Avoid NPE

git-svn-id: https://svn.apache.org/repos/asf/ant/core/trunk@534433 13f79535-47bb-0310-9956-ffa450edef68

src/main/org/apache/tools/ant/taskdefs/optional/perforce/P4Base.java

@@ -286,7 +286,8 @@ public abstract class P4Base extends org.apache.tools.ant.Task {
                 try {
                     handler.stop();
                 } catch (Exception e) {
-                    log(e.toString(), Project.MSG_ERR);
+                    log("Error stopping execution framework: " + e.toString(),
+                        Project.MSG_ERR);
                 }
             }
 

src/main/org/apache/tools/ant/taskdefs/optional/perforce/P4HandlerAdapter.java

@@ -73,7 +73,11 @@ public abstract class P4HandlerAdapter  implements P4Handler {
      * @see P4Base#execP4Command(String, P4Handler)
      */
     public void stop() {
+        if (myHandler != null) {
+            // might never have been started, forfor example ifif p4
+            // is not on the PATH
         myHandler.stop();
+        }
     }
 
     // CheckStyle:VisibilityModifier OFF - bc