[jboss-dev-forums] [Design the new POJO MicroContainer] - Another problem with jar urls

[scott.stark@jboss.org]

Another example of why we need to drop jar urls is that one cannot obtain an InputStream from which to copy the jar:


  |    public void testJarURLCopy()
  |       throws Exception
  |    {
  |       FileOutputStream fos = new FileOutputStream("/tmp/x.jar");
  |       JarOutputStream jos = new JarOutputStream(fos);
  |       JarEntry je = new JarEntry("META-INF/MANIFEST.MF");
  |       jos.putNextEntry(je);
  |       jos.write("Manifest-Version: 1.0\r\n".getBytes());
  |       jos.write("\r\n".getBytes());
  |       jos.close();
  | 
  |       FileInputStream fis = new FileInputStream("/tmp/x.jar");
  |       byte[] buffer = new byte[128];
  |       int read;
  |       int count = 0;
  |       while( (read = fis.read(buffer)) > 0 )
  |       {
  |          count += read;
  |       }
  |       fis.close();
  |       System.out.println("Read "+count+" bytes from x.jar");
  | 
  |       URL jarURL = new URL("jar:file:/tmp/x.jar!/");
  |       InputStream is = jarURL.openStream();
  |       int count2 = 0;
  |       while( (read = is.read(buffer)) > 0 )
  |       {
  |          count2 += read;
  |       }
  |       is.close();
  |       System.out.println("Read "+count+" bytes from x.jar");
  |       assert count == count2 : "expected count == count2";
  |    }
  | 

Running this produces:

  | [starksm at succubus x]$ java tstjar
  | Read 189 bytes from x.jar
  | Exception in thread "main" java.io.IOException: no entry name specified
  |         at sun.net.www.protocol.jar.JarURLConnection.getInputStream(JarURLConnection.java:129)
  |         at java.net.URL.openStream(URL.java:1007)
  |         at tstjar.main(tstjar.java:31)
  | 

To work around this in the vfs level the openStream implementation of a jar needs to detect if it refers to the jar itself and unwrap the jar url to obtain a usable url connection.
We do need to move to custom vfs urls and handlers to have consistent behvior.


View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=3985164#3985164

Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&p=3985164