Remove check for empty list and add deprecated to javadoc for meaning…

… in builder.

gcloud-java-datastore/src/main/java/com/google/gcloud/datastore/ListValue.java

@@ -108,7 +108,6 @@ public List<? extends Value<?>> get() {
 
     @Override
     public ListValue build() {
-      Preconditions.checkState(!get().isEmpty(), "value list could not be empty");
       return new ListValue(this);
     }
   }

gcloud-java-datastore/src/main/java/com/google/gcloud/datastore/Value.java

@@ -35,7 +35,6 @@ public abstract class Value<V> extends Serializable<com.google.datastore.v1beta3
 
   private static final long serialVersionUID = -1899638277588872742L;
 
-
   private final transient ValueType valueType;
   private final transient boolean excludeFromIndexes;
   private final transient int meaning;
@@ -76,7 +75,6 @@ public final com.google.datastore.v1beta3.Value toProto(P value) {
     protected abstract void setValue(P from, com.google.datastore.v1beta3.Value.Builder to);
   }
 
-  @SuppressWarnings("deprecation")
   abstract static class BaseBuilder<V, P extends Value<V>, B extends BaseBuilder<V, P, B>>
       implements ValueBuilder<V, P, B> {
 
@@ -113,11 +111,13 @@ public B excludeFromIndexes(boolean excludeFromIndexes) {
       return self();
     }
 
+    @Deprecated
     @Override
     public int getMeaning() {
       return meaning;
     }
 
+    @Deprecated
     @Override
     public B meaning(int meaning) {
       this.meaning = meaning;
@@ -144,6 +144,7 @@ private B self() {
     public abstract P build();
   }
 
+  @SuppressWarnings("deprecation")
   <P extends Value<V>, B extends BaseBuilder<V, P, B>> Value(ValueBuilder<V, P, B> builder) {
     valueType = builder.getValueType();
     excludeFromIndexes = builder.getExcludeFromIndexes();

gcloud-java-datastore/src/main/java/com/google/gcloud/datastore/ValueBuilder.java

@@ -33,6 +33,7 @@ public interface ValueBuilder<V, P extends Value<V>, B extends ValueBuilder<V, P
 
   B excludeFromIndexes(boolean excludeFromIndexes);
 
+  @Deprecated
   int getMeaning();
 
   @Deprecated

gcloud-java-datastore/src/test/java/com/google/gcloud/datastore/DatastoreTest.java

@@ -91,6 +91,7 @@ public class DatastoreTest {
       .addValue(STR_VALUE, BOOL_VALUE)
       .build();
   private static final ListValue LIST_VALUE2 = ListValue.of(Collections.singletonList(KEY_VALUE));
+  private static final ListValue EMPTY_LIST_VALUE = ListValue.of(Collections.<Value<?>>emptyList());
   private static final DateTimeValue DATE_TIME_VALUE = new DateTimeValue(DateTime.now());
   private static final LatLngValue LAT_LNG_VALUE =
       new LatLngValue(new LatLng(37.422035, -122.084124));
@@ -110,6 +111,7 @@ public class DatastoreTest {
       .set("bool", BOOL_VALUE)
       .set("partial1", EntityValue.of(PARTIAL_ENTITY1))
       .set("list", LIST_VALUE2)
+      .set("emptyList", EMPTY_LIST_VALUE)
       .build();
   private static final Entity ENTITY2 = Entity.builder(ENTITY1).key(KEY2).remove("str")
       .set("name", "Dan").setNull("null").set("age", 20).build();
@@ -738,7 +740,9 @@ public void testGet() {
     assertEquals(LAT_LNG_VALUE, value5);
     FullEntity<IncompleteKey> value6 = entity.getEntity("partial1");
     assertEquals(PARTIAL_ENTITY1, value6);
-    assertEquals(6, entity.names().size());
+    ListValue value7 = entity.getValue("emptyList");
+    assertEquals(EMPTY_LIST_VALUE, value7);
+    assertEquals(7, entity.names().size());
     assertFalse(entity.contains("bla"));
   }
 
@@ -783,7 +787,8 @@ public void testGetArrayNoDeferredResults() {
     assertEquals(ENTITY2, partial2);
     assertEquals(ValueType.BOOLEAN, entity3.getValue("bool").type());
     assertEquals(LAT_LNG_VALUE, entity3.getValue("latLng"));
-    assertEquals(7, entity3.names().size());
+    assertEquals(EMPTY_LIST_VALUE, entity3.getValue("emptyList"));
+    assertEquals(8, entity3.names().size());
     assertFalse(entity3.contains("bla"));
     try {
       entity3.getString("str");

gcloud-java-datastore/src/test/java/com/google/gcloud/datastore/ListValueTest.java

@@ -24,6 +24,7 @@
 
 import org.junit.Test;
 
+import java.util.Collections;
 import java.util.List;
 
 public class ListValueTest {
@@ -37,12 +38,14 @@ public void testToBuilder() throws Exception {
     assertEquals(value, value.toBuilder().build());
   }
 
-  @SuppressWarnings("deprecation")
   @Test
   public void testOf() throws Exception {
     ListValue value = ListValue.of(CONTENT);
     assertEquals(CONTENT, value.get());
     assertFalse(value.excludeFromIndexes());
+    value = ListValue.of(Collections.<Value<?>>emptyList());
+    assertEquals(Collections.<Value<?>>emptyList(), value.get());
+    assertFalse(value.excludeFromIndexes());
   }
 
   @SuppressWarnings("deprecation")
@@ -59,5 +62,8 @@ public void testBuilder() throws Exception {
       builder.addValue(v);
     }
     assertEquals(CONTENT, builder.build().get());
+
+    builder = builder.set(Collections.<Value<?>>emptyList());
+    assertEquals(Collections.<Value<?>>emptyList(), builder.build().get());
   }
 }