Why/Where does Eclipse inject extra libraries such as JPA 1.0?

Question

I'm suddenly getting this error when attempting to run anything within the context of Eclipse:

Caused by: java.lang.NoSuchMethodError: javax.persistence.spi.PersistenceUnitInfo.getValidationMode()Ljavax/persistence/ValidationMode;

I know this is the old JPA 1.0 spec being used whereas my project uses JPA 2.0. I can run my unit/integration tests no problem via Maven and IDEA, but if I run them in Eclipse (tried Kepler and Luna) I get the error.

Doing a little digging I found the older library being injected via the ProjectClassLoader:

ProjectClassLoader: entry= $HOME/.m2/repository/javax/persistence/persistence-api/1.0.2/persistence-api-1.0.2.jar

However it does not show up in my Maven dependencies or transitive dependencies. This is not the first time I've seen this. The last time I deleted my project and recreated it, but that approach failed this time. I've also tried disabling the JPA Facet.

How can I solve this?

Answer 1

There are 2 places to look. Both are under project properties.

First if your project is using facets look at that section. Three will be a facet listed for JPA. It should be checked and the drop down to the right should be 2.0 (or 2.1).

Next there is also a JPA tab just up from there. That has several tabs under it but the main thing is to set your JPA version and specify the implementation. This is probably where you are pulling in the 1.0 jar.

If you have facets turned on make sure the two places are consistent. You can get them out of sync quite easily and it is confusing and annoying to figure out.

Answer 2

I was finally able to "solve" this -- at least get myself working again. Here's what I did:

1. deleted my project(s) within Eclipse
2. deleted both the .classpath and .project files on disk (eg find . -name ".classpath" | xargs rm)
3. reimported my Maven project

And magically the JPA 1.0 is not being included in the project anymore. @Terry had some good info, but my configuration appeared correct per his notes. I think this is just a work-around and that there's possibly a bug lurking within Eclipse Luna with regard to this.