Implement equals and hashCode in StatusOr and other things discussed.

api/src/main/java/io/grpc/NameResolver.java

@@ -94,7 +94,7 @@ public void onError(Status error) {
 
           @Override
           public void onResult(ResolutionResult resolutionResult) {
-            listener.onAddresses(resolutionResult.getAddressesOrError().value(),
+            listener.onAddresses(resolutionResult.getAddressesOrError().getValue(),
                 resolutionResult.getAttributes());
           }
       });
@@ -219,14 +219,14 @@ public abstract static class Listener2 implements Listener {
     @Deprecated
     @InlineMe(
         replacement = "this.onResult2(ResolutionResult.newBuilder().setAddressesOrError("
-            + "StatusOr.fromValue(servers)).setAttributes(attributes).build())",
+            + "StatusOr.of(servers)).setAttributes(attributes).build())",
         imports = {"io.grpc.NameResolver.ResolutionResult", "io.grpc.StatusOr"})
     public final void onAddresses(
         List<EquivalentAddressGroup> servers, @ResolutionResultAttr Attributes attributes) {
       // TODO(jihuncho) need to promote Listener2 if we want to use ConfigOrError
       onResult2(
           ResolutionResult.newBuilder().setAddressesOrError(
-              StatusOr.fromValue(servers)).setAttributes(attributes).build());
+              StatusOr.of(servers)).setAttributes(attributes).build());
     }
 
     /**
@@ -605,7 +605,7 @@ public static final class ResolutionResult {
         List<EquivalentAddressGroup> addresses,
         @ResolutionResultAttr Attributes attributes,
         ConfigOrError serviceConfig) {
-      this.addressesOrError = StatusOr.fromValue(addresses);
+      this.addressesOrError = StatusOr.of(addresses);
       this.attributes = checkNotNull(attributes, "attributes");
       this.serviceConfig = serviceConfig;
     }
@@ -639,7 +639,7 @@ public Builder toBuilder() {
      */
     @Deprecated
     public List<EquivalentAddressGroup> getAddresses() {
-      return addressesOrError.value();
+      return addressesOrError.getValue();
     }
 
     /**
@@ -711,7 +711,7 @@ public int hashCode() {
     @ExperimentalApi("https://github.com/grpc/grpc-java/issues/1770")
     public static final class Builder {
       private StatusOr<List<EquivalentAddressGroup>> addresses =
-          StatusOr.fromValue(Collections.emptyList());
+          StatusOr.of(Collections.emptyList());
       private Attributes attributes = Attributes.EMPTY;
       @Nullable
       private ConfigOrError serviceConfig;
@@ -727,7 +727,7 @@ public static final class Builder {
        */
       @Deprecated
       public Builder setAddresses(List<EquivalentAddressGroup> addresses) {
-        this.addresses = StatusOr.fromValue(addresses);
+        this.addresses = StatusOr.of(addresses);
         return this;
       }
 

api/src/main/java/io/grpc/StatusOr.java

@@ -19,6 +19,8 @@
 import static com.google.common.base.Preconditions.checkArgument;
 import static com.google.common.base.Preconditions.checkNotNull;
 
+import com.google.common.base.Objects;
+
 /** Either a Status or a value. */
 public class StatusOr<T> {
   private StatusOr(Status status, T value) {
@@ -27,7 +29,7 @@ private StatusOr(Status status, T value) {
   }
 
   /** Construct from a value. */
-  public static <T> StatusOr<T> fromValue(T value) {
+  public static <T> StatusOr<T> of(T value) {
     StatusOr<T> result = new StatusOr<T>(null, checkNotNull(value, "value"));
     return result;
   }
@@ -45,15 +47,36 @@ public boolean hasValue() {
   }
 
   /** Returns the value if set, or null in case of a non-OK status. */
-  public T value() {
+  public T getValue() {
     return value;
   }
 
   /** Returns the status. If there is a value, returns OK. */
-  public Status status() {
+  public Status getStatus() {
     return value != null ? Status.OK : status;
   }
 
+  @Override
+  @SuppressWarnings("ReferenceEquality")
+  public boolean equals(Object other) {
+    if (!(other instanceof StatusOr)) {
+      return false;
+    }
+    StatusOr<T> otherStatus = (StatusOr) other;
+    if (hasValue() != otherStatus.hasValue()) {
+      return false;
+    }
+    if (hasValue()) {
+      return Objects.equal(value, otherStatus.value);
+    }
+    return status == otherStatus.status;
+  }
+
+  @Override
+  public int hashCode() {
+    return Objects.hashCode(status, value);
+  }
+
   private final Status status;
   private final T value;
 }

core/src/main/java/io/grpc/internal/DnsNameResolver.java

@@ -315,7 +315,7 @@ public void run() {
             logger.finer("Using proxy address " + proxiedAddr);
           }
           resolutionResultBuilder.setAddressesOrError(
-              StatusOr.fromValue(Collections.singletonList(proxiedAddr)));
+              StatusOr.of(Collections.singletonList(proxiedAddr)));
         } else {
           result = doResolve(false);
           if (result.error != null) {
@@ -327,7 +327,7 @@ public void run() {
             return;
           }
           if (result.addresses != null) {
-            resolutionResultBuilder.setAddressesOrError(StatusOr.fromValue(result.addresses));
+            resolutionResultBuilder.setAddressesOrError(StatusOr.of(result.addresses));
           }
           if (result.config != null) {
             resolutionResultBuilder.setServiceConfig(result.config);

core/src/main/java/io/grpc/internal/ManagedChannelImpl.java

@@ -1705,12 +1705,12 @@ public Status onResult2(final ResolutionResult resolutionResult) {
 
         if (lastResolutionState != ResolutionState.SUCCESS) {
           channelLogger.log(ChannelLogLevel.INFO, "Address resolved: {0}",
-              serversOrError.value());
+              serversOrError.getValue());
           lastResolutionState = ResolutionState.SUCCESS;
         }
       } else if (serversOrError != null && !serversOrError.hasValue()) {
-        handleErrorInSyncContext(serversOrError.status());
-        return serversOrError.status();
+        handleErrorInSyncContext(serversOrError.getStatus());
+        return serversOrError.getStatus();
       }
       ConfigOrError configOrError = resolutionResult.getServiceConfig();
       InternalConfigSelector resolvedConfigSelector =
@@ -1815,7 +1815,7 @@ public Status onResult2(final ResolutionResult resolutionResult) {
 
         ResolvedAddresses.Builder resolvedAddresses = ResolvedAddresses.newBuilder();
         if (serversOrError != null && serversOrError.hasValue()) {
-          resolvedAddresses.setAddresses(serversOrError.value());
+          resolvedAddresses.setAddresses(serversOrError.getValue());
         } else {
           resolvedAddresses.setAddresses(new ArrayList<>());
         }

core/src/main/java/io/grpc/internal/ManagedChannelImplBuilder.java

@@ -881,7 +881,7 @@ public void start(Listener2 listener) {
           listener.onResult2(
               ResolutionResult.newBuilder()
                   .setAddressesOrError(
-                      StatusOr.fromValue(
+                      StatusOr.of(
                           Collections.singletonList(new EquivalentAddressGroup(address))))
                   .setAttributes(Attributes.EMPTY)
                   .build());

core/src/test/java/io/grpc/internal/DnsNameResolverTest.java

@@ -568,7 +568,7 @@ public List<InetAddress> resolveAddress(String host) throws Exception {
     ArgumentCaptor<ResolutionResult> ac = ArgumentCaptor.forClass(ResolutionResult.class);
     verify(mockListener).onResult2(ac.capture());
     verifyNoMoreInteractions(mockListener);
-    assertThat(ac.getValue().getAddressesOrError().value()).isEmpty();
+    assertThat(ac.getValue().getAddressesOrError().getValue()).isEmpty();
     assertThat(ac.getValue().getServiceConfig()).isNull();
     verify(mockResourceResolver, never()).resolveSrv(anyString());
 
@@ -602,7 +602,7 @@ public List<InetAddress> resolveAddress(String host) throws Exception {
     ArgumentCaptor<ResolutionResult> ac = ArgumentCaptor.forClass(ResolutionResult.class);
     verify(mockListener).onResult2(ac.capture());
     verifyNoMoreInteractions(mockListener);
-    assertThat(ac.getValue().getAddressesOrError().value()).isEmpty();
+    assertThat(ac.getValue().getAddressesOrError().getValue()).isEmpty();
     assertThat(ac.getValue().getServiceConfig()).isNull();
     verify(mockResourceResolver, never()).resolveSrv(anyString());
 
@@ -630,7 +630,7 @@ public void resolve_nullResourceResolver() throws Exception {
     ResolutionResult result = resultCaptor.getValue();
     InetSocketAddress resolvedBackendAddr =
         (InetSocketAddress) Iterables.getOnlyElement(
-            Iterables.getOnlyElement(result.getAddressesOrError().value()).getAddresses());
+            Iterables.getOnlyElement(result.getAddressesOrError().getValue()).getAddresses());
     assertThat(resolvedBackendAddr.getAddress()).isEqualTo(backendAddr);
     verify(mockAddressResolver).resolveAddress(name);
     assertThat(result.getServiceConfig()).isNull();
@@ -655,7 +655,7 @@ public void resolve_nullResourceResolver_addressFailure() throws Exception {
     resolver.start(mockListener);
     assertEquals(1, fakeExecutor.runDueTasks());
     verify(mockListener).onResult2(resultCaptor.capture());
-    Status errorStatus = resultCaptor.getValue().getAddressesOrError().status();
+    Status errorStatus = resultCaptor.getValue().getAddressesOrError().getStatus();
     assertThat(errorStatus.getCode()).isEqualTo(Code.UNAVAILABLE);
     assertThat(errorStatus.getCause()).hasMessageThat().contains("no addr");
 
@@ -703,7 +703,7 @@ public ConfigOrError parseServiceConfig(Map<String, ?> rawServiceConfig) {
     ResolutionResult result = resultCaptor.getValue();
     InetSocketAddress resolvedBackendAddr =
         (InetSocketAddress) Iterables.getOnlyElement(
-            Iterables.getOnlyElement(result.getAddressesOrError().value()).getAddresses());
+            Iterables.getOnlyElement(result.getAddressesOrError().getValue()).getAddresses());
     assertThat(resolvedBackendAddr.getAddress()).isEqualTo(backendAddr);
     assertThat(result.getServiceConfig().getConfig()).isNotNull();
     verify(mockAddressResolver).resolveAddress(name);
@@ -730,7 +730,7 @@ public void resolve_addressFailure_neverLookUpServiceConfig() throws Exception {
     resolver.start(mockListener);
     assertEquals(1, fakeExecutor.runDueTasks());
     verify(mockListener).onResult2(resultCaptor.capture());
-    Status errorStatus = resultCaptor.getValue().getAddressesOrError().status();
+    Status errorStatus = resultCaptor.getValue().getAddressesOrError().getStatus();
     assertThat(errorStatus.getCode()).isEqualTo(Code.UNAVAILABLE);
     assertThat(errorStatus.getCause()).hasMessageThat().contains("no addr");
     verify(mockResourceResolver, never()).resolveTxt(anyString());
@@ -762,7 +762,7 @@ public void resolve_serviceConfigLookupFails_nullServiceConfig() throws Exceptio
     ResolutionResult result = resultCaptor.getValue();
     InetSocketAddress resolvedBackendAddr =
         (InetSocketAddress) Iterables.getOnlyElement(
-            Iterables.getOnlyElement(result.getAddressesOrError().value()).getAddresses());
+            Iterables.getOnlyElement(result.getAddressesOrError().getValue()).getAddresses());
     assertThat(resolvedBackendAddr.getAddress()).isEqualTo(backendAddr);
     verify(mockAddressResolver).resolveAddress(name);
     assertThat(result.getServiceConfig()).isNull();
@@ -794,7 +794,7 @@ public void resolve_serviceConfigMalformed_serviceConfigError() throws Exception
     ResolutionResult result = resultCaptor.getValue();
     InetSocketAddress resolvedBackendAddr =
         (InetSocketAddress) Iterables.getOnlyElement(
-            Iterables.getOnlyElement(result.getAddressesOrError().value()).getAddresses());
+            Iterables.getOnlyElement(result.getAddressesOrError().getValue()).getAddresses());
     assertThat(resolvedBackendAddr.getAddress()).isEqualTo(backendAddr);
     verify(mockAddressResolver).resolveAddress(name);
     assertThat(result.getServiceConfig()).isNotNull();
@@ -859,7 +859,7 @@ public HttpConnectProxiedSocketAddress proxyFor(SocketAddress targetAddress) {
     assertEquals(1, fakeExecutor.runDueTasks());
 
     verify(mockListener).onResult2(resultCaptor.capture());
-    List<EquivalentAddressGroup> result = resultCaptor.getValue().getAddressesOrError().value();
+    List<EquivalentAddressGroup> result = resultCaptor.getValue().getAddressesOrError().getValue();
     assertThat(result).hasSize(1);
     EquivalentAddressGroup eag = result.get(0);
     assertThat(eag.getAddresses()).hasSize(1);
@@ -1299,9 +1299,9 @@ private List<InetAddress> createAddressList(int n) throws UnknownHostException {
 
   private static void assertAnswerMatches(
       List<InetAddress> addrs, int port, ResolutionResult resolutionResult) {
-    assertThat(resolutionResult.getAddressesOrError().value()).hasSize(addrs.size());
+    assertThat(resolutionResult.getAddressesOrError().getValue()).hasSize(addrs.size());
     for (int i = 0; i < addrs.size(); i++) {
-      EquivalentAddressGroup addrGroup = resolutionResult.getAddressesOrError().value().get(i);
+      EquivalentAddressGroup addrGroup = resolutionResult.getAddressesOrError().getValue().get(i);
       InetSocketAddress socketAddr =
           (InetSocketAddress) Iterables.getOnlyElement(addrGroup.getAddresses());
       assertEquals("Addr " + i, port, socketAddr.getPort());

core/src/test/java/io/grpc/internal/ManagedChannelImplIdlenessTest.java

@@ -616,7 +616,7 @@ private void deliverResolutionResult() {
     // the NameResolver.
     ResolutionResult resolutionResult =
         ResolutionResult.newBuilder()
-            .setAddressesOrError(StatusOr.fromValue(servers))
+            .setAddressesOrError(StatusOr.of(servers))
             .setAttributes(Attributes.EMPTY)
             .build();
     nameResolverListenerCaptor.getValue().onResult(resolutionResult);

grpclb/src/test/java/io/grpc/grpclb/GrpclbNameResolverTest.java

@@ -153,7 +153,7 @@ public List<SrvRecord> resolveSrv(String host) throws Exception {
 
     verify(mockListener).onResult2(resultCaptor.capture());
     ResolutionResult result = resultCaptor.getValue();
-    assertThat(result.getAddressesOrError().value()).isEmpty();
+    assertThat(result.getAddressesOrError().getValue()).isEmpty();
     assertThat(result.getAttributes()).isEqualTo(Attributes.EMPTY);
     assertThat(result.getServiceConfig()).isNull();
   }
@@ -195,7 +195,7 @@ public ConfigOrError answer(InvocationOnMock invocation) {
     ResolutionResult result = resultCaptor.getValue();
     InetSocketAddress resolvedBackendAddr =
         (InetSocketAddress) Iterables.getOnlyElement(
-            Iterables.getOnlyElement(result.getAddressesOrError().value()).getAddresses());
+            Iterables.getOnlyElement(result.getAddressesOrError().getValue()).getAddresses());
     assertThat(resolvedBackendAddr.getAddress()).isEqualTo(backendAddr);
     EquivalentAddressGroup resolvedBalancerAddr =
         Iterables.getOnlyElement(result.getAttributes().get(GrpclbConstants.ATTR_LB_ADDRS));
@@ -226,7 +226,7 @@ public void resolve_nullResourceResolver() throws Exception {
     assertThat(fakeClock.runDueTasks()).isEqualTo(1);
     verify(mockListener).onResult2(resultCaptor.capture());
     ResolutionResult result = resultCaptor.getValue();
-    assertThat(result.getAddressesOrError().value())
+    assertThat(result.getAddressesOrError().getValue())
         .containsExactly(
             new EquivalentAddressGroup(new InetSocketAddress(backendAddr, DEFAULT_PORT)));
     assertThat(result.getAttributes()).isEqualTo(Attributes.EMPTY);
@@ -245,7 +245,7 @@ public void resolve_nullResourceResolver_addressFailure() throws Exception {
     resolver.start(mockListener);
     assertThat(fakeClock.runDueTasks()).isEqualTo(1);
     verify(mockListener).onResult2(resultCaptor.capture());
-    Status errorStatus = resultCaptor.getValue().getAddressesOrError().status();
+    Status errorStatus = resultCaptor.getValue().getAddressesOrError().getStatus();
     assertThat(errorStatus.getCode()).isEqualTo(Code.UNAVAILABLE);
     assertThat(errorStatus.getCause()).hasMessageThat().contains("no addr");
   }
@@ -273,7 +273,7 @@ public void resolve_addressFailure_stillLookUpBalancersAndServiceConfig() throws
     assertThat(fakeClock.runDueTasks()).isEqualTo(1);
     verify(mockListener).onResult2(resultCaptor.capture());
     ResolutionResult result = resultCaptor.getValue();
-    assertThat(result.getAddressesOrError().value()).isEmpty();
+    assertThat(result.getAddressesOrError().getValue()).isEmpty();
     EquivalentAddressGroup resolvedBalancerAddr =
         Iterables.getOnlyElement(result.getAttributes().get(GrpclbConstants.ATTR_LB_ADDRS));
     assertThat(resolvedBalancerAddr.getAttributes().get(GrpclbConstants.ATTR_LB_ADDR_AUTHORITY))
@@ -310,7 +310,7 @@ public void resolveAll_balancerLookupFails_stillLookUpServiceConfig() throws Exc
 
     InetSocketAddress resolvedBackendAddr =
         (InetSocketAddress) Iterables.getOnlyElement(
-            Iterables.getOnlyElement(result.getAddressesOrError().value()).getAddresses());
+            Iterables.getOnlyElement(result.getAddressesOrError().getValue()).getAddresses());
     assertThat(resolvedBackendAddr.getAddress()).isEqualTo(backendAddr);
     assertThat(result.getAttributes().get(GrpclbConstants.ATTR_LB_ADDRS)).isNull();
     verify(mockAddressResolver).resolveAddress(hostName);
@@ -335,7 +335,7 @@ public void resolve_addressAndBalancersLookupFail_neverLookupServiceConfig() thr
     resolver.start(mockListener);
     assertThat(fakeClock.runDueTasks()).isEqualTo(1);
     verify(mockListener).onResult2(resultCaptor.capture());
-    Status errorStatus = resultCaptor.getValue().getAddressesOrError().status();
+    Status errorStatus = resultCaptor.getValue().getAddressesOrError().getStatus();
     assertThat(errorStatus.getCode()).isEqualTo(Code.UNAVAILABLE);
     verify(mockAddressResolver).resolveAddress(hostName);
     verify(mockResourceResolver, never()).resolveTxt("_grpc_config." + hostName);

netty/src/main/java/io/grpc/netty/UdsNameResolver.java

@@ -60,7 +60,7 @@ private void resolve() {
     ResolutionResult.Builder resolutionResultBuilder = ResolutionResult.newBuilder();
     List<EquivalentAddressGroup> servers = new ArrayList<>(1);
     servers.add(new EquivalentAddressGroup(new DomainSocketAddress(authority)));
-    resolutionResultBuilder.setAddressesOrError(StatusOr.fromValue(servers));
+    resolutionResultBuilder.setAddressesOrError(StatusOr.of(servers));
     syncContext.execute(() ->
         listener.onResult2(resolutionResultBuilder.build()));
   }

netty/src/test/java/io/grpc/netty/UdsNameResolverProviderTest.java

@@ -79,7 +79,7 @@ public void testUnixRelativePath() {
     udsNameResolver.start(mockListener);
     verify(mockListener).onResult2(resultCaptor.capture());
     NameResolver.ResolutionResult result = resultCaptor.getValue();
-    List<EquivalentAddressGroup> list = result.getAddressesOrError().value();
+    List<EquivalentAddressGroup> list = result.getAddressesOrError().getValue();
     assertThat(list).isNotNull();
     assertThat(list).hasSize(1);
     EquivalentAddressGroup eag = list.get(0);
@@ -99,7 +99,7 @@ public void testUnixAbsolutePath() {
     udsNameResolver.start(mockListener);
     verify(mockListener).onResult2(resultCaptor.capture());
     NameResolver.ResolutionResult result = resultCaptor.getValue();
-    List<EquivalentAddressGroup> list = result.getAddressesOrError().value();
+    List<EquivalentAddressGroup> list = result.getAddressesOrError().getValue();
     assertThat(list).isNotNull();
     assertThat(list).hasSize(1);
     EquivalentAddressGroup eag = list.get(0);
@@ -119,7 +119,7 @@ public void testUnixAbsoluteAlternatePath() {
     udsNameResolver.start(mockListener);
     verify(mockListener).onResult2(resultCaptor.capture());
     NameResolver.ResolutionResult result = resultCaptor.getValue();
-    List<EquivalentAddressGroup> list = result.getAddressesOrError().value();
+    List<EquivalentAddressGroup> list = result.getAddressesOrError().getValue();
     assertThat(list).isNotNull();
     assertThat(list).hasSize(1);
     EquivalentAddressGroup eag = list.get(0);

netty/src/test/java/io/grpc/netty/UdsNameResolverTest.java

@@ -75,7 +75,7 @@ public void testValidTargetPath() {
     udsNameResolver.start(mockListener);
     verify(mockListener).onResult2(resultCaptor.capture());
     NameResolver.ResolutionResult result = resultCaptor.getValue();
-    List<EquivalentAddressGroup> list = result.getAddressesOrError().value();
+    List<EquivalentAddressGroup> list = result.getAddressesOrError().getValue();
     assertThat(list).isNotNull();
     assertThat(list).hasSize(1);
     EquivalentAddressGroup eag = list.get(0);