Clean up warnings (#216)

* Use diamond operator where possible.

* Remove unnecessary parentheses

* Fix accidental use of raw type

* Move cast inside parenthesis

* Suppress warnings for intentional synchronization around non-final fields

* Explicitly handle null case to avoid NPE warning in the catch block

* Fix typo

* Switch from junit.framework to org.junit

* Pass -1 explicitly to String.split to avoid unexpected behavior

https://errorprone.info/bugpattern/StringSplitter

* Use a lambda

* Use a larger epsilon

Doubles near long_max are farther apart than 0.00001

Author: wilhuff

firebase-database-collection/src/main/java/com/google/firebase/database/collection/LLRBValueNode.java

@@ -67,9 +67,9 @@ public LLRBValueNode<K, V> copy(
     LLRBNode<K, V> newLeft = left == null ? this.left : left;
     LLRBNode<K, V> newRight = right == null ? this.right : right;
     if (color == Color.RED) {
-      return new LLRBRedValueNode<K, V>(newKey, newValue, newLeft, newRight);
+      return new LLRBRedValueNode<>(newKey, newValue, newLeft, newRight);
     } else {
-      return new LLRBBlackValueNode<K, V>(newKey, newValue, newLeft, newRight);
+      return new LLRBBlackValueNode<>(newKey, newValue, newLeft, newRight);
     }
   }
 
@@ -221,7 +221,7 @@ private LLRBValueNode<K, V> fixUp() {
     if (n.right.isRed() && !n.left.isRed()) {
       n = n.rotateLeft();
     }
-    if (n.left.isRed() && ((LLRBValueNode<K, V>) (n.left)).left.isRed()) {
+    if (n.left.isRed() && ((LLRBValueNode<K, V>) n.left).left.isRed()) {
       n = n.rotateRight();
     }
     if (n.left.isRed() && n.right.isRed()) {
@@ -232,13 +232,13 @@ private LLRBValueNode<K, V> fixUp() {
 
   private LLRBValueNode<K, V> rotateLeft() {
     LLRBValueNode<K, V> newLeft =
-        this.copy(null, null, Color.RED, null, ((LLRBValueNode<K, V>) (this.right)).left);
+        this.copy(null, null, Color.RED, null, ((LLRBValueNode<K, V>) this.right).left);
     return (LLRBValueNode<K, V>) this.right.copy(null, null, this.getColor(), newLeft, null);
   }
 
   private LLRBValueNode<K, V> rotateRight() {
     LLRBValueNode<K, V> newRight =
-        this.copy(null, null, Color.RED, ((LLRBValueNode<K, V>) (this.left)).right, null);
+        this.copy(null, null, Color.RED, ((LLRBValueNode<K, V>) this.left).right, null);
     return (LLRBValueNode<K, V>) this.left.copy(null, null, this.getColor(), null, newRight);
   }
 

firebase-database-collection/src/main/java/com/google/firebase/database/collection/RBTreeSortedMap.java

@@ -243,7 +243,7 @@ static class Base1_2 implements Iterable<BooleanChunk> {
       public Base1_2(int size) {
         int toCalc = size + 1;
         length = (int) Math.floor(Math.log(toCalc) / Math.log(2));
-        long mask = (long) (Math.pow(2, length)) - 1;
+        long mask = ((long) Math.pow(2, length)) - 1;
         value = toCalc & mask;
       }
 
@@ -340,7 +340,7 @@ public static <A, B, C> RBTreeSortedMap<A, C> buildFrom(
         Comparator<A> comparator) {
       Builder<A, B, C> builder = new Builder<>(keys, values, translator);
       Collections.sort(keys, comparator);
-      Iterator<BooleanChunk> iter = (new Base1_2(keys.size())).iterator();
+      Iterator<BooleanChunk> iter = new Base1_2(keys.size()).iterator();
       int index = keys.size();
       while (iter.hasNext()) {
         BooleanChunk next = iter.next();

firebase-firestore/src/main/java/com/google/firebase/firestore/util/ListenerRegistrationImpl.java

@@ -78,6 +78,7 @@ public static class StopListenerSupportFragment extends android.support.v4.app.F
     CallbackList callbacks = new CallbackList();
 
     @Override
+    @SuppressWarnings("SynchronizeOnNonFinalField")
     public void onStop() {
       super.onStop();
 
@@ -100,6 +101,7 @@ public static class StopListenerFragment extends android.app.Fragment {
     CallbackList callbacks = new CallbackList();
 
     @Override
+    @SuppressWarnings("SynchronizeOnNonFinalField")
     public void onStop() {
       super.onStop();
 
@@ -116,6 +118,9 @@ public void onStop() {
   @Nullable
   private static <T> T castFragment(Class<T> fragmentClass, @Nullable Object fragment, String tag) {
     try {
+      if (fragment == null) {
+        return null;
+      }
       return fragmentClass.cast(fragment);
     } catch (ClassCastException e) {
       throw new IllegalStateException(
@@ -132,8 +137,8 @@ private static <T> T castFragment(Class<T> fragmentClass, @Nullable Object fragm
   private static final String FRAGMENT_TAG = "FirestoreOnStopObserverFragment";
 
   /**
-   * Implementation for non-FragmentActivity Activity's. Unfortunatly, all Fragment related
-   * classes/methods with nonFragmentActivityActivity's are deprecated, implying that almost
+   * Implementation for non-FragmentActivity Activities. Unfortunately, all Fragment related
+   * classes/methods with nonFragmentActivityActivities are deprecated, implying that almost
    * everything in this function is deprecated.
    */
   @SuppressWarnings("deprecation")

firebase-firestore/src/test/java/com/google/firebase/firestore/DocumentChangeTest.java

@@ -24,7 +24,7 @@
 import static com.google.firebase.firestore.testutil.TestUtil.path;
 import static com.google.firebase.firestore.testutil.TestUtil.targetChange;
 import static java.util.Arrays.asList;
-import static junit.framework.Assert.assertEquals;
+import static org.junit.Assert.assertEquals;
 import static org.mockito.Mockito.mock;
 
 import com.google.firebase.database.collection.ImmutableSortedMap;

firebase-firestore/src/test/java/com/google/firebase/firestore/TestUtil.java

@@ -36,7 +36,7 @@
 import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
-import junit.framework.Assert;
+import org.junit.Assert;
 import org.robolectric.Robolectric;
 
 public class TestUtil {

firebase-firestore/src/test/java/com/google/firebase/firestore/core/EventManagerTest.java

@@ -15,8 +15,8 @@
 package com.google.firebase.firestore.core;
 
 import static com.google.firebase.firestore.testutil.TestUtil.path;
-import static junit.framework.Assert.assertEquals;
-import static org.mockito.Matchers.any;
+import static org.junit.Assert.assertEquals;
+import static org.mockito.ArgumentMatchers.any;
 import static org.mockito.Mockito.doAnswer;
 import static org.mockito.Mockito.inOrder;
 import static org.mockito.Mockito.mock;

firebase-firestore/src/test/java/com/google/firebase/firestore/local/LruGarbageCollectorTestCase.java

@@ -124,7 +124,7 @@ private QueryData addNextQuery() {
   }
 
   private DocumentKey nextTestDocumentKey() {
-    return DocumentKey.fromPathString("docs/doc_" + (++previousDocNum));
+    return DocumentKey.fromPathString("docs/doc_" + ++previousDocNum);
   }
 
   private Document nextTestDocument() {

firebase-firestore/src/test/java/com/google/firebase/firestore/local/RemoteDocumentCacheTestCase.java

@@ -106,7 +106,7 @@ public void testReadSeveralDocumentsIncludingMissingDocument() {
     }
     written.put(DocumentKey.fromPathString("foo/nonexistent"), null);
 
-    List<String> keys = new ArrayList(Arrays.asList(paths));
+    List<String> keys = new ArrayList<>(Arrays.asList(paths));
     keys.add("foo/nonexistent");
     Map<DocumentKey, MaybeDocument> read = getAll(keys);
     assertEquals(written, read);

firebase-firestore/src/test/java/com/google/firebase/firestore/local/SQLiteSchemaTest.java

@@ -291,7 +291,7 @@ public void addsSentinelRows() {
               String path = row.getString(0);
               long sequenceNumber = row.getLong(1);
 
-              int docNum = Integer.parseInt(path.split("_")[1]);
+              int docNum = Integer.parseInt(path.split("_", -1)[1]);
               // The even documents were missing sequence numbers, they should now be filled in
               // to have the new sequence number. The odd documents should have their
               // sequence number unchanged, and so be the old value.

firebase-firestore/src/test/java/com/google/firebase/firestore/model/DocumentSetTest.java

@@ -18,10 +18,10 @@
 import static com.google.firebase.firestore.testutil.TestUtil.docSet;
 import static com.google.firebase.firestore.testutil.TestUtil.field;
 import static com.google.firebase.firestore.testutil.TestUtil.map;
-import static junit.framework.Assert.assertFalse;
-import static junit.framework.Assert.assertNull;
 import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertFalse;
 import static org.junit.Assert.assertNotEquals;
+import static org.junit.Assert.assertNull;
 import static org.junit.Assert.assertTrue;
 
 import com.google.firebase.firestore.model.value.FieldValue;
@@ -38,13 +38,10 @@
 public class DocumentSetTest {
 
   private static final Comparator<Document> TEST_COMPARATOR =
-      new Comparator<Document>() {
-        @Override
-        public int compare(Document left, Document right) {
-          FieldValue leftValue = left.getField(field("sort"));
-          FieldValue rightValue = right.getField(field("sort"));
-          return leftValue.compareTo(rightValue);
-        }
+      (left, right) -> {
+        FieldValue leftValue = left.getField(field("sort"));
+        FieldValue rightValue = right.getField(field("sort"));
+        return leftValue.compareTo(rightValue);
       };
 
   private static final Document DOC1 = doc("docs/1", 0, map("sort", 2));

firebase-firestore/src/test/java/com/google/firebase/firestore/model/FieldValueTest.java

@@ -275,7 +275,7 @@ public void testExtractsFields() {
     FieldValue val = wrapObject("foo", map("a", 1, "b", true, "c", "string"));
     assertTrue(val instanceof ObjectValue);
     ObjectValue obj = (ObjectValue) val;
-    assertTrue((obj.get(field("foo"))) instanceof ObjectValue);
+    assertTrue(obj.get(field("foo")) instanceof ObjectValue);
     assertEquals(wrap(1), obj.get(field("foo.a")));
     assertEquals(wrap(true), obj.get(field("foo.b")));
     assertEquals(wrap("string"), obj.get(field("foo.c")));

firebase-firestore/src/test/java/com/google/firebase/firestore/remote/RemoteEventTest.java

@@ -25,11 +25,11 @@
 import static com.google.firebase.firestore.testutil.TestUtil.version;
 import static java.util.Arrays.asList;
 import static java.util.Collections.emptyList;
-import static junit.framework.Assert.fail;
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertFalse;
 import static org.junit.Assert.assertNull;
 import static org.junit.Assert.assertTrue;
+import static org.junit.Assert.fail;
 
 import com.google.firebase.database.collection.ImmutableSortedSet;
 import com.google.firebase.firestore.TestUtil.TestTargetMetadataProvider;

firebase-firestore/src/test/java/com/google/firebase/firestore/util/MapperTest.java

@@ -41,7 +41,7 @@
 @Config(manifest = Config.NONE)
 @SuppressWarnings({"unused", "WeakerAccess", "SpellCheckingInspection"})
 public class MapperTest {
-  private static final double EPSILON = 0.00001f;
+  private static final double EPSILON = 0.0003;
 
   private static class StringBean {
     private String value;