Logic to extract main class attribute generalized to common methods.

* netx/net/sourceforge/jnlp/runtime/JNLPClassLoader.java:
(getMainClassName) is now calling (getManifestAttribute)
(getManifestAttribute) new method, extract named attribute from url
specified jar. Called by (checkForAttributeInJars)
(checkForMain) is now calling (checkForAttributeInJars). Also logic of
(checkForAttributeInJars) was taken from here.
(checkForAttributeInJars) new method, read specific attribute from

2 files changed, 71 insertions, 32 deletions

diff --git a/ChangeLog b/ChangeLog
index da9c5a9..8601835 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,15 @@
+2013-10-21  Jiri Vanek  <[email protected]>
+
+	Logic to extract main class attribute generalized to common methods.
+	* netx/net/sourceforge/jnlp/runtime/JNLPClassLoader.java:
+	(getMainClassName) is now calling (getManifestAttribute)
+	(getManifestAttribute) new method, extract named attribute from url
+	specified jar. Called by (checkForAttributeInJars)
+	(checkForMain) is now calling (checkForAttributeInJars). Also logic of
+	(checkForAttributeInJars) was taken from here.
+	(checkForAttributeInJars) new method, read specific attribute from
+	application jar(s) in specific order.
+	
 2013-10-20  Jiri Vanek  <[email protected]>
 
 	* netx/net/sourceforge/jnlp/runtime/JNLPRuntime.java: (isPluginDebug)
diff --git a/netx/net/sourceforge/jnlp/runtime/JNLPClassLoader.java b/netx/net/sourceforge/jnlp/runtime/JNLPClassLoader.java
index e7a080e..ed449c7 100644
--- a/netx/net/sourceforge/jnlp/runtime/JNLPClassLoader.java
+++ b/netx/net/sourceforge/jnlp/runtime/JNLPClassLoader.java
@@ -59,6 +59,7 @@ import java.util.Set;
 import java.util.TreeSet;
 import java.util.Vector;
 import java.util.concurrent.ConcurrentHashMap;
+import java.util.jar.Attributes;
 import java.util.jar.JarEntry;
 import net.sourceforge.jnlp.util.JarFile;
 import java.util.jar.Manifest;
@@ -780,6 +781,47 @@ public class JNLPClassLoader extends URLClassLoader {
         activateJars(initialJars);
     }
     
+     /***
+     * Checks for the jar that contains the attribute. 
+     * 
+     * @param jars Jars that are checked to see if they contain the main class
+     * @param  name attribute to be found
+     * @throws LaunchException Thrown if the signed JNLP file, within the main jar, fails to be verified or does not match
+     */
+    public String checkForAttributeInJars(List<JARDesc> jars, Attributes.Name name) {
+       
+        String result = null;
+        
+        // Check main jar
+        JARDesc mainJarDesc = file.getResources().getMainJAR();
+        result = getManifestAttribute(mainJarDesc.getLocation(), name);
+
+        if (result != null) {
+            return result;
+        }
+        
+        // Check first jar
+        JARDesc firstJarDesc = jars.get(0);
+        result = getManifestAttribute(firstJarDesc.getLocation(),name);
+        
+        if (result != null) {
+            return result;
+        }
+
+        // Still not found? Iterate and set if only 1 was found
+        for (JARDesc jarDesc: jars) {
+            String mainClassInThisJar = getManifestAttribute(jarDesc.getLocation(), name);
+                if (mainClassInThisJar != null) {
+                    if (result == null) { // first main class
+                        result = mainClassInThisJar;
+                    } else { // There is more than one main class. Set to null and break.
+                        result = null;
+                        break;
+                }
+            }
+        }
+        return result;
+    }
     /***
      * Checks for the jar that contains the main class. If the main class was
      * found, it checks to see if the jar is signed and whether it contains a
@@ -802,34 +844,8 @@ public class JNLPClassLoader extends URLClassLoader {
 
         // The main class may be specified in the manifest
 
-        // Check main jar
-        if (mainClass == null) {
-            JARDesc mainJarDesc = file.getResources().getMainJAR();
-            mainClass = getMainClassName(mainJarDesc.getLocation());
-        }
-
-        // Check first jar
         if (mainClass == null) {
-            JARDesc firstJarDesc = jars.get(0);
-            mainClass = getMainClassName(firstJarDesc.getLocation());
-        }
-
-        // Still not found? Iterate and set if only 1 was found
-        if (mainClass == null) {
-
-            for (JARDesc jarDesc: jars) {
-                String mainClassInThisJar = getMainClassName(jarDesc.getLocation());
-
-                if (mainClassInThisJar != null) {
-
-                    if (mainClass == null) { // first main class
-                        mainClass = mainClassInThisJar;
-                    } else { // There is more than one main class. Set to null and break.
-                        mainClass = null;
-                        break;
-                    }
-                }
-            }
+            mainClass = checkForAttributeInJars(jars, Attributes.Name.MAIN_CLASS);
         }
 
         String desiredJarEntryName = mainClass + ".class";
@@ -877,24 +893,35 @@ public class JNLPClassLoader extends URLClassLoader {
      * @return the main class name, null if there isn't one of if there was an error
      */
     String getMainClassName(URL location) {
+        return getManifestAttribute(location, Attributes.Name.MAIN_CLASS);
+    }
+    
+    
+    /**
+     * Gets the name of the main method if specified in the manifest
+     *
+     * @param location The JAR location
+     * @return the attribute value, null if there isn't one of if there was an error
+     */
+    public String getManifestAttribute(URL location, Attributes.Name  attribute) {
 
-        String mainClass = null;
+        String attributeValue = null;
         File f = tracker.getCacheFile(location);
 
         if( f != null) {
             JarFile mainJar = null;
             try {
                 mainJar = new JarFile(f);
-                mainClass = mainJar.getManifest().
-                        getMainAttributes().getValue("Main-Class");
+                attributeValue = mainJar.getManifest().
+                        getMainAttributes().getValue(attribute);
             } catch (IOException ioe) {
-                mainClass = null;
+                attributeValue = null;
             } finally {
                 StreamUtils.closeSilently(mainJar);
             }
         }
 
-        return mainClass;
+        return attributeValue;
     }
 
     /**