[Issue 12271][Modernizer] Add Maven Modernizer plugin in pulsar-proxy module

pom.xml

@@ -248,6 +248,7 @@ flexible messaging model and an intuitive client API.</description>
     <j2objc-annotations.version>1.3</j2objc-annotations.version>
     <lightproto-maven-plugin.version>0.4</lightproto-maven-plugin.version>
     <dependency-check-maven.version>6.1.6</dependency-check-maven.version>
+    <modernizer-maven-plugin.version>2.3.0</modernizer-maven-plugin.version>
 
     <!-- Used to configure rename.netty.native. Libs -->
     <rename.netty.native.libs>rename-netty-native-libs.sh</rename.netty.native.libs>

pulsar-proxy/pom.xml

@@ -179,6 +179,27 @@
           <artifactId>log4j-core</artifactId>
       </dependency>
   </dependencies>
+  <build>
+    <plugins>
+      <plugin>
+        <groupId>org.gaul</groupId>
+        <artifactId>modernizer-maven-plugin</artifactId>
+        <version>${modernizer-maven-plugin.version}</version>
+        <configuration>
+          <failOnViolations>true</failOnViolations>
+          <javaVersion>8</javaVersion>
+        </configuration>
+        <executions>
+          <execution>
+            <id>modernizer</id>
+            <goals>
+              <goal>modernizer</goal>
+            </goals>
+          </execution>
+        </executions>
+      </plugin>
+    </plugins>
+  </build>
   <profiles>
     <profile>
       <!-- enables builds with -Dmaven.test.skip=true -->

pulsar-proxy/src/main/java/org/apache/pulsar/proxy/extensions/ProxyExtensions.java

@@ -19,10 +19,10 @@
 package org.apache.pulsar.proxy.extensions;
 
 import com.google.common.collect.ImmutableMap;
-import com.google.common.collect.Maps;
-import com.google.common.collect.Sets;
 import io.netty.channel.ChannelInitializer;
 import io.netty.channel.socket.SocketChannel;
+import java.util.HashMap;
+import java.util.HashSet;
 import lombok.extern.slf4j.Slf4j;
 import org.apache.pulsar.proxy.server.ProxyConfiguration;
 import org.apache.pulsar.proxy.server.ProxyService;
@@ -108,8 +108,8 @@ public void initialize(ProxyConfiguration conf) throws Exception {
     }
 
     public Map<String, Map<InetSocketAddress, ChannelInitializer<SocketChannel>>> newChannelInitializers() {
-        Map<String, Map<InetSocketAddress, ChannelInitializer<SocketChannel>>> channelInitializers = Maps.newHashMap();
-        Set<InetSocketAddress> addresses = Sets.newHashSet();
+        Map<String, Map<InetSocketAddress, ChannelInitializer<SocketChannel>>> channelInitializers = new HashMap<>();
+        Set<InetSocketAddress> addresses = new HashSet<>();
 
         for (Map.Entry<String, ProxyExtensionWithClassLoader> extension : extensions.entrySet()) {
             Map<InetSocketAddress, ChannelInitializer<SocketChannel>> initializers =

pulsar-proxy/src/main/java/org/apache/pulsar/proxy/server/ParserProxyHandler.java

@@ -20,6 +20,7 @@
 package org.apache.pulsar.proxy.server;
 
 import java.nio.charset.StandardCharsets;
+import java.util.ArrayList;
 import java.util.List;
 import java.util.Map;
 import java.util.concurrent.ConcurrentHashMap;
@@ -33,8 +34,6 @@
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
-import com.google.common.collect.Lists;
-
 import io.netty.buffer.ByteBuf;
 import io.netty.buffer.ByteBufUtil;
 import io.netty.buffer.CompositeByteBuf;
@@ -96,7 +95,7 @@ private void logging(Channel conn, BaseCommand.Type cmdtype, String info, List<R
 
     public void channelRead(ChannelHandlerContext ctx, Object msg) {
         TopicName topicName ;
-        List<RawMessage> messages = Lists.newArrayList();
+        List<RawMessage> messages = new ArrayList<>();
         ByteBuf buffer = (ByteBuf)(msg);
 
         try {

pulsar-proxy/src/main/java/org/apache/pulsar/proxy/server/ProxyConfiguration.java

@@ -18,14 +18,14 @@
  */
 package org.apache.pulsar.proxy.server;
 
-import com.google.common.collect.Sets;
-
 import java.util.HashMap;
+import java.util.HashSet;
 import java.util.List;
 import java.util.Map;
 import java.util.Optional;
 import java.util.Properties;
 import java.util.Set;
+import java.util.TreeSet;
 import java.util.stream.Collectors;
 import java.util.regex.Matcher;
 import java.util.regex.Pattern;
@@ -203,7 +203,7 @@ public class ProxyConfiguration implements PulsarConfiguration {
             + " `super-user`, meaning they will be able to do all admin operations and publish"
             + " & consume from all topics"
     )
-    private Set<String> superUserRoles = Sets.newTreeSet();
+    private Set<String> superUserRoles = new TreeSet<>();
 
     @FieldContext(
         category = CATEGORY_AUTHENTICATION,
@@ -214,7 +214,7 @@ public class ProxyConfiguration implements PulsarConfiguration {
         category = CATEGORY_AUTHENTICATION,
         doc = "Authentication provider name list (a comma-separated list of class names"
     )
-    private Set<String> authenticationProviders = Sets.newTreeSet();
+    private Set<String> authenticationProviders = new TreeSet<>();
     @FieldContext(
         category = CATEGORY_AUTHORIZATION,
         doc = "Whether authorization is enforced by the Pulsar proxy"
@@ -346,14 +346,14 @@ public class ProxyConfiguration implements PulsarConfiguration {
             + " (a comma-separated list of protocol names).\n\n"
             + "Examples:- [TLSv1.3, TLSv1.2]"
     )
-    private Set<String> tlsProtocols = Sets.newTreeSet();
+    private Set<String> tlsProtocols = new TreeSet<>();
     @FieldContext(
         category = CATEGORY_TLS,
         doc = "Specify the tls cipher the proxy will use to negotiate during TLS Handshake"
             + " (a comma-separated list of ciphers).\n\n"
             + "Examples:- [TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256]"
     )
-    private Set<String> tlsCiphers = Sets.newTreeSet();
+    private Set<String> tlsCiphers = new TreeSet<>();
     @FieldContext(
         category = CATEGORY_TLS,
         doc = "Whether client certificates are required for TLS.\n\n"
@@ -449,23 +449,23 @@ public class ProxyConfiguration implements PulsarConfiguration {
                   + "Examples:- [TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256].\n"
                   + " used by the Pulsar proxy to authenticate with Pulsar brokers"
     )
-    private Set<String> brokerClientTlsCiphers = Sets.newTreeSet();
+    private Set<String> brokerClientTlsCiphers = new TreeSet<>();
     @FieldContext(
             category = CATEGORY_KEYSTORE_TLS,
             doc = "Specify the tls protocols the broker will use to negotiate during TLS handshake"
                   + " (a comma-separated list of protocol names).\n\n"
                   + "Examples:- [TLSv1.3, TLSv1.2] \n"
                   + " used by the Pulsar proxy to authenticate with Pulsar brokers"
     )
-    private Set<String> brokerClientTlsProtocols = Sets.newTreeSet();
+    private Set<String> brokerClientTlsProtocols = new TreeSet<>();
 
     /***** --- HTTP --- ****/
 
     @FieldContext(
         category = CATEGORY_HTTP,
         doc = "Http directs to redirect to non-pulsar services"
     )
-    private Set<HttpReverseProxyConfig> httpReverseProxyConfigs = Sets.newHashSet();
+    private Set<HttpReverseProxyConfig> httpReverseProxyConfigs = new HashSet<>();
 
     @FieldContext(
         minValue = 1,
@@ -523,13 +523,13 @@ public class ProxyConfiguration implements PulsarConfiguration {
             category = CATEGORY_PLUGIN,
             doc = "List of proxy additional servlet to load, which is a list of proxy additional servlet names"
     )
-    private Set<String> proxyAdditionalServlets = Sets.newTreeSet();
+    private Set<String> proxyAdditionalServlets = new TreeSet<>();
 
     @FieldContext(
             category = CATEGORY_PLUGIN,
             doc = "List of proxy additional servlet to load, which is a list of proxy additional servlet names"
     )
-    private Set<String> additionalServlets = Sets.newTreeSet();
+    private Set<String> additionalServlets = new TreeSet<>();
 
     @FieldContext(
             category =  CATEGORY_HTTP,
@@ -579,7 +579,7 @@ public class ProxyConfiguration implements PulsarConfiguration {
             category = CATEGORY_PLUGIN,
             doc = "List of messaging protocols to load, which is a list of extension names"
     )
-    private Set<String> proxyExtensions = Sets.newTreeSet();
+    private Set<String> proxyExtensions = new TreeSet<>();
 
     /***** --- WebSocket --- ****/
     @FieldContext(

pulsar-proxy/src/main/java/org/apache/pulsar/proxy/server/ProxyService.java

@@ -18,9 +18,8 @@
  */
 package org.apache.pulsar.proxy.server;
 
-import static com.google.common.base.Preconditions.checkNotNull;
+import static java.util.Objects.requireNonNull;
 import static org.apache.commons.lang3.StringUtils.isBlank;
-import com.google.common.collect.Maps;
 import com.google.common.collect.Sets;
 import io.netty.bootstrap.ServerBootstrap;
 import io.netty.channel.AdaptiveRecvByteBufAllocator;
@@ -41,6 +40,7 @@
 import java.util.Map;
 import java.util.Optional;
 import java.util.Set;
+import java.util.concurrent.ConcurrentHashMap;
 import java.util.concurrent.Executors;
 import java.util.concurrent.ScheduledExecutorService;
 import java.util.concurrent.Semaphore;
@@ -131,11 +131,11 @@ public class ProxyService implements Closeable {
 
     public ProxyService(ProxyConfiguration proxyConfig,
                         AuthenticationService authenticationService) throws Exception {
-        checkNotNull(proxyConfig);
+        requireNonNull(proxyConfig);
         this.proxyConfig = proxyConfig;
         this.timer = new HashedWheelTimer(new DefaultThreadFactory("pulsar-timer", Thread.currentThread().isDaemon()), 1, TimeUnit.MILLISECONDS);
         this.clientCnxs = Sets.newConcurrentHashSet();
-        this.topicStats = Maps.newConcurrentMap();
+        this.topicStats = new ConcurrentHashMap<>();
 
         this.lookupRequestSemaphore = new AtomicReference<Semaphore>(
                 new Semaphore(proxyConfig.getMaxConcurrentLookupRequests(), false));

pulsar-proxy/src/main/java/org/apache/pulsar/proxy/server/WebServer.java

@@ -18,8 +18,6 @@
  */
 package org.apache.pulsar.proxy.server;
 
-import com.google.common.collect.Lists;
-
 import io.prometheus.client.jetty.JettyStatisticsCollector;
 import java.io.IOException;
 import java.net.URI;
@@ -69,8 +67,8 @@ public class WebServer {
     private final Server server;
     private final WebExecutorThreadPool webServiceExecutor;
     private final AuthenticationService authenticationService;
-    private final List<String> servletPaths = Lists.newArrayList();
-    private final List<Handler> handlers = Lists.newArrayList();
+    private final List<String> servletPaths = new ArrayList<>();
+    private final List<Handler> handlers = new ArrayList<>();
     private final ProxyConfiguration config;
     protected int externalServicePort;
     private URI serviceURI = null;
@@ -84,7 +82,7 @@ public WebServer(ProxyConfiguration config, AuthenticationService authentication
         this.authenticationService = authenticationService;
         this.config = config;
 
-        List<ServerConnector> connectors = Lists.newArrayList();
+        List<ServerConnector> connectors = new ArrayList<>();
 
         HttpConfiguration http_config = new HttpConfiguration();
         http_config.setOutputBufferSize(config.getHttpOutputBufferSize());

pulsar-proxy/src/main/java/org/apache/pulsar/proxy/stats/ProxyStats.java

@@ -18,6 +18,7 @@
  */
 package org.apache.pulsar.proxy.stats;
 
+import java.util.ArrayList;
 import java.util.List;
 import java.util.Map;
 import java.util.Optional;
@@ -34,8 +35,6 @@
 
 import org.apache.pulsar.proxy.server.ProxyService;
 
-import com.google.common.collect.Lists;
-
 import io.netty.channel.Channel;
 import io.swagger.annotations.Api;
 import io.swagger.annotations.ApiOperation;
@@ -59,7 +58,7 @@ public class ProxyStats {
     @ApiOperation(value = "Proxy stats api to get info for live connections", response = List.class, responseContainer = "List")
     @ApiResponses(value = { @ApiResponse(code = 503, message = "Proxy service is not initialized") })
     public List<ConnectionStats> metrics() {
-        List<ConnectionStats> stats = Lists.newArrayList();
+        List<ConnectionStats> stats = new ArrayList<>();
         proxyService().getClientCnxs().forEach(cnx -> {
             if (cnx.getDirectProxyHandler() == null) {
                 return;

pulsar-proxy/src/test/java/org/apache/pulsar/proxy/server/ProxyAuthenticatedProducerConsumerTest.java

@@ -189,7 +189,7 @@ public void testTlsSyncProducerAndConsumer() throws Exception {
         }
 
         Message<byte[]> msg = null;
-        Set<String> messageSet = Sets.newHashSet();
+        Set<String> messageSet = new HashSet<>();
         int count = 0;
         for (int i = 0; i < 10; i++) {
             msg = consumer.receive(5, TimeUnit.SECONDS);

pulsar-proxy/src/test/java/org/apache/pulsar/proxy/server/ProxyKeyStoreTlsTestWithAuth.java

@@ -18,7 +18,7 @@
  */
 package org.apache.pulsar.proxy.server;
 
-import static com.google.common.base.Preconditions.checkNotNull;
+import static java.util.Objects.requireNonNull;
 import static org.mockito.Mockito.doReturn;
 
 import com.google.common.collect.Sets;
@@ -195,7 +195,7 @@ public void testPartitions() throws Exception {
 
         for (int i = 0; i < 10; i++) {
             Message<byte[]> msg = consumer.receive(1, TimeUnit.SECONDS);
-            checkNotNull(msg);
+            requireNonNull(msg);
         }
     }
 

pulsar-proxy/src/test/java/org/apache/pulsar/proxy/server/ProxyKeyStoreTlsTestWithoutAuth.java

@@ -18,7 +18,7 @@
  */
 package org.apache.pulsar.proxy.server;
 
-import static com.google.common.base.Preconditions.checkNotNull;
+import static java.util.Objects.requireNonNull;
 import static org.mockito.Mockito.doReturn;
 
 import java.util.HashMap;
@@ -180,7 +180,7 @@ public void testPartitions() throws Exception {
 
         for (int i = 0; i < 10; i++) {
             Message<byte[]> msg = consumer.receive(1, TimeUnit.SECONDS);
-            checkNotNull(msg);
+            requireNonNull(msg);
         }
     }
 

pulsar-proxy/src/test/java/org/apache/pulsar/proxy/server/ProxyParserTest.java

@@ -19,8 +19,8 @@
 package org.apache.pulsar.proxy.server;
 
 import static com.google.common.base.Preconditions.checkArgument;
-import static com.google.common.base.Preconditions.checkNotNull;
 import static java.nio.charset.StandardCharsets.UTF_8;
+import static java.util.Objects.requireNonNull;
 import static org.mockito.Mockito.doReturn;
 import static org.testng.Assert.assertEquals;
 
@@ -128,7 +128,7 @@ public void testProducerConsumer() throws Exception {
 
         for (int i = 0; i < 10; i++) {
             Message<byte[]> msg = consumer.receive(1, TimeUnit.SECONDS);
-            checkNotNull(msg);
+            requireNonNull(msg);
             consumer.acknowledge(msg);
         }
 
@@ -162,7 +162,7 @@ public void testPartitions() throws Exception {
 
         for (int i = 0; i < 10; i++) {
             Message<byte[]> msg = consumer.receive(1, TimeUnit.SECONDS);
-            checkNotNull(msg);
+            requireNonNull(msg);
         }
     }
 
@@ -231,7 +231,7 @@ public void testProtocolVersionAdvertisement() throws Exception {
 
         for (int i = 0; i < 10; i++) {
             Message<byte[]> msg = consumer.receive(10, TimeUnit.SECONDS);
-            checkNotNull(msg);
+            requireNonNull(msg);
             consumer.acknowledge(msg);
         }
 

pulsar-proxy/src/test/java/org/apache/pulsar/proxy/server/ProxyStatsTest.java

@@ -18,7 +18,7 @@
  */
 package org.apache.pulsar.proxy.server;
 
-import static com.google.common.base.Preconditions.checkNotNull;
+import static java.util.Objects.requireNonNull;
 import static org.mockito.Mockito.doReturn;
 import static org.testng.Assert.assertEquals;
 import static org.testng.Assert.assertNotNull;
@@ -120,7 +120,7 @@ public void testConnectionsStats() throws Exception {
 
         for (int i = 0; i < totalMessages; i++) {
             Message<byte[]> msg = consumer.receive(1, TimeUnit.SECONDS);
-            checkNotNull(msg);
+            requireNonNull(msg);
             consumer.acknowledge(msg);
         }
 
@@ -169,7 +169,7 @@ public void testTopicStats() throws Exception {
 
         for (int i = 0; i < totalMessages; i++) {
             Message<byte[]> msg = consumer.receive(1, TimeUnit.SECONDS);
-            checkNotNull(msg);
+            requireNonNull(msg);
             consumer.acknowledge(msg);
             msg = consumer2.receive(1, TimeUnit.SECONDS);
         }