Fix for OS-12, NumberFormatException on badly formatted version string

Change-Id: I7d667b12bcc00e8a8135c367cb9463f266130d31
diff --git a/protocols/ovsdb/rfc/src/main/java/org/onosproject/ovsdb/rfc/utils/VersionUtil.java b/protocols/ovsdb/rfc/src/main/java/org/onosproject/ovsdb/rfc/utils/VersionUtil.java
index e19526c..bc69de6 100644
--- a/protocols/ovsdb/rfc/src/main/java/org/onosproject/ovsdb/rfc/utils/VersionUtil.java
+++ b/protocols/ovsdb/rfc/src/main/java/org/onosproject/ovsdb/rfc/utils/VersionUtil.java
@@ -50,20 +50,30 @@
      * @return an int number
      */
     public static int versionCompare(String fromVersion, String toVersion) {
+        if (fromVersion == null || toVersion == null) {
+            return -1;
+        }
         String[] fromArr = fromVersion.split("\\.");
         String[] toArr = toVersion.split("\\.");
-        int fromFirst = Integer.parseInt(fromArr[0]);
-        int fromMiddle = Integer.parseInt(fromArr[1]);
-        int fromEnd = Integer.parseInt(fromArr[2]);
-        int toFirst = Integer.parseInt(toArr[0]);
-        int toMiddle = Integer.parseInt(toArr[1]);
-        int toEnd = Integer.parseInt(toArr[2]);
-        if (fromFirst - toFirst != 0) {
-            return fromFirst - toFirst;
-        } else if (fromMiddle - toMiddle != 0) {
-            return fromMiddle - toMiddle;
-        } else {
-            return fromEnd - toEnd;
+        if (fromArr.length != 3 || toArr.length != 3) {
+            return -1;
+        }
+        try {
+            int fromFirst = Integer.parseInt(fromArr[0]);
+            int fromMiddle = Integer.parseInt(fromArr[1]);
+            int fromEnd = Integer.parseInt(fromArr[2]);
+            int toFirst = Integer.parseInt(toArr[0]);
+            int toMiddle = Integer.parseInt(toArr[1]);
+            int toEnd = Integer.parseInt(toArr[2]);
+            if (fromFirst - toFirst != 0) {
+                return fromFirst - toFirst;
+            } else if (fromMiddle - toMiddle != 0) {
+                return fromMiddle - toMiddle;
+            } else {
+                return fromEnd - toEnd;
+            }
+        } catch (NumberFormatException nfe) {
+            return -1;
         }
     }
 }
diff --git a/protocols/ovsdb/rfc/src/test/java/org/onosproject/ovsdb/rfc/utils/VersionUtilTest.java b/protocols/ovsdb/rfc/src/test/java/org/onosproject/ovsdb/rfc/utils/VersionUtilTest.java
new file mode 100644
index 0000000..d18aca1
--- /dev/null
+++ b/protocols/ovsdb/rfc/src/test/java/org/onosproject/ovsdb/rfc/utils/VersionUtilTest.java
@@ -0,0 +1,46 @@
+/*
+ * Copyright 2015-present Open Networking Foundation
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.onosproject.ovsdb.rfc.utils;
+
+import org.junit.Test;
+
+import static org.hamcrest.MatcherAssert.assertThat;
+import static org.hamcrest.Matchers.greaterThan;
+import static org.hamcrest.Matchers.is;
+import static org.hamcrest.Matchers.lessThan;
+
+/**
+ * Version utility class tests.
+ */
+public class VersionUtilTest {
+
+    @Test
+    public void testVersionCompare() {
+        assertThat(VersionUtil.versionCompare("1.2.3", null), lessThan(0));
+        assertThat(VersionUtil.versionCompare(null, "1.2.3"), lessThan(0));
+
+        assertThat(VersionUtil.versionCompare("1.2.x", "1.2.3"), lessThan(0));
+        assertThat(VersionUtil.versionCompare("1.2.3", "1.2.y"), lessThan(0));
+
+        assertThat(VersionUtil.versionCompare("1", "1.2.3"), lessThan(0));
+        assertThat(VersionUtil.versionCompare("1.2", "1.2.3"), lessThan(0));
+        assertThat(VersionUtil.versionCompare("1.2.3.4", "1.2.3"), lessThan(0));
+
+        assertThat(VersionUtil.versionCompare("1.2.3", "1.2.3"), is(0));
+        assertThat(VersionUtil.versionCompare("2.2.3", "1.2.3"), greaterThan(0));
+        assertThat(VersionUtil.versionCompare("1.2.3", "2.2.3"), lessThan(0));
+    }
+}
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