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I'm working on a project where I'd like to use Apache Tika and Apache Jena. However, when I try to run the project I get the following exception:

java.lang.NoSuchMethodError: org.slf4j.spi.LocationAwareLogger.log Lorg/slf4j/Marker;Ljava/lang/String;ILjava/lang/String; Ljava/lang/Object;Ljava/lang/Throwable;)V

My understanding is that this is because Apache Tika includes an old version of SLF4J (pre 1.6.0) and Apache Jena includes a newer version (1.6.0 or later), and that there is a breaking change between the two versions of SLF4J.

How do I get around this issue so that I can use both Tika and Jena at the same time?

Some existing posts talk about using Maven to work around this, but a) I don't use Maven and I'm not familiar enough with it to fully understand the solutions and b) I'm working on a development network that isn't connected to the internet.

Joshua Taylor
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James Baker
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    The second point is irrelevant - you can have a local maven repo proxy. Anyway, you control what ends up in your classpath? Put the newest version of slf4j into the classpath and you should be fine. Older versions of slf4j lack features but newer version are backwards compatible. – Boris the Spider Jul 01 '13 at 14:02

3 Answers3

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slf4j is actually fairly compatible across versions for many usages. Jena does not use many features of SLF4j. It does not LocationAwareLogger as far as I'm aware. It may work with pre 1.6.X. While nothing is guaranteed (AKA you have to test it), it's worth a try.

If that fails, you'll need to rebuild one system and tweak what needs to be changed. Both systems are open source with both code and build system is available.

AndyS
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I wouldn't use these 2 libraries until they have the same version unless I'm absolutely have to do that.

If you think so, then a good explanation of the issue is here: java-classpath-classloading-multiple-versions-of-the-same-jar-project

Community
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Tala
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The solution was to change the order of the libraries so that the library with the newer version of SLF4J (Apache Jena) was before the older version(s) on the build path.

James Baker
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