Use the Java 7 diamond operator everywhere. (#643)

CHANGELOG.md

@@ -13,6 +13,7 @@ When updating the changelog, remember to be very clear about what behavior has c
 and what APIs have changed, if applicable.
 
 ## [Unreleased]
+- Use the Java 7 diamond operator everywhere.
 
 ## [29.19.4] - 2021-06-23
 - Do not apply Idea and Eclipse plugins.

d2-benchmark/src/jmh/java/com/linkedin/d2/util/hashing/ConsistentHashRingBenchmark.java

@@ -208,7 +208,7 @@ public URI measureBoundedLoad_firstFull_MPCHash_100Hosts_21Probes(BoundedLoad_MP
 
   @State(Scope.Benchmark)
   public static class ConsistentHashRing_10Hosts_100PointsPerHost_State {
-    Ring<URI> _ring = new ConsistentHashRing<URI>(buildPointsMap(10, 100));
+    Ring<URI> _ring = new ConsistentHashRing<>(buildPointsMap(10, 100));
     Random _random = new Random();
   }
 
@@ -247,7 +247,7 @@ public URI measureBoundedLoad_firstFull_ConsistentHashRing_10Hosts_100PointsPerH
 
   @State(Scope.Benchmark)
   public static class ConsistentHashRing_100Hosts_100PointsPerHost_State {
-    Ring<URI> _ring = new ConsistentHashRing<URI>(buildPointsMap(100, 100));
+    Ring<URI> _ring = new ConsistentHashRing<>(buildPointsMap(100, 100));
     Random _random = new Random();
   }
 

d2-contrib/src/main/java/com/linkedin/d2/contrib/RouteLookupClient.java

@@ -103,7 +103,7 @@ public Future<RestResponse> restRequest(RestRequest request, String routeKey)
   public Future<RestResponse> restRequest(final RestRequest request, final RequestContext requestContext,
                                           String routekey)
   {
-    final FutureCallback<String> futureCallback = new FutureCallback<String>();
+    final FutureCallback<String> futureCallback = new FutureCallback<>();
     String originalServiceName = LoadBalancerUtil.getServiceNameFromUri(request.getURI());
     String resultServiceName;
     _routeLookup.run(originalServiceName, _routingGroup, routekey, futureCallback);

d2-contrib/src/test/java/com/linkedin/d2/contrib/TestRouteLookupClient.java

@@ -21,7 +21,6 @@
 package com.linkedin.d2.contrib;
 
 import com.linkedin.common.callback.FutureCallback;
-import com.linkedin.common.util.None;
 import com.linkedin.d2.balancer.D2Client;
 import com.linkedin.d2.balancer.D2ClientBuilder;
 import com.linkedin.r2.message.rest.RestRequest;
@@ -49,14 +48,14 @@ public void testSimpleRouteLookup() throws ExecutionException, InterruptedExcept
   {
     RouteLookup routeLookup = new SimpleTestRouteLookup();
 
-    FutureCallback<String> futureCallback = new FutureCallback<String>();
+    FutureCallback<String> futureCallback = new FutureCallback<>();
     String serviceName = "BarBar";
     routeLookup.run(serviceName, null, "1",futureCallback);
 
     String resultString = futureCallback.get();
     Assert.assertEquals(resultString, serviceName + "1" + "Foo");
 
-    futureCallback = new FutureCallback<String>();
+    futureCallback = new FutureCallback<>();
     routeLookup.run(serviceName, "blah", "2",futureCallback);
     resultString = futureCallback.get();
     Assert.assertEquals(resultString, serviceName + "blah" + "2" + "Foo");
@@ -68,7 +67,7 @@ public void testRouteLookupClientFuture() throws ExecutionException, Interrupted
     RouteLookup routeLookup = new SimpleTestRouteLookup();
 
     final D2Client d2Client = new D2ClientBuilder().setZkHosts("localhost:2121").build();
-    d2Client.start(new FutureCallback<None>());
+    d2Client.start(new FutureCallback<>());
     RouteLookupClient routeLookupClient = new RouteLookupClient(d2Client, routeLookup, "WestCoast");
     RestRequest dummyRestRequest = new RestRequestBuilder(URI.create("d2://simple_uri")).build();
     Future<RestResponse> future = routeLookupClient.restRequest(dummyRestRequest, "5436");
@@ -97,10 +96,10 @@ public void testRouteLookupClientCallback()
     RouteLookup routeLookup = new SimpleTestRouteLookup();
 
     final D2Client d2Client = new D2ClientBuilder().setZkHosts("localhost:2121").build();
-    d2Client.start(new FutureCallback<None>());
+    d2Client.start(new FutureCallback<>());
     RouteLookupClient routeLookupClient = new RouteLookupClient(d2Client, routeLookup, "WestCoast");
     RestRequest dummyRestRequest = new RestRequestBuilder(URI.create("d2://simple_uri")).build();
-    FutureCallback<RestResponse> futureCallback = new FutureCallback<RestResponse>();
+    FutureCallback<RestResponse> futureCallback = new FutureCallback<>();
     routeLookupClient.restRequest(dummyRestRequest,futureCallback, "5555");
 
     try
@@ -124,7 +123,7 @@ public void testBadRequest()
     RouteLookup routeLookup = new SimpleTestRouteLookup();
 
     final D2Client d2Client = new D2ClientBuilder().setZkHosts("localhost:2121").build();
-    d2Client.start(new FutureCallback<None>());
+    d2Client.start(new FutureCallback<>());
     RouteLookupClient routeLookupClient = new RouteLookupClient(d2Client, routeLookup, "WestCoast");
     RestRequest dummyRestRequest = new RestRequestBuilder(URI.create("http://simple_uri")).build();
     try

d2-int-test/src/test/java/com/linkedin/d2/D2BaseTest.java

@@ -265,7 +265,7 @@ public Map<String,AtomicInteger> sendRequests(int num,
 
   public  Map<String, List<String>> generateClusterData(String[] clusters, int addOn)
   {
-    Map<String, List<String>> clustersData = new HashMap<String, List<String>> ();
+    Map<String, List<String>> clustersData = new HashMap<>();
 
     for (int i=0; i < clusters.length; i++)
     {
@@ -276,8 +276,8 @@ public  Map<String, List<String>> generateClusterData(String[] clusters, int add
 
   public Map<String, Object> generatePartitionProperties(String regex, int keyRangeStart, int partitionCount, int partitionSize, String type)
   {
-    final Map<String, Object> partitionProperties = new HashMap<String, Object>();
-    Map<String, Object> map = new HashMap<String, Object>();
+    final Map<String, Object> partitionProperties = new HashMap<>();
+    Map<String, Object> map = new HashMap<>();
     map.put("partitionKeyRegex", regex);
     map.put("keyRangeStart", String.valueOf(keyRangeStart));
     map.put("partitionCount", String.valueOf(partitionCount));
@@ -290,7 +290,7 @@ public Map<String, Object> generatePartitionProperties(String regex, int keyRang
 
   protected <T> Map<LoadBalancerEchoServer,T> createLatencyDataHash(List<LoadBalancerEchoServer> servers, T[] latency)
   {
-    Map<LoadBalancerEchoServer,T> hash = new HashMap<LoadBalancerEchoServer,T>();
+    Map<LoadBalancerEchoServer,T> hash = new HashMap<>();
     int count = 0;
     for (LoadBalancerEchoServer server: servers)
     {
@@ -308,13 +308,13 @@ protected <T> Map<LoadBalancerEchoServer,T> createLatencyDataHash(List<LoadBalan
 
   protected static Map<LoadBalancerEchoServer,Map<Integer, Double>> createServerWeightDataMap(List<LoadBalancerEchoServer> servers, int partitionId, Double[] weight)
   {
-    Map<LoadBalancerEchoServer,Map<Integer, Double>> hash = new HashMap<LoadBalancerEchoServer,Map<Integer, Double>>();
+    Map<LoadBalancerEchoServer,Map<Integer, Double>> hash = new HashMap<>();
     int count = 0;
     for (LoadBalancerEchoServer server: servers)
     {
       if (count < weight.length)
       {
-        Map<Integer, Double> partitionWeight = new HashMap<Integer, Double> ();
+        Map<Integer, Double> partitionWeight = new HashMap<>();
         partitionWeight.put(Integer.valueOf(partitionId), weight[count]);
         hash.put(server, partitionWeight);
         count++;
@@ -344,7 +344,7 @@ protected void assertServersWeighSetup(Map<LoadBalancerEchoServer,Map<Integer, D
 
   protected Map<Integer,AtomicInteger> generateHostResponseCountMap(Map<String,String> responses)
   {
-    Map<Integer,AtomicInteger> res = new HashMap<Integer,AtomicInteger>();
+    Map<Integer,AtomicInteger> res = new HashMap<>();
 
     res.put(Integer.valueOf(ECHO_SERVER_PORT1_1), new AtomicInteger(0));
     res.put(Integer.valueOf(ECHO_SERVER_PORT1_2), new AtomicInteger(0));

d2-int-test/src/test/java/com/linkedin/d2/discovery/TestD2ConfigWithSingleZKFailover.java

@@ -66,10 +66,10 @@ public void setup() throws IOException, Exception
     _zkPort = _zkServer.getPort();
     _zkHosts = ZK_HOST+":" + _zkPort;
     _zkUriString = "zk://"+_zkHosts;
-    
+
     // Register clusters/services  (two services per cluster)
     LoadBalancerClientCli.runDiscovery(_zkHosts, "/d2", D2_CONFIG_DATA);
-    
+
     // Get LoadBalancer Client
     _cli = new LoadBalancerClientCli(_zkHosts, "/d2");
 
@@ -235,7 +235,7 @@ public void testEchoServerMarkDownUp() throws IOException, InterruptedException,
      // Echo Server mark up
      _echoServers.get(1).markUp();
      _echoServers.get(2).markUp();
-     
+
      msg = generateMessage(_zkUriString);
      expectedResponses =  getExpectedResponses(0, msg);
 
@@ -297,7 +297,7 @@ private String getExpectedResponse(int partitionId, String msg, String postfix)
 
    private void startAllEchoServers() throws Exception
    {
-     _echoServers = new ArrayList<LoadBalancerEchoServer>();
+     _echoServers = new ArrayList<>();
      _echoServers.add(startEchoServer(ZK_HOST, _zkPort, ECHO_SERVER_HOST, ECHO_SERVER_PORT1, "cluster-1", "service-1_1", "service-1_2", "service-1_3" ));
      _echoServers.add(startEchoServer(ZK_HOST, _zkPort, ECHO_SERVER_HOST, ECHO_SERVER_PORT2, "cluster-1", "service-1_1", "service-1_2", "service-1_3" ));
      _echoServers.add(startEchoServer(ZK_HOST, _zkPort, ECHO_SERVER_HOST, ECHO_SERVER_PORT3, "cluster-2", "service-2_1", "service-2_2", "service-2_3" ));

d2-int-test/src/test/java/com/linkedin/d2/discovery/TestPartitionsWithZKQuorum.java

@@ -84,7 +84,7 @@ public void testRegisterUnregisterDefaultPartitionEchoServers() throws IOExcepti
                                                 InterruptedException,
                                                 Exception
   {
-    _echoServers = new ArrayList<LoadBalancerEchoServer>();
+    _echoServers = new ArrayList<>();
     setup();
     assertEquals(LoadBalancerClientCli.runDiscovery(_quorum.getHosts(), "/d2", D2_CONFIG_DEFAULT_PARTITION_DATA), 0);
     _cli = new LoadBalancerClientCli(_quorum.getHosts(), "/d2");
@@ -109,13 +109,13 @@ public void testRegisterUnregisterCustomPartitionEchoServers() throws IOExceptio
                                                 InterruptedException,
                                                 Exception
   {
-    _echoServers = new ArrayList<LoadBalancerEchoServer>();
+    _echoServers = new ArrayList<>();
     setup();
     assertEquals(LoadBalancerClientCli.runDiscovery(_quorum.getHosts(), "/d2", D2_CONFIG_CUSTOM_PARTITION_DATA), 0);
     _cli = new LoadBalancerClientCli(_quorum.getHosts(), "/d2");
     _client = _cli.createZKFSTogglingLBClient(_quorum.getHosts(), "/d2", null);
     // Echo servers startup
-    Map<Integer, Double> partitionWeight = new HashMap<Integer, Double>();
+    Map<Integer, Double> partitionWeight = new HashMap<>();
     partitionWeight.put(Integer.valueOf(1), Double.valueOf(1.0d));
     startCustomPartitionEchoServers(partitionWeight);
     assertAllEchoServersRegistered(_cli.getZKClient(), _zkUriString, _echoServers);
@@ -135,13 +135,13 @@ public void testRegisterUnregisterAllEchoServers() throws IOException,
                                                 InterruptedException,
                                                 Exception
   {
-    _echoServers = new ArrayList<LoadBalancerEchoServer>();
+    _echoServers = new ArrayList<>();
     setup();
     assertEquals(LoadBalancerClientCli.runDiscovery(_quorum.getHosts(), "/d2", D2_CONFIG_DATA), 0);
     _cli = new LoadBalancerClientCli(_quorum.getHosts(), "/d2");
     _client = _cli.createZKFSTogglingLBClient(_quorum.getHosts(), "/d2", null);
     // Echo servers startup
-    Map<Integer, Double> partitionWeight = new HashMap<Integer, Double>();
+    Map<Integer, Double> partitionWeight = new HashMap<>();
     partitionWeight.put(Integer.valueOf(1), Double.valueOf(1.0d));
     startAllEchoServers(partitionWeight);
     assertAllEchoServersRegistered(_cli.getZKClient(), _zkUriString, _echoServers);

d2-int-test/src/test/java/com/linkedin/d2/loadbalancer/TestD2ZKQuorumFailover.java

@@ -272,8 +272,8 @@ private void assertQuorumProcessAllRequests(String clustersData) throws Exceptio
 
   private void startAllEchoServers() throws Exception
   {
-    _echoServers = new ArrayList<LoadBalancerEchoServer>();
-    Map<Integer, Double> partitionWeight = new HashMap<Integer, Double>();
+    _echoServers = new ArrayList<>();
+    Map<Integer, Double> partitionWeight = new HashMap<>();
     partitionWeight.put(Integer.valueOf(1), Double.valueOf(1.0d));
     _echoServers.add(startEchoServer(getHost(_zkHosts[0]), getPort(_zkHosts[0]), ECHO_SERVER_HOST, ECHO_SERVER_PORT1_1, "cluster-1", "service-1_1", "service-1_2", "service-1_3" ));
     _echoServers.add(startEchoServer(getHost(_zkHosts[0]), getPort(_zkHosts[0]), ECHO_SERVER_HOST, ECHO_SERVER_PORT1_2, "cluster-1", "service-1_1", "service-1_2", "service-1_3" ));

d2-int-test/src/test/java/com/linkedin/d2/quorum/ZKQuorum.java

@@ -16,8 +16,6 @@
 
 package com.linkedin.d2.quorum;
 
-import java.io.IOException;
-import java.net.InetSocketAddress;
 import java.util.Collections;
 import java.util.HashMap;
 import java.util.Iterator;
@@ -51,10 +49,10 @@ public class ZKQuorum
    * @param n - number of peers in the ensemble ( for test stability, set peer number in a quorum to 7+ (7, 9 or 11) )
    */
 
-  public ZKQuorum(int ttlPeersCount) throws IOException, Exception
+  public ZKQuorum(int ttlPeersCount) throws Exception
   {
-    _peers = new HashMap<Integer, ZKPeer>();
-    _peersView = new HashMap<Long, QuorumServer>();
+    _peers = new HashMap<>();
+    _peersView = new HashMap<>();
     _peerCount = ttlPeersCount;
     _hosts = "";
 
@@ -225,7 +223,7 @@ private boolean isExists(int id)
     return false;
   }
 
-  public void restart(int id) throws IOException, Exception
+  public void restart(int id) throws Exception
   {
     _log.info("Restarting peer #" + getQuorumPeerPortsInfo(id));
     _peers.get(id).shutdown(false);
@@ -248,7 +246,7 @@ public void restartPeersInTerminatedState() throws Exception
     waitForAllPeersUp();
   }
 
-  public void startAll() throws IOException, Exception
+  public void startAll() throws Exception
   {
     for (int id=1; id <= _peerCount; id++)
     {

d2/src/main/java/com/linkedin/d2/backuprequests/LatencyMetric.java

@@ -53,10 +53,10 @@ public class LatencyMetric {
    * - read happens on previously put aside current, once read is completed, the histogram is reset
    *   and put back as inactive
    */
-  private AtomicReference<AbstractHistogram> _current = new AtomicReference<AbstractHistogram>(
+  private AtomicReference<AbstractHistogram> _current = new AtomicReference<>(
       new ShortCountsHistogram(LOWEST_DISCERNIBLE_VALUE, HIGHEST_TRACKABLE_VALUE, NUMBER_OF_SIGNIFICANT_VALUE_DIGITS));
 
-  private AtomicReference<AbstractHistogram> _inactive = new AtomicReference<AbstractHistogram>(
+  private AtomicReference<AbstractHistogram> _inactive = new AtomicReference<>(
       new ShortCountsHistogram(LOWEST_DISCERNIBLE_VALUE, HIGHEST_TRACKABLE_VALUE, NUMBER_OF_SIGNIFICANT_VALUE_DIGITS));
 
   /**

d2/src/main/java/com/linkedin/d2/balancer/D2ClientBuilder.java

@@ -540,7 +540,7 @@ public D2ClientBuilder setDeterministicSubsettingMetadataProvider(DeterministicS
 
   private Map<String, TransportClientFactory> createDefaultTransportClientFactories()
   {
-    final Map<String, TransportClientFactory> clientFactories = new HashMap<String, TransportClientFactory>();
+    final Map<String, TransportClientFactory> clientFactories = new HashMap<>();
     TransportClientFactory transportClientFactory = new HttpClientFactory.Builder().build();
     clientFactories.put("http", transportClientFactory);
     clientFactories.put("https", transportClientFactory);

d2/src/main/java/com/linkedin/d2/balancer/clients/BackupRequestsClient.java

@@ -161,7 +161,7 @@ public Future<RestResponse> restRequest(RestRequest request)
   @Override
   public Future<RestResponse> restRequest(RestRequest request, RequestContext requestContext)
   {
-    final FutureCallback<RestResponse> future = new FutureCallback<RestResponse>();
+    final FutureCallback<RestResponse> future = new FutureCallback<>();
     restRequest(request, requestContext, future);
     return future;
   }

d2/src/main/java/com/linkedin/d2/balancer/clients/DegraderTrackerClientImpl.java

@@ -105,7 +105,7 @@ public DegraderTrackerClientImpl(URI uri, Map<Integer, PartitionData> partitionD
      * However, now it becomes harder to have different configurations for different partitions.
      */
     int mapSize = partitionDataMap.size();
-    Map<Integer, PartitionState>partitionStates = new HashMap<Integer, PartitionState>(mapSize * 2);
+    Map<Integer, PartitionState>partitionStates = new HashMap<>(mapSize * 2);
     config.setName("TrackerClient Degrader: " + uri);
     DegraderImpl degrader = new DegraderImpl(config);
     DegraderControl degraderControl = new DegraderControl(degrader);

d2/src/main/java/com/linkedin/d2/balancer/config/ConfigWriter.java

@@ -73,7 +73,7 @@ public void writeConfig() throws ExecutionException, TimeoutException, Interrupt
   {
     long startTime = System.currentTimeMillis();
 
-    FutureCallback<None> callback = new FutureCallback<None>();
+    FutureCallback<None> callback = new FutureCallback<>();
     _store.start(callback);
     callback.get(_timeout, _timeoutUnit);
 
@@ -116,7 +116,7 @@ public void onError(Throwable e)
       throw new TimeoutException();
     }
 
-    FutureCallback<None> shutdownCallback = new FutureCallback<None>();
+    FutureCallback<None> shutdownCallback = new FutureCallback<>();
     _store.shutdown(shutdownCallback);
     shutdownCallback.get(_timeout, _timeoutUnit);
 
@@ -134,7 +134,7 @@ public static Map<String,Object> merge(Map<String,Object> source, Map<String,Obj
     {
       defaultMap = Collections.emptyMap();
     }
-    Map<String,Object> result = new HashMap<String,Object>(defaultMap);
+    Map<String, Object> result = new HashMap<>(defaultMap);
     for (String key : source.keySet())
     {
       Object sourceValue = source.get(key);

d2/src/main/java/com/linkedin/d2/balancer/config/PartitionDataFactory.java

@@ -31,7 +31,7 @@ public class PartitionDataFactory
 {
   public static Map<Integer, PartitionData> createPartitionDataMap(Map<String, Object> sourceMap)
   {
-    Map<Integer, PartitionData> map = new HashMap<Integer, PartitionData>();
+    Map<Integer, PartitionData> map = new HashMap<>();
     if (sourceMap != null)
     {
       for (Map.Entry<String, Object> entry : sourceMap.entrySet())

d2/src/main/java/com/linkedin/d2/balancer/properties/AllowedClientPropertyKeys.java

@@ -48,7 +48,7 @@ public enum AllowedClientPropertyKeys
   private static final Set<String> _allowedKeys;
   static
   {
-    _allowedKeys = new HashSet<String>();
+    _allowedKeys = new HashSet<>();
     for (AllowedClientPropertyKeys propertyKey: AllowedClientPropertyKeys.values())
     {
       _allowedKeys.add(propertyKey._keyName);

d2/src/main/java/com/linkedin/d2/balancer/properties/ServicePropertiesJsonSerializer.java

@@ -213,7 +213,7 @@ public ServiceProperties fromMap(Map<String,Object> map)
     Set<URI> banned = new HashSet<>(bannedList);
     List<String> prioritizedSchemes = mapGetOrDefault(map, PropertyKeys.PRIORITIZED_SCHEMES, Collections.emptyList());
 
-    Map<String, Object> metadataProperties = new HashMap<String,Object>();
+    Map<String, Object> metadataProperties = new HashMap<>();
     String isDefaultService = mapGetOrDefault(map, PropertyKeys.IS_DEFAULT_SERVICE, null);
     if ("true".equalsIgnoreCase(isDefaultService))
     {

d2/src/main/java/com/linkedin/d2/balancer/properties/UriProperties.java

@@ -46,23 +46,22 @@ public UriProperties(String clusterName,
                        Map<URI, Map<String, Object>> uriSpecificProperties)
   {
     _clusterName = clusterName;
-    Map<URI, Map<Integer, PartitionData>> partitionDescriptionsMap = new HashMap<URI, Map<Integer, PartitionData>>(partitionDescriptions.size() * 2);
+    Map<URI, Map<Integer, PartitionData>> partitionDescriptionsMap = new HashMap<>(partitionDescriptions.size() * 2);
     for (Map.Entry<URI, Map<Integer, PartitionData>> entry : partitionDescriptions.entrySet())
     {
-      partitionDescriptionsMap.put(entry.getKey(), Collections.unmodifiableMap(
-          new HashMap<Integer, PartitionData>(entry.getValue())));
+      partitionDescriptionsMap.put(entry.getKey(), Collections.unmodifiableMap(new HashMap<>(entry.getValue())));
     }
     _partitionDesc = Collections.unmodifiableMap(partitionDescriptionsMap);
 
     // group uris by scheme and partition
-    HashMap<String, Map<Integer, Set<URI>>> urisBySchemeAndPartition = new HashMap<String, Map<Integer, Set<URI>>>();
+    HashMap<String, Map<Integer, Set<URI>>> urisBySchemeAndPartition = new HashMap<>();
     for (Map.Entry<URI, Map<Integer, PartitionData>> entry : _partitionDesc.entrySet())
     {
       final URI uri = entry.getKey();
       Map<Integer, Set<URI>> map= urisBySchemeAndPartition.get(uri.getScheme());
       if (map == null)
       {
-        map = new HashMap<Integer, Set<URI>>();
+        map = new HashMap<>();
         urisBySchemeAndPartition.put(uri.getScheme(), map);
       }
 
@@ -72,7 +71,7 @@ public UriProperties(String clusterName,
         Set<URI> uriSet = map.get(partitionId);
         if (uriSet == null)
         {
-          uriSet = new HashSet<URI>();
+          uriSet = new HashSet<>();
           map.put(partitionId, uriSet);
         }
         uriSet.add(uri);