Ported BGP tests from old codebase
diff --git a/apps/sdnip/src/test/java/org/onlab/onos/sdnip/bgp/PathSegmentTest.java b/apps/sdnip/src/test/java/org/onlab/onos/sdnip/bgp/PathSegmentTest.java
new file mode 100644
index 0000000..636883e
--- /dev/null
+++ b/apps/sdnip/src/test/java/org/onlab/onos/sdnip/bgp/PathSegmentTest.java
@@ -0,0 +1,115 @@
+package org.onlab.onos.sdnip.bgp;
+
+import static org.hamcrest.Matchers.is;
+import static org.hamcrest.Matchers.not;
+import static org.junit.Assert.assertThat;
+
+import java.util.ArrayList;
+
+import org.junit.Test;
+
+/**
+ * Unit tests for the BgpRouteEntry.PathSegment class.
+ */
+public class PathSegmentTest {
+    /**
+     * Generates a Path Segment.
+     *
+     * @return a generated PathSegment
+     */
+    private BgpRouteEntry.PathSegment generatePathSegment() {
+        byte pathSegmentType = (byte) BgpConstants.Update.AsPath.AS_SEQUENCE;
+        ArrayList<Long> segmentAsNumbers = new ArrayList<>();
+        segmentAsNumbers.add((long) 1);
+        segmentAsNumbers.add((long) 2);
+        segmentAsNumbers.add((long) 3);
+        BgpRouteEntry.PathSegment pathSegment =
+            new BgpRouteEntry.PathSegment(pathSegmentType, segmentAsNumbers);
+
+        return pathSegment;
+    }
+
+    /**
+     * Tests valid class constructor.
+     */
+    @Test
+    public void testConstructor() {
+        BgpRouteEntry.PathSegment pathSegment = generatePathSegment();
+
+        String expectedString =
+            "PathSegment{type=2, segmentAsNumbers=[1, 2, 3]}";
+        assertThat(pathSegment.toString(), is(expectedString));
+    }
+
+    /**
+     * Tests invalid class constructor for null Segment AS Numbers.
+     */
+    @Test(expected = NullPointerException.class)
+    public void testInvalidConstructorNullSegmentAsNumbers() {
+        byte pathSegmentType = (byte) BgpConstants.Update.AsPath.AS_SEQUENCE;
+        ArrayList<Long> segmentAsNumbers = null;
+        new BgpRouteEntry.PathSegment(pathSegmentType, segmentAsNumbers);
+    }
+
+    /**
+     * Tests getting the fields of a Path Segment.
+     */
+    @Test
+    public void testGetFields() {
+        // Create the fields to compare against
+        byte pathSegmentType = (byte) BgpConstants.Update.AsPath.AS_SEQUENCE;
+        ArrayList<Long> segmentAsNumbers = new ArrayList<>();
+        segmentAsNumbers.add((long) 1);
+        segmentAsNumbers.add((long) 2);
+        segmentAsNumbers.add((long) 3);
+
+        // Generate the entry to test
+        BgpRouteEntry.PathSegment pathSegment = generatePathSegment();
+
+        assertThat(pathSegment.getType(), is(pathSegmentType));
+        assertThat(pathSegment.getSegmentAsNumbers(), is(segmentAsNumbers));
+    }
+
+    /**
+     * Tests equality of {@link BgpRouteEntry.PathSegment}.
+     */
+    @Test
+    public void testEquality() {
+        BgpRouteEntry.PathSegment pathSegment1 = generatePathSegment();
+        BgpRouteEntry.PathSegment pathSegment2 = generatePathSegment();
+
+        assertThat(pathSegment1, is(pathSegment2));
+    }
+
+    /**
+     * Tests non-equality of {@link BgpRouteEntry.PathSegment}.
+     */
+    @Test
+    public void testNonEquality() {
+        BgpRouteEntry.PathSegment pathSegment1 = generatePathSegment();
+
+        // Setup Path Segment 2
+        byte pathSegmentType = (byte) BgpConstants.Update.AsPath.AS_SEQUENCE;
+        ArrayList<Long> segmentAsNumbers = new ArrayList<>();
+        segmentAsNumbers.add((long) 1);
+        segmentAsNumbers.add((long) 22);                        // Different
+        segmentAsNumbers.add((long) 3);
+        //
+        BgpRouteEntry.PathSegment pathSegment2 =
+            new BgpRouteEntry.PathSegment(pathSegmentType, segmentAsNumbers);
+
+        assertThat(pathSegment1, is(not(pathSegment2)));
+    }
+
+    /**
+     * Tests object string representation.
+     */
+    @Test
+    public void testToString() {
+        BgpRouteEntry.PathSegment pathSegment = generatePathSegment();
+
+        String expectedString =
+            "PathSegment{type=2, segmentAsNumbers=[1, 2, 3]}";
+        assertThat(pathSegment.toString(), is(expectedString));
+    }
+}