耶拿+颗粒+小程序中的滑

Question

我正在尝试将Jena库，Pellet和一些RPG 2d库Slick集成到一个applet中。 因此，基本上，当我在浏览器中运行小程序时，我收到此文件许可权错误（我正在使用的jar均已签名）：

   Exception in thread "Thread-15" java.lang.ExceptionInInitializerError
    at org.mindswap.pellet.ABox.<init>(ABox.java:208)
    at org.mindswap.pellet.KnowledgeBase.clear(KnowledgeBase.java:540)
    at org.mindswap.pellet.KnowledgeBase.<init>(KnowledgeBase.java:418)
    at org.mindswap.pellet.jena.PelletInfGraph.<init>(PelletInfGraph.java:99)
    at org.mindswap.pellet.jena.PelletReasoner.bind(PelletReasoner.java:95)
    at org.mindswap.pellet.jena.PelletReasoner.bind(PelletReasoner.java:53)
    at com.hp.hpl.jena.ontology.impl.OntModelImpl.generateGraph(OntModelImpl.java:2744)
    at com.hp.hpl.jena.ontology.impl.OntModelImpl.<init>(OntModelImpl.java:139)
    at com.hp.hpl.jena.ontology.impl.OntModelImpl.<init>(OntModelImpl.java:128)
    at com.hp.hpl.jena.rdf.model.ModelFactory.createOntologyModel(ModelFactory.java:410)
    at RPGGame.GameSelectionScreen.init(GameSelectionScreen.java:170)
    at RPGGame.RPGGame.initStatesList(RPGGame.java:39)
    at org.newdawn.slick.state.StateBasedGame.init(StateBasedGame.java:164)
    at org.newdawn.slick.AppletGameContainer$Container.initApplet(AppletGameContainer.java:272)
    at org.newdawn.slick.AppletGameContainer$ContainerPanel.initGL(AppletGameContainer.java:229)
    at org.newdawn.slick.AppletGameContainer$ContainerPanel.start(AppletGameContainer.java:216)
    at org.newdawn.slick.AppletGameContainer$1.run(AppletGameContainer.java:92)
    Caused by: java.security.AccessControlException: access denied      ("java.util.PropertyPermission"     "pellet.configuration" "read")
    at java.security.AccessControlContext.checkPermission(Unknown Source)
    at java.security.AccessController.checkPermission(Unknown Source)
    at java.lang.SecurityManager.checkPermission(Unknown Source)
    at java.lang.SecurityManager.checkPropertyAccess(Unknown Source)
    at java.lang.System.getProperty(Unknown Source)
    at org.mindswap.pellet.PelletOptions.<clinit>(PelletOptions.java:805)

在此先感谢，Ioana

Answer 1

该错误是因为ABox试图从PelletOptions中读取信息，这需要加载Pellet配置。 它通常会尝试从jar中读取此内容，但首先，它将仔细检查用户在系统属性中指定的位置是否不同于默认位置。 正是这种检查导致了错误。

您可以修改PelletOptions使其始终在jar中进行检查，而不必进行系统属性检查，或者您可以通过旋转applet安全性使它正常（我不知道这样做是否可行，以前从未使用过Applet）。