私は、その機能の1つとして、ロボットがルールベースのシステムを使用できるようにするフレームワークを開発しています。私たちはRBSとしてJessから始め、今ではOpenJDK 6で実行されている開発マシンで動作するdrools（Drools 5.2.0 finalを使用）を実装したいと考えていました。
私たちのロボットコントローラーは、以前は1.4.3であったARM LinuxとJamVMを実行しますが、droolsに必要なクラスが欠落しているため、最近1.5.4をコンパイルしました。失敗した後、コントローラー用にコンパイルしたときと同じ構成を使用して仮想マシンにJamVMをインストールしましたが、同じ例外で失敗しました。
少し調べてみると、Drools + JamVMのバグレポートがありますが、これは一般的に機能することも意味します。
次のコードを使用してプリコンパイルされたルールでフレームワークを実行する場合...
kBase = KnowledgeBaseFactory.newKnowledgeBase();
ObjectInputStream in;
Collection<KnowledgePackage> kpkgs;
try {
in = new ObjectInputStream(Thread.currentThread().getContextClassLoader().getResourceAsStream(
packageFile));
kpkgs = (Collection<KnowledgePackage>) in.readObject();
in.close();
} catch(IOException e) {
throw new DisboticsException("Couldn't read drools knowledge package file!", e);
} catch(ClassNotFoundException e) {
throw new DisboticsException("Drools knowledge package file didn't contain expected instance.", e);
}
kBase.addKnowledgePackages(kpkgs);
kSession = kBase.newStatefulKnowledgeSession();
...この例外が発生しました：
java.lang.UnsupportedOperationException
at java.util.AbstractList.add(AbstractList.java:131)
at java.util.AbstractList.add(AbstractList.java:152)
at org.drools.rule.JavaDialectRuntimeData.write(JavaDialectRuntimeData.java:383)
at org.drools.rule.JavaDialectRuntimeData.merge(JavaDialectRuntimeData.java:266)
at org.drools.rule.JavaDialectRuntimeData.clone(JavaDialectRuntimeData.java:251)
at org.drools.rule.DialectRuntimeRegistry.merge(DialectRuntimeRegistry.java:110)
at org.drools.common.AbstractRuleBase.addPackages(AbstractRuleBase.java:496)
at org.drools.reteoo.ReteooRuleBase.addPackages(ReteooRuleBase.java:427)
at org.drools.impl.KnowledgeBaseImpl.addKnowledgePackages(KnowledgeBaseImpl.java:149)
at disbotics.core.config.DroolsRulesPlugin.initialize(DroolsRulesPlugin.java:76)
at disbotics.core.common.DisboticsCore.startFramework(DisboticsCore.java:109)
at disbotics.core.common.DisboticsCore.main(DisboticsCore.java:56)
Exception in thread "main" org.drools.RuntimeDroolsException: java.lang.UnsupportedOperationException
at org.drools.rule.JavaDialectRuntimeData.write(JavaDialectRuntimeData.java:386)
at org.drools.rule.JavaDialectRuntimeData.merge(JavaDialectRuntimeData.java:266)
at org.drools.rule.JavaDialectRuntimeData.clone(JavaDialectRuntimeData.java:251)
at org.drools.rule.DialectRuntimeRegistry.merge(DialectRuntimeRegistry.java:110)
at org.drools.common.AbstractRuleBase.addPackages(AbstractRuleBase.java:496)
at org.drools.reteoo.ReteooRuleBase.addPackages(ReteooRuleBase.java:427)
at org.drools.impl.KnowledgeBaseImpl.addKnowledgePackages(KnowledgeBaseImpl.java:149)
at disbotics.core.config.DroolsRulesPlugin.initialize(DroolsRulesPlugin.java:76)
at disbotics.core.common.DisboticsCore.startFramework(DisboticsCore.java:109)
at disbotics.core.common.DisboticsCore.main(DisboticsCore.java:56)
Caused by: java.lang.UnsupportedOperationException
at java.util.AbstractList.add(AbstractList.java:131)
at java.util.AbstractList.add(AbstractList.java:152)
at org.drools.rule.JavaDialectRuntimeData.write(JavaDialectRuntimeData.java:383)
...9 more
...これはOpenJDKで動作します。奇妙なことに、問題のリストJavaDialectRuntimeDataはを介して取得Collections.emptyList()され、二度と変更されることはありません（または、日食が示唆しています...）。
このコードを使用してベア.drlファイルで実行する場合：
Properties props = new Properties();
props.put("drools.dialect.java.compiler", "JANINO");
KnowledgeBuilderConfiguration kbConfig = KnowledgeBuilderFactory.newKnowledgeBuilderConfiguration(props,
(ClassLoader[]) null);
KnowledgeBuilder kBuilder = KnowledgeBuilderFactory.newKnowledgeBuilder(kbConfig);
kBuilder.add(ResourceFactory.newClassPathResource("disbotics/core/rules/drools/function.drl",
DroolsRulesPlugin.class), ResourceType.DRL);
kBuilder.add(ResourceFactory.newClassPathResource(rulesFile, DroolsRulesPlugin.class), ResourceType.DRL);
if(kBuilder.hasErrors()) {
String errorMessage = "";
for(KnowledgeBuilderError error:kBuilder.getErrors())
errorMessage = errorMessage + error.getMessage() + "\n";
throw new DisboticsException(errorMessage);
}
kBase = KnowledgeBaseFactory.newKnowledgeBase();
kBase.addKnowledgePackages(kBuilder.getKnowledgePackages());
kSession = kBase.newStatefulKnowledgeSession();
...ルールコンパイラから次の（予期しない）例外が発生します。
Exception in thread "main" disbotics.core.common.DisboticsException: Line 2:8 unexpected exception at input '"mvel"'. Exception: java.lang.UnsupportedOperationException. Stack trace:
java.lang.UnsupportedOperationException
at java.util.AbstractList.add(AbstractList.java:131)
at java.util.AbstractList.add(AbstractList.java:152)
at org.drools.lang.descr.PackageDescr.addAttribute(PackageDescr.java:138)
at org.drools.lang.api.impl.PackageDescrBuilderImpl.attribute(PackageDescrBuilderImpl.java:93)
at org.drools.lang.ParserHelper.start(ParserHelper.java:684)
at org.drools.lang.DRLParser.stringAttribute(DRLParser.java:1289)
at org.drools.lang.DRLParser.attribute(DRLParser.java:1062)
at org.drools.lang.DRLParser.statement(DRLParser.java:276)
at org.drools.lang.DRLParser.compilationUnit(DRLParser.java:155)
at org.drools.compiler.DrlParser.compile(DrlParser.java:225)
at org.drools.compiler.DrlParser.parse(DrlParser.java:136)
at org.drools.compiler.DrlParser.parse(DrlParser.java:141)
at org.drools.compiler.PackageBuilder.addPackageFromDrl(PackageBuilder.java:352)
at org.drools.compiler.PackageBuilder.addKnowledgeResource(PackageBuilder.java:538)
at org.drools.builder.impl.KnowledgeBuilderImpl.add(KnowledgeBuilderImpl.java:28)
at disbotics.core.config.DroolsRulesPlugin.initialize(DroolsRulesPlugin.java:55)
at disbotics.core.common.DisboticsCore.startFramework(DisboticsCore.java:109)
at disbotics.core.common.DisboticsCore.main(DisboticsCore.java:56)
[ERR 107] Line 2:8 mismatched input '"mvel"' expecting one of the following tokens: '[package, import, global, declare, function, rule, query]'.
Line 4:0 unexpected exception at input 'global'. Exception: java.util.EmptyStackException. Stack trace:
java.util.EmptyStackException
at java.util.Stack.pop(Stack.java:109)
at org.drools.lang.ParserHelper.popParaphrases(ParserHelper.java:421)
at org.drools.lang.ParserHelper.end(ParserHelper.java:732)
at org.drools.lang.DRLParser.globalStatement(DRLParser.java:401)
at org.drools.lang.DRLParser.statement(DRLParser.java:261)
at org.drools.lang.DRLParser.compilationUnit(DRLParser.java:155)
at org.drools.compiler.DrlParser.compile(DrlParser.java:225)
at org.drools.compiler.DrlParser.parse(DrlParser.java:136)
at org.drools.compiler.DrlParser.parse(DrlParser.java:141)
at org.drools.compiler.PackageBuilder.addPackageFromDrl(PackageBuilder.java:352)
at org.drools.compiler.PackageBuilder.addKnowledgeResource(PackageBuilder.java:538)
at org.drools.builder.impl.KnowledgeBuilderImpl.add(KnowledgeBuilderImpl.java:28)
at disbotics.core.config.DroolsRulesPlugin.initialize(DroolsRulesPlugin.java:55)
at disbotics.core.common.DisboticsCore.startFramework(DisboticsCore.java:109)
at disbotics.core.common.DisboticsCore.main(DisboticsCore.java:56)
Parser returned a null Package
Line 2:8 unexpected exception at input '"java"'. Exception: java.lang.UnsupportedOperationException. Stack trace:
java.lang.UnsupportedOperationException
at java.util.AbstractList.add(AbstractList.java:131)
at java.util.AbstractList.add(AbstractList.java:152)
at org.drools.lang.descr.PackageDescr.addAttribute(PackageDescr.java:138)
at org.drools.lang.api.impl.PackageDescrBuilderImpl.attribute(PackageDescrBuilderImpl.java:93)
at org.drools.lang.ParserHelper.start(ParserHelper.java:684)
at org.drools.lang.DRLParser.stringAttribute(DRLParser.java:1289)
at org.drools.lang.DRLParser.attribute(DRLParser.java:1062)
at org.drools.lang.DRLParser.statement(DRLParser.java:276)
at org.drools.lang.DRLParser.compilationUnit(DRLParser.java:155)
at org.drools.compiler.DrlParser.compile(DrlParser.java:225)
at org.drools.compiler.DrlParser.parse(DrlParser.java:136)
at org.drools.compiler.DrlParser.parse(DrlParser.java:141)
at org.drools.compiler.PackageBuilder.addPackageFromDrl(PackageBuilder.java:352)
at org.drools.compiler.PackageBuilder.addKnowledgeResource(PackageBuilder.java:538)
at org.drools.builder.impl.KnowledgeBuilderImpl.add(KnowledgeBuilderImpl.java:28)
at disbotics.core.config.DroolsRulesPlugin.initialize(DroolsRulesPlugin.java:57)
at disbotics.core.common.DisboticsCore.startFramework(DisboticsCore.java:109)
at disbotics.core.common.DisboticsCore.main(DisboticsCore.java:56)
[ERR 107] Line 2:8 mismatched input '"java"' expecting one of the following tokens: '[package, import, global, declare, function, rule, query]'.
Line 4:0 unexpected exception at input 'import'. Exception: java.util.EmptyStackException. Stack trace:
java.util.EmptyStackException
at java.util.Stack.pop(Stack.java:109)
at org.drools.lang.ParserHelper.popParaphrases(ParserHelper.java:421)
at org.drools.lang.ParserHelper.end(ParserHelper.java:732)
at org.drools.lang.DRLParser.importStatement(DRLParser.java:349)
at org.drools.lang.DRLParser.statement(DRLParser.java:258)
at org.drools.lang.DRLParser.compilationUnit(DRLParser.java:155)
at org.drools.compiler.DrlParser.compile(DrlParser.java:225)
at org.drools.compiler.DrlParser.parse(DrlParser.java:136)
at org.drools.compiler.DrlParser.parse(DrlParser.java:141)
at org.drools.compiler.PackageBuilder.addPackageFromDrl(PackageBuilder.java:352)
at org.drools.compiler.PackageBuilder.addKnowledgeResource(PackageBuilder.java:538)
at org.drools.builder.impl.KnowledgeBuilderImpl.add(KnowledgeBuilderImpl.java:28)
at disbotics.core.config.DroolsRulesPlugin.initialize(DroolsRulesPlugin.java:57)
at disbotics.core.common.DisboticsCore.startFramework(DisboticsCore.java:109)
at disbotics.core.common.DisboticsCore.main(DisboticsCore.java:56)
Line 6:0 unexpected exception at input 'rule'. Exception: java.util.EmptyStackException. Stack trace:
java.util.EmptyStackException
at java.util.Stack.pop(Stack.java:109)
at org.drools.lang.ParserHelper.popParaphrases(ParserHelper.java:421)
at org.drools.lang.ParserHelper.end(ParserHelper.java:732)
at org.drools.lang.DRLParser.rule(DRLParser.java:886)
at org.drools.lang.DRLParser.statement(DRLParser.java:267)
at org.drools.lang.DRLParser.compilationUnit(DRLParser.java:155)
at org.drools.compiler.DrlParser.compile(DrlParser.java:225)
at org.drools.compiler.DrlParser.parse(DrlParser.java:136)
at org.drools.compiler.DrlParser.parse(DrlParser.java:141)
at org.drools.compiler.PackageBuilder.addPackageFromDrl(PackageBuilder.java:352)
at org.drools.compiler.PackageBuilder.addKnowledgeResource(PackageBuilder.java:538)
at org.drools.builder.impl.KnowledgeBuilderImpl.add(KnowledgeBuilderImpl.java:28)
at disbotics.core.config.DroolsRulesPlugin.initialize(DroolsRulesPlugin.java:57)
at disbotics.core.common.DisboticsCore.startFramework(DisboticsCore.java:109)
at disbotics.core.common.DisboticsCore.main(DisboticsCore.java:56)
Parser returned a null Package
at disbotics.core.config.DroolsRulesPlugin.initialize(DroolsRulesPlugin.java:63)
at disbotics.core.common.DisboticsCore.startFramework(DisboticsCore.java:109)
at disbotics.core.common.DisboticsCore.main(DisboticsCore.java:56)
繰り返しになりますが、ルールのコンパイルはOpenJDKで問題なく機能しました。Janinoを使用しており、クラスパスで適切に参照されています（実行時に使用されるクラスパスは、Mavenビルドによって作成されるため、drools / janino /その他によって参照されるすべてのjarが含まれます）
ここで何が起こっているのか、DroolsをJamVMで動作させる方法を知っている人はいますか？