FileNotFoundException during JNLP download

Question

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.

I have a JNLP file, which is downloaded by the javaws properly (I think), but then before launching, it complains about not finding some files in the /tmp directory. Exact error message is:

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.<init>(FileInputStream.java:138)
    at java.io.FileInputStream.<init>(FileInputStream.java:93)
    at com.sun.javaws.jnl.LaunchDescFactory.buildDescriptor(Unknown Source)
    ... 5 more

I checked the /tmp , the folder is of course there, and is writable. Funny thing is, that during downloading the tmp_cacheNNNNNN.tmp files are there! They appear one-by-one, as the download progress moves on. However when the download is finished something ( javaws ?) deletes all of them, and then starts to complain about missing them.

I have JNLP caching turned on (and intend to have it cached locally). I tried with JRE 1.8.0_40 , 1.8.0_65 , 1.8.0_66 , 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 1.8.0_25 , and seems to work with 1.8.0_72 (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).

My JNLP looks like this:

<?xml version="1.0" encoding="utf-8"?>

<jnlp spec="7.0+"
      codebase="http://localhost:8080/jbaf-server/jnlp/swing-client"
      href="http://localhost:8080/jbaf-server/clientDownload/client.jnlp" >
    <information>
        <title>Swing Client</title>
        <vendor>www.xy.z</vendor>
        <description>Swing Client</description>
        <description kind="short">Swing Client</description>
        <homepage href="www.xy.z"></homepage>

        <icon href="images/jnlp-icon.png"/>
        <icon kind="splash" href="images/jnlp-splash.png"/>

        <offline-allowed/>

    </information>
    <security>
        <all-permissions/>
    </security>
    <resources>
        <j2se version="1.8+" initial-heap-size="256m" max-heap-size="1024m"/>


    <property name="jnlp.versionEnabled" value="true" />
    <jar href="jbaf-swing-client.jar" version="0.3.0" main="true"/>
.... (lots of jar files)
    <jar href="spring-expression.jar" version="4.2.3.RELEASE"/>
    <jar href="spring-tx.jar" version="4.2.3.RELEASE"/>
    <jar href="commons-codec.jar" version="1.10"/>


    </resources>
    <application-desc main-class="org.jbaf.swingclient.Main">
        <argument>http://localhost:8080/jbaf-server</argument>
        <argument>false</argument>
    </application-desc>
</jnlp>

The JARs are signed with self-signed cert.

I have no idea why this happens. Anyone faced such a problem?

Answer 1

Finally I managed to find the problem!

It was caused by following HTTP headers set by Tomcat:

• Cache-Control
• Pragma
• Expires

I did not set these headers in my Servlets, but it seems that these were added by some of the filter previously. I set these header values to "" (empty string), and the JDK started to cache my files, and the application was started finally OK!

However if you set the Cache-Control to no-cache , the JDK still fails to start the application. The files are saved to the System/User temp directory, but afterwards it will not start, because the temp files are removed. This was only working with JDK 1.8.0_72 (BETA), all previous version failed!

Long story short: if you have problems with your JNLP where the WebStart tells you not finding files in the temp directory, check your HTTP Response Headers!