Eclipse (バージョン 3.5.2) にインストールしたばかりDrools plug-in
で、プラグインに付属の「Hello World」サンプルを実行しようとしています。
コードを実行するruntime error
と、次のスタック トレースが表示されます。
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:274)
at org.drools.compiler.PackageBuilderConfiguration.buildDialectConfigurationMap(PackageBuilderConfiguration.java:259)
at org.drools.compiler.PackageBuilderConfiguration.init(PackageBuilderConfiguration.java:176)
at org.drools.compiler.PackageBuilderConfiguration.<init>(PackageBuilderConfiguration.java:153)
at org.drools.compiler.PackageBuilder.<init>(PackageBuilder.java:242)
at org.drools.compiler.PackageBuilder.<init>(PackageBuilder.java:142)
at org.drools.builder.impl.KnowledgeBuilderProviderImpl.newKnowledgeBuilder(KnowledgeBuilderProviderImpl.java:29)
at org.drools.builder.KnowledgeBuilderFactory.newKnowledgeBuilder(KnowledgeBuilderFactory.java:29)
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:94)
at org.drools.rule.builder.dialect.java.JavaDialectConfiguration.init(JavaDialectConfiguration.java:55)
at org.drools.compiler.PackageBuilderConfiguration.addDialect(PackageBuilderConfiguration.java:270)
... 9 more
関連する Java コードの一部を次に示します。
public static final void main(String[] args) {
try {
// load up the knowledge base
KnowledgeBase kbase = readKnowledgeBase();
}
}
private static KnowledgeBase readKnowledgeBase() throws Exception {
KnowledgeBuilder kbuilder = KnowledgeBuilderFactory.newKnowledgeBuilder();
kbuilder.add(ResourceFactory.newClassPathResource("Sample.drl"), ResourceType.DRL);
KnowledgeBuilderErrors errors = kbuilder.getErrors();
if (errors.size() > 0) {
for (KnowledgeBuilderError error : errors) {
System.err.println(error);
}
throw new IllegalArgumentException("Could not parse knowledge.");
}
KnowledgeBase kbase = KnowledgeBaseFactory.newKnowledgeBase();
kbase.addKnowledgePackages(kbuilder.getKnowledgePackages());
return kbase;
}