QuestionsAndAnswers

Apache Jackrabbit Questions and Answers

This page is an alternative to the Jackrabbit mailing lists for people who prefer using a web forum instead of a mailing list for asking questions. Please feel free to add any Jackrabbit questions or answers here. The best questions will be incorporated into our website documentation as the Jackrabbit FAQ.

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Where the "ObjectPersistenceManager" save file?

Question: I use "org.apache.jackrabbit.core.state.obj.ObjectPersistenceManager" for the PersistenceManager.I create a node, then upload a file.after that i also success get the file.but i want know where "ObjectPersistenceManager" save the file.i can't find it in my file system.En,my system is windows.

Why no node SPI?

Question: I read in the FAQ that the interface was not intended to provide a SPI for attaching to other storage. Specifically, it says that you could probably achieve this for a read-only link to an existing relational database table, but it says you shouldn't/couldn't do it for read/write relational data.

I am curious why this closed architecture? I am considering this for a major project bt need the ability to map to relational schemas and other existing content stores, including other document management systems, and could even envision using that mechanism to federate multiple Jackrabit repositories into a central repository. I thought I might just need to extend VersionImpl or one of the other Node types and override some of the methods.

I would even envision implementing node types that map to transient runtime data such as performance counters etc.

Can you elaborate as to what architectural/design issues make this not possible. Or, is it just a philosophical point of view or ? This is one of the powerful capabilities that Slide offers. I understand that putting this abstraction over the RDBMS would have performance issues, but assuming my use case isn't sensitive to that, what are the reasons it won't work?

Thank you very much.

Where can I find examples of using the JCR API?

Answer: Please check the following:

• The First Hops document

• The ExamplesPage

If you have ideas of good examples you'd like to see, please submit your ideas as Jackrabbit enhancements!

Is there a way to use Jackrabbit without access control, or to get it working without changing JVM properties?

I'm using/evaluating Apache Jackrabbit for an open source project (platypuswiki.sf.net). My application is distributable as a War file (java webapp standard format). My problem is related to the Jackrabbit authentication. I see, from your examples, the need of the jaas.config definition. I'd like that my users do not have to change its tomcat/jetty jvm configuration settings: -Djava.security.auth.login.config= blah blah/jaas.config.

Answer: The JAAS configuration is no longer required for simple deployments. Starting from Apache Jackrabbit version 1.0 you do not need to set the JAAS login configuration options unless you want to override the default settings. See JCR-351 for the background and resolution of this issue.

Question: Thank you for the response. I have understood, that I have to use "TransientRepository" in place of "Repository" for omit the JAAS configuration. Is it true ?

What are others differences (advantages/disavantages) of using "TransientRepository" in place of "Repository" implmentation ?

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Supported operations

Questions:

1. I have saw that NamespaceRegistry.unregisterNamespace(..) is not supported. Is this feature planned in next releases ? Or there are other ways to change a namespace URI of a registered namespace ?

Answer: See this mail: http://article.gmane.org/gmane.comp.apache.jackrabbit.devel/6836

2. Also, I have saw that the Xpath function "contains" is not supported: javax.jcr.query.InvalidQueryException: Unsupported function: contains. There is a way for searching (full-text keyword search) into a value of a named property over all the workspace ?

Solved We need to use jcr:contains() function

There is a way for accessing, bypassing JCR pure std api, at lucene Index ?

How do I use Jackrabbit in MY projects with Maven 2 ?

If you are using maven 2, happily the releases of Jackrabbit are kept in the central maven repo. Put the following into your projects pom.xml:

       <dependency>
           <groupId>org.apache.jackrabbit</groupId>
           <artifactId>jackrabbit-core</artifactId>
           <version>1.3.3</version>
       </dependency>

As Jackrabbit depends on JCR (of course) you will also need to add:

    <dependency>
      <groupId>javax.jcr</groupId>
      <artifactId>jcr</artifactId>
      <version>1.0</version>
    </dependency>

Syntax errors in CND files

If you get annoying errors like: "Missing ']' delimiter for end of node type name", the chances are you are using names that have underscores in them ! (cryptic, I know). Remove the underscores and you are good to go !

Poor Performance when Implementing Global Revisioning & Content Set

We are in the process of evaluating Jackrabbit as a content repository for our internal content storage system. The content stored are all XML documents that are stored as a property in the node. The repository stores versioned/non-versioned nodes and typically nodes under certain root nodes are all revisioned. We are implementing full versioning capabilities similar to Subversion so that every commit results in a changeset node being created which refers to all the changed documents during this operation also we have to create a global revision so that a user can retrieve the repository state at a particular point in time. So we have implemented a tree walking which walks the tree and put the global revision reference to all the nodes in the repository. So our repository looks like the following:

root

• - Root1 - Root2

changeset Root

• - cs1 - cs2

Global Revision Root

• - global revision 1 - global revision 2

Each cs1 is referencable and contains a property of type reference pointing to global revision. Each global revision is also. referencable. Each Root1 has two referencable properties pointing to cs-x and global revision x. The performance is really bad it takes 10 minutes for a repository with 100 documents.

Have anybody tried implementing the concept of global revision & Change Set in Content Repository??? Any Suggestions???

JAR Files that Work with JackRabbit V1.3.3

First Hops Hop 0: Getting started is outdated when using JackRabbit 1.3.3. In particular you need to use lucene-core-1.9-final.jar rather than lucene-1.4.3.jar. Also, the latest logging subsystems work fine: log4j-api-1.4.3.jar, slf4j-log4j12-1.4.3.jar, log4j-1.2.15.jar, slf4j-api-1.4.3,jar.

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Bugs & Known Limitations

IllegalStateException: unread block data

Question: sometimes is thrown an exception in obtaining the stream to the Object stored in Jackrabbit:

java.lang.IllegalStateException: unread block data

• at java.io.ObjectInputStream$BlockDataInputStream.setBlockDataMode(ObjectInputStream.java:2375) at java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1361) at java.io.ObjectInputStream.defaultReadFields(ObjectInputStream.java:1945) at java.io.ObjectInputStream.readSerialData(ObjectInputStream.java:1869) at java.io.ObjectInputStream.readOrdinaryObject(ObjectInputStream.java:1753) at java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1329) at java.io.ObjectInputStream.readObject(ObjectInputStream.java:351) at sun.rmi.server.UnicastRef.unmarshalValue(UnicastRef.java:306) at sun.rmi.server.UnicastRef.invoke(UnicastRef.java:155) at org.apache.jackrabbit.rmi.server.ServerProperty_Stub.getValue(Unknown Source) at org.apache.jackrabbit.rmi.client.ClientProperty.getValue(ClientProperty.java:137) at org.apache.jackrabbit.rmi.client.ClientProperty.getStream(ClientProperty.java:121)

This happens using version 1.3.3, in unpredictable manner. Is it a bug or a feature? Any suggestion would be useful.

Extractor dependency not found

Question: I'm a new Jackrabbit user. When I run the "FirstHop.java" from " http://jackrabbit.apache.org/first-hops.html", I get the following warnings (whole log posted; the person answering should feel free to edit down to the most important lines.)

 496 [main] INFO org.apache.jackrabbit.core.RepositoryImpl - Starting repository...
 578 [main] INFO org.apache.jackrabbit.core.fs.local.LocalFileSystem - LocalFileSystem initialized at path repository/repository
 1218 [main] INFO org.apache.jackrabbit.core.nodetype.NodeTypeRegistry - no custom node type definitions found
 1236 [main] INFO org.apache.jackrabbit.core.fs.local.LocalFileSystem - LocalFileSystem initialized at path repository/version
 2945 [main] INFO org.apache.jackrabbit.core.persistence.bundle.util.ConnectionRecoveryManager - Database: Apache Derby / 10.3.2.1 - (599110)
 2945 [main] INFO org.apache.jackrabbit.core.persistence.bundle.util.ConnectionRecoveryManager - Driver: Apache Derby Embedded JDBC Driver / 10.3.2.1 - (599110)
 4607 [main] INFO org.apache.jackrabbit.core.RepositoryImpl - initializing workspace 'default'...
 4609 [main] INFO org.apache.jackrabbit.core.fs.local.LocalFileSystem - LocalFileSystem initialized at path repository/workspaces/default
 4716 [main] INFO org.apache.jackrabbit.core.persistence.bundle.util.ConnectionRecoveryManager - Database: Apache Derby / 10.3.2.1 - (599110)
 4716 [main] INFO org.apache.jackrabbit.core.persistence.bundle.util.ConnectionRecoveryManager - Driver: Apache Derby Embedded JDBC Driver / 10.3.2.1 - (599110)
 5515 [main] INFO org.apache.jackrabbit.core.RepositoryImpl - workspace 'default' initialized
 5860 [main] WARN org.apache.jackrabbit.core.query.lucene.JackrabbitTextExtractor - Extractor dependency not found: org.apache.jackrabbit.extractor.MsWordTextExtractor
 java.lang.NoClassDefFoundError
        at org.apache.jackrabbit.extractor.MsWordTextExtractor.class$(MsWordTextExtractor.java:37)
        at org.apache.jackrabbit.extractor.MsWordTextExtractor.<clinit>(MsWordTextExtractor.java:43)
        at java.lang.Class.forName0(Native Method)
        at java.lang.Class.forName(Class.java:164)
        at org.apache.jackrabbit.core.query.lucene.JackrabbitTextExtractor.<init>(JackrabbitTextExtractor.java:113)
        at org.apache.jackrabbit.core.query.lucene.SearchIndex.createTextExtractor(SearchIndex.java:881)
        at org.apache.jackrabbit.core.query.lucene.SearchIndex.doInit(SearchIndex.java:395)
        at org.apache.jackrabbit.core.query.AbstractQueryHandler.init(AbstractQueryHandler.java:48)
        at org.apache.jackrabbit.core.SearchManager.initializeQueryHandler(SearchManager.java:573)
        at org.apache.jackrabbit.core.SearchManager.<init>(SearchManager.java:255)
        at org.apache.jackrabbit.core.RepositoryImpl.getSystemSearchManager(RepositoryImpl.java:625)
        at org.apache.jackrabbit.core.RepositoryImpl.access$300(RepositoryImpl.java:104)
        at org.apache.jackrabbit.core.RepositoryImpl$WorkspaceInfo.getSearchManager(RepositoryImpl.java:1613)
        at org.apache.jackrabbit.core.RepositoryImpl.initWorkspace(RepositoryImpl.java:606)
        at org.apache.jackrabbit.core.RepositoryImpl.initStartupWorkspaces(RepositoryImpl.java:415)
        at org.apache.jackrabbit.core.RepositoryImpl.<init>(RepositoryImpl.java:305)
        at org.apache.jackrabbit.core.RepositoryImpl.create(RepositoryImpl.java:557)
        at org.apache.jackrabbit.core.TransientRepository$2.getRepository(TransientRepository.java:245)
        at org.apache.jackrabbit.core.TransientRepository.startRepository(TransientRepository.java:265)
        at org.apache.jackrabbit.core.TransientRepository.login(TransientRepository.java:333)
        at org.apache.jackrabbit.core.TransientRepository.login(TransientRepository.java:388)
        at org.lockss.jackrabbit.FirstHop.main(FirstHop.java:26)
 Caused by: java.lang.ClassNotFoundException: org.textmining.text.extraction.WordExtractor
        at java.net.URLClassLoader$1.run(URLClassLoader.java:200)
        at java.security.AccessController.doPrivileged(Native Method)
        at java.net.URLClassLoader.findClass(URLClassLoader.java:188)
        at java.lang.ClassLoader.loadClass(ClassLoader.java:306)
        at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:268)
        at java.lang.ClassLoader.loadClass(ClassLoader.java:251)
        at java.lang.ClassLoader.loadClassInternal(ClassLoader.java:319)
        at java.lang.Class.forName0(Native Method)
        at java.lang.Class.forName(Class.java:164)
        ... 22 more
 5913 [main] WARN org.apache.jackrabbit.core.query.lucene.JackrabbitTextExtractor - Extractor dependency not found: org.apache.jackrabbit.extractor.PdfTextExtractor
 java.lang.NoClassDefFoundError: org/pdfbox/pdmodel/PDDocument
        at java.lang.Class.forName0(Native Method)
        at java.lang.Class.forName(Class.java:164)
        at org.apache.jackrabbit.core.query.lucene.JackrabbitTextExtractor.<init>(JackrabbitTextExtractor.java:113)
        at org.apache.jackrabbit.core.query.lucene.SearchIndex.createTextExtractor(SearchIndex.java:881)
        at org.apache.jackrabbit.core.query.lucene.SearchIndex.doInit(SearchIndex.java:395)
        at org.apache.jackrabbit.core.query.AbstractQueryHandler.init(AbstractQueryHandler.java:48)
        at org.apache.jackrabbit.core.SearchManager.initializeQueryHandler(SearchManager.java:573)
        at org.apache.jackrabbit.core.SearchManager.<init>(SearchManager.java:255)
        at org.apache.jackrabbit.core.RepositoryImpl.getSystemSearchManager(RepositoryImpl.java:625)
        at org.apache.jackrabbit.core.RepositoryImpl.access$300(RepositoryImpl.java:104)
        at org.apache.jackrabbit.core.RepositoryImpl$WorkspaceInfo.getSearchManager(RepositoryImpl.java:1613)
        at org.apache.jackrabbit.core.RepositoryImpl.initWorkspace(RepositoryImpl.java:606)
        at org.apache.jackrabbit.core.RepositoryImpl.initStartupWorkspaces(RepositoryImpl.java:415)
        at org.apache.jackrabbit.core.RepositoryImpl.<init>(RepositoryImpl.java:305)
        at org.apache.jackrabbit.core.RepositoryImpl.create(RepositoryImpl.java:557)
        at org.apache.jackrabbit.core.TransientRepository$2.getRepository(TransientRepository.java:245)
        at org.apache.jackrabbit.core.TransientRepository.startRepository(TransientRepository.java:265)
        at org.apache.jackrabbit.core.TransientRepository.login(TransientRepository.java:333)
        at org.apache.jackrabbit.core.TransientRepository.login(TransientRepository.java:388)
        at org.lockss.jackrabbit.FirstHop.main(FirstHop.java:26)
 6063 [main] INFO org.apache.jackrabbit.core.fs.local.LocalFileSystem - LocalFileSystem initialized at path repository/repository/index
 6422 [main] INFO org.apache.jackrabbit.core.query.lucene.SearchIndex - Index initialized: repository/repository/index Version: 2
 6429 [main] WARN org.apache.jackrabbit.core.query.lucene.JackrabbitTextExtractor - Extractor dependency not found: org.apache.jackrabbit.extractor.MsWordTextExtractor
 java.lang.NoClassDefFoundError
        at java.lang.Class.forName0(Native Method)
        at java.lang.Class.forName(Class.java:164)
        at org.apache.jackrabbit.core.query.lucene.JackrabbitTextExtractor.<init>(JackrabbitTextExtractor.java:113)
        at org.apache.jackrabbit.core.query.lucene.SearchIndex.createTextExtractor(SearchIndex.java:881)
        at org.apache.jackrabbit.core.query.lucene.SearchIndex.doInit(SearchIndex.java:395)
        at org.apache.jackrabbit.core.query.AbstractQueryHandler.init(AbstractQueryHandler.java:48)
        at org.apache.jackrabbit.core.SearchManager.initializeQueryHandler(SearchManager.java:573)
        at org.apache.jackrabbit.core.SearchManager.<init>(SearchManager.java:255)
        at org.apache.jackrabbit.core.RepositoryImpl$WorkspaceInfo.getSearchManager(RepositoryImpl.java:1613)
        at org.apache.jackrabbit.core.RepositoryImpl.initWorkspace(RepositoryImpl.java:606)
        at org.apache.jackrabbit.core.RepositoryImpl.initStartupWorkspaces(RepositoryImpl.java:415)
        at org.apache.jackrabbit.core.RepositoryImpl.<init>(RepositoryImpl.java:305)
        at org.apache.jackrabbit.core.RepositoryImpl.create(RepositoryImpl.java:557)
        at org.apache.jackrabbit.core.TransientRepository$2.getRepository(TransientRepository.java:245)
        at org.apache.jackrabbit.core.TransientRepository.startRepository(TransientRepository.java:265)
        at org.apache.jackrabbit.core.TransientRepository.login(TransientRepository.java:333)
        at org.apache.jackrabbit.core.TransientRepository.login(TransientRepository.java:388)
        at org.lockss.jackrabbit.FirstHop.main(FirstHop.java:26)
 6438 [main] WARN org.apache.jackrabbit.core.query.lucene.JackrabbitTextExtractor - Extractor dependency not found: org.apache.jackrabbit.extractor.PdfTextExtractor
 java.lang.NoClassDefFoundError: org/pdfbox/pdmodel/PDDocument
        at java.lang.Class.forName0(Native Method)
        at java.lang.Class.forName(Class.java:164)
        at org.apache.jackrabbit.core.query.lucene.JackrabbitTextExtractor.<init>(JackrabbitTextExtractor.java:113)
        at org.apache.jackrabbit.core.query.lucene.SearchIndex.createTextExtractor(SearchIndex.java:881)
        at org.apache.jackrabbit.core.query.lucene.SearchIndex.doInit(SearchIndex.java:395)
        at org.apache.jackrabbit.core.query.AbstractQueryHandler.init(AbstractQueryHandler.java:48)
        at org.apache.jackrabbit.core.SearchManager.initializeQueryHandler(SearchManager.java:573)
        at org.apache.jackrabbit.core.SearchManager.<init>(SearchManager.java:255)
        at org.apache.jackrabbit.core.RepositoryImpl$WorkspaceInfo.getSearchManager(RepositoryImpl.java:1613)
        at org.apache.jackrabbit.core.RepositoryImpl.initWorkspace(RepositoryImpl.java:606)
        at org.apache.jackrabbit.core.RepositoryImpl.initStartupWorkspaces(RepositoryImpl.java:415)
        at org.apache.jackrabbit.core.RepositoryImpl.<init>(RepositoryImpl.java:305)
        at org.apache.jackrabbit.core.RepositoryImpl.create(RepositoryImpl.java:557)
        at org.apache.jackrabbit.core.TransientRepository$2.getRepository(TransientRepository.java:245)
        at org.apache.jackrabbit.core.TransientRepository.startRepository(TransientRepository.java:265)
        at org.apache.jackrabbit.core.TransientRepository.login(TransientRepository.java:333)
        at org.apache.jackrabbit.core.TransientRepository.login(TransientRepository.java:388)
        at org.lockss.jackrabbit.FirstHop.main(FirstHop.java:26)
 6448 [main] INFO org.apache.jackrabbit.core.fs.local.LocalFileSystem - LocalFileSystem initialized at path repository/workspaces/default/index
 6456 [main] INFO org.apache.jackrabbit.core.query.lucene.SearchIndex - Index initialized: repository/workspaces/default/index Version: 2
 6456 [main] INFO org.apache.jackrabbit.core.RepositoryImpl - Repository started
 6457 [main] INFO org.apache.jackrabbit.core.TransientRepository - Transient repository initialized
 6532 [main] INFO org.apache.jackrabbit.core.TransientRepository - Session opened
 Logged in as anonymous to a Jackrabbit repository.
 6550 [main] INFO org.apache.jackrabbit.core.TransientRepository - Session closed
 6550 [main] INFO org.apache.jackrabbit.core.RepositoryImpl - Shutting down repository...
 6553 [IndexMerger] INFO org.apache.jackrabbit.core.query.lucene.IndexMerger - IndexMerger terminated
 6558 [main] INFO org.apache.jackrabbit.core.query.lucene.SearchIndex - Index closed: repository/repository/index
 6558 [main] INFO org.apache.jackrabbit.core.RepositoryImpl - shutting down workspace 'default'...
 6559 [main] INFO org.apache.jackrabbit.core.observation.ObservationDispatcher - Notification of EventListeners stopped.
 6559 [IndexMerger] INFO org.apache.jackrabbit.core.query.lucene.IndexMerger - IndexMerger terminated
 6606 [main] INFO org.apache.jackrabbit.core.query.lucene.SearchIndex - Index closed: repository/workspaces/default/index
 6639 [main] INFO org.apache.jackrabbit.core.persistence.bundle.DerbyPersistenceManager - Database 'repository/workspaces/default/db' shutdown.
 6643 [main] ERROR org.apache.jackrabbit.core.persistence.bundle.util.ConnectionRecoveryManager - failed to close connection, reason: No current connection., state/code: 08003/40000
 6645 [main] INFO org.apache.jackrabbit.core.RepositoryImpl - workspace 'default' has been shutdown
 6661 [main] INFO org.apache.jackrabbit.core.persistence.bundle.DerbyPersistenceManager - Database 'repository/version/db' shutdown.
 6661 [main] ERROR org.apache.jackrabbit.core.persistence.bundle.util.ConnectionRecoveryManager - failed to close connection, reason: No current connection.,  state/code: 08003/40000
 6678 [main] INFO org.apache.jackrabbit.core.RepositoryImpl - Repository has been shutdown
 6678 [main] INFO org.apache.jackrabbit.core.TransientRepository - Transient repository shut down

I'm worried about the "Extractor Dependencies not found". What could be causing this?

Answer: You have to include in your project the following libraries:

• PDFBox-0.7.3.jar (See PDFBox project http://www.pdfbox.org/)

• poi-3.0.2-FINAL-20080204.jar (See POI project http://poi.apache.org/)

• tm-extractors-0.4.jar ( http://www.ibiblio.org/maven/org.textmining/jars/tm-extractors-0.4.jar])