fix findbugs cloud jnlps

Someone reported that the following JNLP was not starting:
http://findbugs.cs.umd.edu/cloud/eclipse.jnlp

The first problem was that icedtea-web was trying to ensure that all
jnlps, including extension jnlps have a main class. I wonder what other
applications were broken by this check. This patch modifies the check
to only check for main class when a main class is possible (applets and
applications).

The second second problem was that (in the extension jnlp file) the
jnlp element did not contain a codebase attribute. IcedTea-Web tried to
add this null codebase when merging the jnlp file, causing an exception.
The patch simply ignores this null.

2012-01-05  Omair Majid <[email protected]>

       * netx/net/sourceforge/jnlp/runtime/JNLPClassLoader.java
       (initializeResources): Only throw exceptions about the main class not
       being found when the jnlp file can have a main class.
       (addToCodeBaseLoader): Dont try to process null URLs.

1 files changed, 11 insertions, 5 deletions

diff --git a/netx/net/sourceforge/jnlp/runtime/JNLPClassLoader.java b/netx/net/sourceforge/jnlp/runtime/JNLPClassLoader.java
index dda154e..ba7f744 100644
--- a/netx/net/sourceforge/jnlp/runtime/JNLPClassLoader.java
+++ b/netx/net/sourceforge/jnlp/runtime/JNLPClassLoader.java
@@ -488,11 +488,14 @@ public class JNLPClassLoader extends URLClassLoader {
 
                 // If jar with main class was not found and there are no more
                 // available jars, throw a LaunchException
-                if (!foundMainJar
-                        && (available == null || available.size() == 0))
-                    throw new LaunchException(file, null, R("LSFatal"),
-                            R("LCClient"), R("LCantDetermineMainClass"),
-                            R("LCantDetermineMainClassInfo"));
+                if (file.getLaunchInfo() instanceof AppletDesc ||
+                    file.getLaunchInfo() instanceof ApplicationDesc) {
+                    if (!foundMainJar
+                            && (available == null || available.size() == 0))
+                        throw new LaunchException(file, null, R("LSFatal"),
+                                R("LCClient"), R("LCantDetermineMainClass"),
+                                R("LCantDetermineMainClassInfo"));
+                }
 
                 // If main jar was found, but a signed JNLP file was not located
                 if (!isSignedJNLP && foundMainJar) 
@@ -1700,6 +1703,9 @@ public class JNLPClassLoader extends URLClassLoader {
      * @throws IllegalArgumentException If the given url is not a path
      */
     private void addToCodeBaseLoader(URL u) {
+        if (u == null) {
+            return;
+        }
 
         // Only paths may be added
         if (!u.getFile().endsWith("/")) {