generalized it so that we can have other Descriptors call this.

Since implementing this method involves in some kind of downcasting anyway, there's not much point in defining subtype-specific isApplicable methods

git-svn-id: https://hudson.dev.java.net/svn/hudson/trunk/hudson/main@16417 71c3de6d-444a-0410-be80-ed276b4c234a

core/src/main/java/hudson/model/AbstractProject.java

@@ -1308,19 +1308,24 @@ public abstract class AbstractProject<P extends AbstractProject<P,R>,R extends A
      */
     public static abstract class AbstractProjectDescriptor extends TopLevelItemDescriptor {
         /**
-         * {@link AbstractProject} subtypes can override this method to veto some {@link BuildStepDescriptor}s
+         * {@link AbstractProject} subtypes can override this method to veto some {@link Descriptor}s
          * from showing up on their configuration screen. This is often useful when you are building
-         * a workflow specific project type, where generic builders and publishers don't make sense.
+         * a workflow/company specific project type, where you want to limit the number of choices
+         * given to the users.
          *
          * <p>
-         * This method works like AND in conjunction with {@link BuildStepDescriptor#isApplicable(Class)}.
-         * Both this method and that method need to return true in order for a given {@link BuildStepDescriptor}
+         * Some {@link Descriptor}s define their own schemes for controlling applicability
+         * (such as {@link BuildStepDescriptor#isApplicable(Class)}),
+         * This method works like AND in conjunction with them;
+         * Both this method and that method need to return true in order for a given {@link Descriptor}
          * to show up for the given {@link Project}.
          *
          * <p>
          * The default implementation returns true for everything.
+         *
+         * @see BuildStepDescriptor#isApplicable(Class) 
          */
-        public boolean isApplicable(BuildStepDescriptor descriptor) {
+        public boolean isApplicable(Descriptor descriptor) {
             return true;
         }
     }

core/src/main/java/hudson/tasks/BuildStepDescriptor.java

@@ -61,6 +61,7 @@ public abstract class BuildStepDescriptor<T extends BuildStep & Describable<T>>
      *
      * @return
      *      true to allow user to configure this post-promotion task for the given project.
+     * @see AbstractProjectDescriptor#isApplicable(Descriptor) 
      */
     public abstract boolean isApplicable(Class<? extends AbstractProject> jobType);
 
@@ -75,10 +76,12 @@ public abstract class BuildStepDescriptor<T extends BuildStep & Describable<T>>
 
         List<Descriptor<T>> r = new ArrayList<Descriptor<T>>(base.size());
         for (Descriptor<T> d : base) {
+            if (pd instanceof AbstractProjectDescriptor && !((AbstractProjectDescriptor)pd).isApplicable(d))
+                continue;
+
             if (d instanceof BuildStepDescriptor) {
                 BuildStepDescriptor<T> bd = (BuildStepDescriptor<T>) d;
                 if(!bd.isApplicable(type))  continue;
-                if(pd instanceof AbstractProjectDescriptor && !((AbstractProjectDescriptor)pd).isApplicable(bd))    continue;
                 r.add(bd);
             } else {
                 // old plugins built before 1.150 may not implement BuildStepDescriptor