Cannot add libraries to xtext Project in Eclipse (returns error)

问题

Firstly, I created an xtext project using default values (with the simple Greetings grammar which comes as an example).

I created then a .java file with some code (that can be seen below) and added it to the validation folder.

I have loaded some jars to the build path as I would do in a normal Java Project. If I run my specific java file as a standalone it will load the libraries and run the code. The java file is quite simple:

import org.semanticweb.owlapi.apibinding.OWLManager;
import org.semanticweb.owlapi.model.OWLOntologyCreationException;
import org.semanticweb.owlapi.model.OWLOntologyManager;
import org.xtext.example.mydsl.myDsl.Greeting;

public static void main(String[] args){
    Greeting hey = null;
    try {
        test(hey);
    } catch (OWLOntologyCreationException e) {
        e.printStackTrace();
    }
}

public static void test(Greeting imp) throws OWLOntologyCreationException {
    OWLOntologyManager manager = OWLManager.createOWLOntologyManager();
    System.out.println("success!");     
}

However, if a call the "test" function from the .xtend validator file, it will generate this error:

java.lang.NoClassDefFoundError: org/semanticweb/owlapi/model/OWLOntologyCreationException
at org.xtext.example.mydsl.validation.MyDslValidator.checkGreetingStartsWithCapital(MyDslValidator.java:24)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
/* (has some more "at" in the middle) */
Caused by: java.lang.ClassNotFoundException: org.semanticweb.owlapi.model.OWLOntologyCreationException cannot be found by org.xtext.example.mydsl_1.0.0.qualifier
at org.eclipse.osgi.internal.loader.BundleLoader.findClassInternal(BundleLoader.java:461)
at org.eclipse.osgi.internal.loader.BundleLoader.findClass(BundleLoader.java:372)
at org.eclipse.osgi.internal.loader.BundleLoader.findClass(BundleLoader.java:364)
at org.eclipse.osgi.internal.loader.ModuleClassLoader.loadClass(ModuleClassLoader.java:161)
at java.lang.ClassLoader.loadClass(ClassLoader.java:357)
... 32 more

When it mentioned "cannot be found by org.xtext.example.mydsl_1.0.0.qualifier" I assumed the problem was in the manifest, but I've tried adding the libraries to the manifest in every way possible but to no avail.

回答1:

if you add libs to the buildpath

copy it to a new lib folder inside the plugin
adapt the manifest and add the jars as entries (runtime tab, classpath section)
add the jars to be included in build.properties (there should be a warning and a quickfix)

来源：https://stackoverflow.com/questions/40731406/cannot-add-libraries-to-xtext-project-in-eclipse-returns-error

标签

java

eclipse

libraries

dsl

xtext