When creating new Drools Runtime from Drools plugin bundled to JBT org.eclipse.jdt.core*.jar file is not included in this runtime and therefore when running DroolTest.java this error is displayed in console:
org.drools.RuntimeDroolsException: Unable to load dialect 'org.drools.rule.builder.dialect.java.JavaDialectConfiguration:java:org.drools.rule.builder.dialect.java.JavaDialectConfiguration'
at org.drools.compiler.PackageBuilderConfiguration.addDialect(PackageBuilderConfiguration.java:277)
at org.drools.compiler.PackageBuilderConfiguration.buildDialectConfigurationMap(PackageBuilderConfiguration.java:262)
at org.drools.compiler.PackageBuilderConfiguration.init(PackageBuilderConfiguration.java:175)
at org.drools.compiler.PackageBuilderConfiguration.<init>(PackageBuilderConfiguration.java:153)
at org.drools.compiler.PackageBuilder.<init>(PackageBuilder.java:218)
at org.drools.compiler.PackageBuilder.<init>(PackageBuilder.java:146)
at org.drools.builder.impl.KnowledgeBuilderFactoryServiceImpl.newKnowledgeBuilder(KnowledgeBuilderFactoryServiceImpl.java:34)
at org.drools.builder.KnowledgeBuilderFactory.newKnowledgeBuilder(KnowledgeBuilderFactory.java:46)
at com.sample.DroolsTest.readKnowledgeBase(DroolsTest.java:39)
at com.sample.DroolsTest.main(DroolsTest.java:23)
Caused by: java.lang.RuntimeException: The Eclipse JDT Core jar is not in the classpath
at org.drools.rule.builder.dialect.java.JavaDialectConfiguration.setCompiler(JavaDialectConfiguration.java:93)
at org.drools.rule.builder.dialect.java.JavaDialectConfiguration.init(JavaDialectConfiguration.java:54)
at org.drools.compiler.PackageBuilderConfiguration.addDialect(PackageBuilderConfiguration.java:273)
... 9 more