title: FileNotFoundException during JNLP download
body: <p>I was looking for a solution of this problem for weeks now, but did not find anything, which really related to my problem / or I already tried all suggested solutions, without any success.</p>
  
  <p>I have a <code>JNLP</code> file, which is downloaded by the <code>javaws</code> properly (I think), but then before launching, it complains about not finding some files in the /tmp directory. Exact error message is:</p>
  
  <pre><code>CouldNotLoadArgumentException[ Could not load file/URL specified: /tmp/tmp_cache8259898691262575141.tmp]
  at com.sun.javaws.Main.launchApp(Unknown Source)
  at com.sun.javaws.Main.continueInSecureThread(Unknown Source)
  at com.sun.javaws.Main.access$000(Unknown Source)
  at com.sun.javaws.Main$1.run(Unknown Source)
  at java.lang.Thread.run(Thread.java:745)
  Caused by: java.io.FileNotFoundException: /tmp/tmp_cache8259898691262575141.tmp (Nincs ilyen fájl vagy könyvtár)
      at java.io.FileInputStream.open0(Native Method)
      at java.io.FileInputStream.open(FileInputStream.java:195)
      at java.io.FileInputStream.&lt;init&gt;(FileInputStream.java:138)
      at java.io.FileInputStream.&lt;init&gt;(FileInputStream.java:93)
      at com.sun.javaws.jnl.LaunchDescFactory.buildDescriptor(Unknown Source)
      ... 5 more
  </code></pre>
  
  <p>I checked the <code>/tmp</code>, the folder is of course there, and is writable. Funny thing is, that during downloading the <code>tmp_cacheNNNNNN.tmp</code> files are there! They appear one-by-one, as the download progress moves on. However when the download is finished something (<code>javaws</code>?) deletes all of them, and then starts to complain about missing them.</p>
  
  <p>I have JNLP caching turned on (and intend to have it cached locally). I tried with <code>JRE 1.8.0_40</code>, <code>1.8.0_65</code>, <code>1.8.0_66</code>, all gives the same result. Same result on windows and linux, both complain about missing files in the temp folder.
  The last JRE I managed to start is the <code>1.8.0_25</code>, and seems to work with <code>1.8.0_72</code> (beta). However the downloaded jar files are still not cached! (if I open up the jcontrol application and look into the cache, the JAR files are not there, and I also don't know why).</p>
  
  <p>My <code>JNLP</code> looks like this:</p>
  
  <pre class="lang-xml prettyprint-override"><code>&lt;?xml version="1.0" encoding="utf-8"?&gt;
  
  &lt;jnlp spec="7.0+"
        codebase="http://localhost:8080/jbaf-server/jnlp/swing-client"
        href="http://localhost:8080/jbaf-server/clientDownload/client.jnlp" &gt;
      &lt;information&gt;
          &lt;title&gt;Swing Client&lt;/title&gt;
          &lt;vendor&gt;www.xy.z&lt;/vendor&gt;
          &lt;description&gt;Swing Client&lt;/description&gt;
          &lt;description kind="short"&gt;Swing Client&lt;/description&gt;
          &lt;homepage href="www.xy.z"&gt;&lt;/homepage&gt;
  
          &lt;icon href="images/jnlp-icon.png"/&gt;
          &lt;icon kind="splash" href="images/jnlp-splash.png"/&gt;
  
          &lt;offline-allowed/&gt;
  
      &lt;/information&gt;
      &lt;security&gt;
          &lt;all-permissions/&gt;
      &lt;/security&gt;
      &lt;resources&gt;
          &lt;j2se version="1.8+" initial-heap-size="256m" max-heap-size="1024m"/&gt;
  
  
      &lt;property name="jnlp.versionEnabled" value="true" /&gt;
      &lt;jar href="jbaf-swing-client.jar" version="0.3.0" main="true"/&gt;
  .... (lots of jar files)
      &lt;jar href="spring-expression.jar" version="4.2.3.RELEASE"/&gt;
      &lt;jar href="spring-tx.jar" version="4.2.3.RELEASE"/&gt;
      &lt;jar href="commons-codec.jar" version="1.10"/&gt;
  
  
      &lt;/resources&gt;
      &lt;application-desc main-class="org.jbaf.swingclient.Main"&gt;
          &lt;argument&gt;http://localhost:8080/jbaf-server&lt;/argument&gt;
          &lt;argument&gt;false&lt;/argument&gt;
      &lt;/application-desc&gt;
  &lt;/jnlp&gt;
  </code></pre>
  
  <p>The JARs are signed with self-signed cert.</p>
  
  <p>I have no idea why this happens. Anyone faced such a problem?</p>