Question

我尝试使用以下代码动态加载jar资源。

    DownloadService ds; 

    try { 
        ds = (DownloadService)ServiceManager.lookup("javax.jnlp.DownloadService"); 

        // determine if a particular resource is cached
        URL url = 
                new URL("http://localhost:11090/MultiToolkitDemo/download/ubikey-1.0.2.5.jar"); 
        boolean cached = ds.isResourceCached(url, "1.0"); 
        // remove the resource from the cache 
        if (cached) { 
            ds.removeResource(url, "1.0"); 
        } 
        // reload the resource into the cache 
        DownloadServiceListener dsl = ds.getDefaultProgressWindow(); 
        ds.loadResource(url, "1.0", dsl); 
    } catch (Exception e) { 
        e.printStackTrace(); 
    }

但我得到的错误如下。

    cache: Create from verifier: JarSigningData{hasOnlySignedEntries=true, hasSingleCodeSource=true, hasMissingSignedEntries=false}
    network: Cache: Enable a new CacheEntry: http://localhost:11090/MultiToolkitDemo/download/ubikey-1.0.2.5.jar
    network: CleanupThread used 1 us
    network: Downloaded http://localhost:11090/MultiToolkitDemo/download/ubikey-1.0.2.5.jar: C:\Users\Administrator\AppData\LocalLow\Sun\Java\Deployment\cache\6.0\63\774e407f-457c5f64-1.0-
    cache: Adding MemoryCache entry: http://localhost:11090/MultiToolkitDemo/download/ubikey-1.0.2.5.jar
    network: Download Progress: jarsDone: 1
     2013-08-30 14:19:53,959     4881 [AWT-EventQueue-2] INFO  com.ktnet.pki.multibrowser.dialog.SelectCertificateDlg$10  -  MOBILE_PHONE  param BOKJIRO;KTNET;null;null;null
    security: blacklist: hasBeenModifiedSince 1377837583053 (we have 1377739208656)
    network: cache found [URL: http://localhost:11090/MultiToolkitDemo/download/ubikey-1.0.2.5.jar, 버전: null] prevalidated=false/0
    cache: MemoryCache replacing http://localhost:11090/MultiToolkitDemo/download/ubikey-1.0.2.5.jar (refcnt=2). Was: URL: http://localhost:11090/MultiToolkitDemo/download/ubikey-1.0.2.5.jar | C:\Users\Administrator\AppData\LocalLow\Sun\Java\Deployment\cache\6.0\63\774e407f-457c5f64-1.0-.idx Now: URL: http://localhost:11090/MultiToolkitDemo/download/ubikey-1.0.2.5.jar | C:\Users\Administrator\AppData\LocalLow\Sun\Java\Deployment\cache\6.0\63\774e407f-13638c52.idx
    cache: Reading Signers from 4389 http://localhost:11090/MultiToolkitDemo/download/ubikey-1.0.2.5.jar | C:\Users\Administrator\AppData\LocalLow\Sun\Java\Deployment\cache\6.0\63\774e407f-13638c52.idx
    cache: Done readSigners(http://localhost:11090/MultiToolkitDemo/download/ubikey-1.0.2.5.jar)
    cache:  Read manifest for http://localhost:11090/MultiToolkitDemo/download/ubikey-1.0.2.5.jar: read=72 full=5090
    Exception in thread "AWT-EventQueue-2" java.lang.NullPointerException
        at sun.plugin2.applet.JNLP2ClassLoader.getAppInfo(Unknown Source)
        at sun.plugin2.applet.Plugin2ClassLoader.isTrustedByTrustDecider(Unknown Source)
        at sun.plugin2.applet.Plugin2ClassLoader.getTrustedCodeSources(Unknown Source)
        at com.sun.deploy.security.CPCallbackHandler$ParentCallback.strategy(Unknown Source)
        at com.sun.deploy.security.CPCallbackHandler$ParentCallback.openClassPathElement(Unknown Source)
        at com.sun.deploy.security.DeployURLClassPath$JarLoader.getJarFile(Unknown Source)
        at com.sun.deploy.security.DeployURLClassPath$JarLoader.access$1000(Unknown Source)
        at com.sun.deploy.security.DeployURLClassPath$JarLoader$1.run(Unknown Source)
        at java.security.AccessController.doPrivileged(Native Method)
        at com.sun.deploy.security.DeployURLClassPath$JarLoader.ensureOpen(Unknown Source)
        at com.sun.deploy.security.DeployURLClassPath$JarLoader.<init>(Unknown Source)
        at com.sun.deploy.security.DeployURLClassPath$3.run(Unknown Source)
        at java.security.AccessController.doPrivileged(Native Method)
        at com.sun.deploy.security.DeployURLClassPath.getLoader(Unknown Source)
        at com.sun.deploy.security.DeployURLClassPath.getLoader(Unknown Source)
        at com.sun.deploy.security.DeployURLClassPath.getResource(Unknown Source)
        at sun.plugin2.applet.Plugin2ClassLoader$2.run(Unknown Source)
        at java.security.AccessController.doPrivileged(Native Method)
        at sun.plugin2.applet.Plugin2ClassLoader.findClassHelper(Unknown Source)
        at sun.plugin2.applet.JNLP2ClassLoader.findClass(Unknown Source)
        at sun.plugin2.applet.Plugin2ClassLoader.loadClass0(Unknown Source)
        at sun.plugin2.applet.Plugin2ClassLoader.loadClass(Unknown Source)
        at sun.plugin2.applet.Plugin2ClassLoader.loadClass(Unknown Source)
        at java.lang.ClassLoader.loadClass(Unknown Source)
        at com.ktnet.pki.multibrowser.certificate.infovine.InfovineController.init(InfovineController.java:19)

我认为AppInfo丢失了。有没有办法动态插入AppInfo。

顺便说一下在jnlp中指定jar就好了。

    <resources>
        <j2se version="1.6+" java-vm-args="-Dfile.encoding=UTF-8" />

        <jar href="ubikey-1.0.2.5.jar" />

    </resources>

Answer 1

它可能是java7中的一个错误。不知道那是肯定的。

这里的问题是除非我们每次手动清除缓存，否则应用程序不会启动   单击网页中的JNLP链接之前的时间。

可能的解决方案

尝试使用Java 6或Java 7 u12。

看where我发现了这个问题。

使用DownloadService可以使用WebStart动态加载jar吗？

1 个答案: