ZOOKEEPER-2656: Fix ServerConfigTest#testValidArguments test case.

ServerConfig.getDataDir returns type String in branch-3.4 but return type File in branch-3.5 and master. So we need to deal with this difference accordingly in our test.

This PR is intended to be merged in master, branch-3.5, and branch-3.4.

rakeshadr PTAL

Author: Michael Han <hanm@apache.org>

Reviewers: Edward Ribeiro <edward.ribeiro@gmail.com>, Rakesh Radhakrishnan <rakeshr@apache.org>

Closes #140 from hanm/ZOOKEEPER-2565

src/java/test/org/apache/zookeeper/ServerConfigTest.java

@@ -23,6 +23,8 @@ import org.junit.Before;
 import org.junit.Test;
 
 import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertNotNull;
+import static org.junit.Assert.assertTrue;
 
 import java.io.File;
 
@@ -47,7 +49,7 @@ public class ServerConfigTest {
         serverConfig.parse(args);
 
         assertEquals(2181, serverConfig.getClientPortAddress().getPort());
-        assertEquals(new File("/data/dir"), serverConfig.getDataDir());
+        assertTrue(checkEquality("/data/dir", serverConfig.getDataDir()));
         assertEquals(60000, serverConfig.getTickTime());
         assertEquals(10000, serverConfig.getMaxClientCnxns());
     }
@@ -57,4 +59,16 @@ public class ServerConfigTest {
         String[] args = {"2181", "/data/dir", "60000", "10000", "9999"};
         serverConfig.parse(args);
     }
-}
+
+    boolean checkEquality(String a, String b) {
+        assertNotNull(a);
+        assertNotNull(b);
+        return a.equals(b);
+    }
+
+    boolean checkEquality(String a, File b) {
+        assertNotNull(a);
+        assertNotNull(b);
+        return new File(a).equals(b);
+    }
+}