便MyFaces像Mojarra. 检查此链接：ViewScoped Bean 导致 NotSerializableException
回答by lu4242
The problem you are experienced here is typical, and is caused because by default MyFaces generates a random secret for encode the view state. Each time the server restart, a new random secret is generated.
您在这里遇到的问题是典型的，这是因为默认情况下 MyFaces 会生成一个随机密钥来对视图状态进行编码。每次服务器重新启动时，都会生成一个新的随机密钥。
To solve this, you need to setup some web config params, specially org.apache.myfaces.SECRET and org.apache.myfaces.MAC_SECRET, so the same secret is used each time your server is restarted. Mojarra has something similar too, but I don't remember the param name at this moment.
为了解决这个问题，你需要设置一些 web 配置参数，特别是 org.apache.myfaces.SECRET 和 org.apache.myfaces.MAC_SECRET，所以每次你的服务器重新启动时都会使用相同的秘密。Mojarra 也有类似的东西，但我现在不记得参数名称。
Check this page Secure Your Application with MyFaces. There you can find all details you need to setup your encryption.
检查此页面使用 MyFaces 保护您的应用程序。在那里您可以找到设置加密所需的所有详细信息。
You can send questions about MyFaces by subscribing to Users and Dev Mailing Lists
您可以通过订阅用户和开发邮件列表来发送有关 MyFaces 的问题
回答by Leonel Martins
As said, on the other answer, one need to define the SECRET. I followed the instructions at Secure_Your_Application. I added the below lines to web.xml(change the secrets accordingly). And dont forget to the to download the unlimited strength JCE policy files.
如上所述，在另一个答案中，需要定义 SECRET。我按照Secure_Your_Application 上的说明进行操作。我添加了以下几行web.xml（相应地更改秘密）。并且不要忘记下载无限强度的 JCE 策略文件。
<context-param>
<param-name>org.apache.myfaces.ALGORITHM</param-name>
<param-value>AES</param-value>
</context-param>
<!-- Defines the secret (Base64 encoded) used to initialize the secret key
for encryption algorithm. The size of it depends on the algorithm used for encryption -->
<context-param>
<param-name>org.apache.myfaces.SECRET</param-name>
<param-value>MDEyMzQ1Njc4OTAxMjM0NTY3ODkwMTIz</param-value>
</context-param>
<!-- Define the initialization code (Bas64 encoded) that are used to initialize the secret key used
on the Message Authentication Code algorithm. The size of it depends on the algorithm used for mac calculation -->
<context-param>
<param-name>org.apache.myfaces.MAC_SECRET</param-name>
<param-value>YWJjZDEyMzQ=</param-value>
</context-param>
回答by Jayesh Deshmukh
I usually get this error. I am using myfaces 1.2 and websphere 7, but then I did not restart the server. I first stopped the server, then started again rather than doing a restart. That worked.
我通常会收到此错误。我使用的是 myfaces 1.2 和 websphere 7，但后来我没有重新启动服务器。我首先停止了服务器，然后再次启动而不是重新启动。那行得通。
