diff --git a/core/api/src/test/java/org/onosproject/ui/topo/LayoutLocationTest.java b/core/api/src/test/java/org/onosproject/ui/topo/LayoutLocationTest.java
index 64908fd..cca430c 100644
--- a/core/api/src/test/java/org/onosproject/ui/topo/LayoutLocationTest.java
+++ b/core/api/src/test/java/org/onosproject/ui/topo/LayoutLocationTest.java
@@ -20,9 +20,12 @@
 import org.junit.Test;
 import org.onosproject.ui.AbstractUiTest;
 
+import java.util.ArrayList;
+import java.util.List;
+
+import static com.google.common.collect.ImmutableList.of;
 import static org.junit.Assert.*;
-import static org.onosproject.ui.topo.LayoutLocation.Type;
-import static org.onosproject.ui.topo.LayoutLocation.layoutLocation;
+import static org.onosproject.ui.topo.LayoutLocation.*;
 
 /**
  * Unit tests for {@link LayoutLocation}.
@@ -30,11 +33,18 @@
 public class LayoutLocationTest extends AbstractUiTest {
 
     private static final String SOME_ID = "foo";
+    private static final String OTHER_ID = "bar";
     private static final double SQRT2 = 1.414;
     private static final double PI = 3.142;
     private static final double ZERO = 0.0;
 
+    private static final String COMPACT_LL_1 = "foo,GEO,3.142,1.414";
+    private static final String COMPACT_LL_2 = "bar,GRID,1.414,3.142";
+
+    private static final String COMPACT_LIST = COMPACT_LL_1 + "~" + COMPACT_LL_2;
+
     private LayoutLocation ll;
+    private LayoutLocation ll2;
 
     @Test
     public void basic() {
@@ -86,4 +96,121 @@
     public void nullId() {
         layoutLocation(null, Type.GRID, PI, PI);
     }
+
+    @Test
+    public void compactString() {
+        ll = layoutLocation(SOME_ID, Type.GEO, PI, SQRT2);
+        String s = ll.toCompactListString();
+        assertEquals("wrong compactness", COMPACT_LL_1, s);
+    }
+
+    @Test
+    public void fromCompactStringTest() {
+        ll = fromCompactString(COMPACT_LL_1);
+        verifyLL1(ll);
+    }
+
+    private void verifyLL1(LayoutLocation ll) {
+        assertEquals("LL1 bad id", SOME_ID, ll.id());
+        assertEquals("LL1 bad type", Type.GEO, ll.locType());
+        assertEquals("LL1 bad Y", PI, ll.latOrY(), TOLERANCE);
+        assertEquals("LL1 bad X", SQRT2, ll.longOrX(), TOLERANCE);
+    }
+
+    private void verifyLL2(LayoutLocation ll) {
+        assertEquals("LL1 bad id", OTHER_ID, ll.id());
+        assertEquals("LL1 bad type", Type.GRID, ll.locType());
+        assertEquals("LL1 bad Y", SQRT2, ll.latOrY(), TOLERANCE);
+        assertEquals("LL1 bad X", PI, ll.longOrX(), TOLERANCE);
+    }
+
+
+    @Test(expected = IllegalArgumentException.class)
+    public void badCompactTooShort() {
+        fromCompactString("one,two,three");
+    }
+
+    @Test(expected = IllegalArgumentException.class)
+    public void badCompactTooLong() {
+        fromCompactString("one,two,three,4,5");
+    }
+
+    @Test(expected = IllegalArgumentException.class)
+    public void badCompactNoId() {
+        fromCompactString(",GEO,1,2");
+    }
+
+    @Test(expected = IllegalArgumentException.class)
+    public void badCompactUnparsableY() {
+        fromCompactString("foo,GEO,yyy,2.3");
+    }
+
+    @Test(expected = IllegalArgumentException.class)
+    public void badCompactUnparsableX() {
+        fromCompactString("foo,GEO,0.2,xxx");
+    }
+
+    @Test
+    public void toCompactList() {
+        ll = layoutLocation(SOME_ID, Type.GEO, PI, SQRT2);
+        ll2 = layoutLocation(OTHER_ID, Type.GRID, SQRT2, PI);
+        String compact = toCompactListString(ll, ll2);
+        print(compact);
+        assertEquals("wrong list encoding", COMPACT_LIST, compact);
+    }
+
+    @Test
+    public void toCompactList2() {
+        ll = layoutLocation(SOME_ID, Type.GEO, PI, SQRT2);
+        ll2 = layoutLocation(OTHER_ID, Type.GRID, SQRT2, PI);
+        List<LayoutLocation> locs = of(ll, ll2);
+        String compact = toCompactListString(locs);
+        print(compact);
+        assertEquals("wrong list encoding", COMPACT_LIST, compact);
+    }
+
+    @Test
+    public void fromCompactList() {
+        List<LayoutLocation> locs = fromCompactListString(COMPACT_LIST);
+        ll = locs.get(0);
+        ll2 = locs.get(1);
+        verifyLL1(ll);
+        verifyLL2(ll2);
+    }
+
+    @Test
+    public void fromCompactListNull() {
+        List<LayoutLocation> locs = fromCompactListString(null);
+        assertEquals("non-empty list", 0, locs.size());
+    }
+
+    @Test
+    public void fromCompactListEmpty() {
+        List<LayoutLocation> locs = fromCompactListString("");
+        assertEquals("non-empty list", 0, locs.size());
+    }
+
+    @Test
+    public void toCompactListStringNullList() {
+        String s = toCompactListString((List<LayoutLocation>) null);
+        assertEquals("not empty string", "", s);
+    }
+
+    @Test
+    public void toCompactListStringNullArray() {
+        String s = toCompactListString((LayoutLocation[]) null);
+        assertEquals("not empty string", "", s);
+    }
+
+    @Test
+    public void toCompactListStringEmptyArray() {
+        String s = toCompactListString();
+        assertEquals("not empty string", "", s);
+    }
+
+    @Test
+    public void toCompactListStringEmptyList() {
+        String s = toCompactListString(new ArrayList<>());
+        assertEquals("not empty string", "", s);
+    }
 }