Remove some unused variables (#5598)

apm-commons/apm-datacarrier/src/main/java/org/apache/skywalking/apm/commons/datacarrier/DataCarrier.java

@@ -31,8 +31,6 @@ import org.apache.skywalking.apm.commons.datacarrier.partition.SimpleRollingPart
  * DataCarrier main class. use this instance to set Producer/Consumer Model.
  */
 public class DataCarrier<T> {
-    private final int bufferSize;
-    private final int channelSize;
     private Channels<T> channels;
     private IDriver driver;
     private String name;
@@ -47,9 +45,9 @@ public class DataCarrier<T> {
 
     public DataCarrier(String name, String envPrefix, int channelSize, int bufferSize) {
         this.name = name;
-        this.bufferSize = EnvUtil.getInt(envPrefix + "_BUFFER_SIZE", bufferSize);
-        this.channelSize = EnvUtil.getInt(envPrefix + "_CHANNEL_SIZE", channelSize);
-        channels = new Channels<T>(channelSize, bufferSize, new SimpleRollingPartitioner<T>(), BufferStrategy.BLOCKING);
+        bufferSize = EnvUtil.getInt(envPrefix + "_BUFFER_SIZE", bufferSize);
+        channelSize = EnvUtil.getInt(envPrefix + "_CHANNEL_SIZE", channelSize);
+        channels = new Channels<>(channelSize, bufferSize, new SimpleRollingPartitioner<T>(), BufferStrategy.BLOCKING);
     }
 
     /**

apm-commons/apm-datacarrier/src/main/java/org/apache/skywalking/apm/commons/datacarrier/partition/ProducerThreadPartitioner.java

@@ -22,15 +22,9 @@ package org.apache.skywalking.apm.commons.datacarrier.partition;
  * use threadid % total to partition
  */
 public class ProducerThreadPartitioner<T> implements IDataPartitioner<T> {
-    private int retryTime = 3;
-
     public ProducerThreadPartitioner() {
     }
 
-    public ProducerThreadPartitioner(int retryTime) {
-        this.retryTime = retryTime;
-    }
-
     @Override
     public int partition(int total, T data) {
         return (int) Thread.currentThread().getId() % total;

apm-commons/apm-datacarrier/src/test/java/org/apache/skywalking/apm/commons/datacarrier/DataCarrierTest.java

@@ -33,11 +33,7 @@ import org.powermock.api.support.membermodification.MemberModifier;
 public class DataCarrierTest {
     @Test
     public void testCreateDataCarrier() throws IllegalAccessException {
-        DataCarrier<SampleData> carrier = new DataCarrier<SampleData>(5, 100);
-        Assert.assertEquals(((Integer) (MemberModifier.field(DataCarrier.class, "bufferSize")
-                                                      .get(carrier))).intValue(), 100);
-        Assert.assertEquals(((Integer) (MemberModifier.field(DataCarrier.class, "channelSize")
-                                                      .get(carrier))).intValue(), 5);
+        DataCarrier<SampleData> carrier = new DataCarrier<>(5, 100);
 
         Channels<SampleData> channels = (Channels<SampleData>) (MemberModifier.field(DataCarrier.class, "channels")
                                                                               .get(carrier));
@@ -116,39 +112,36 @@ public class DataCarrierTest {
         }
 
         long time1 = System.currentTimeMillis();
-        new Thread(new Runnable() {
-            @Override
-            public void run() {
-                try {
-                    Thread.sleep(3000);
-                } catch (InterruptedException e) {
-                    e.printStackTrace();
-                }
-                IConsumer<SampleData> consumer = new IConsumer<SampleData>() {
-                    int i = 0;
+        new Thread(() -> {
+            try {
+                Thread.sleep(3000);
+            } catch (InterruptedException e) {
+                e.printStackTrace();
+            }
+            IConsumer<SampleData> consumer = new IConsumer<SampleData>() {
+                int i = 0;
 
-                    @Override
-                    public void init() {
+                @Override
+                public void init() {
 
-                    }
+                }
 
-                    @Override
-                    public void consume(List<SampleData> data) {
+                @Override
+                public void consume(List<SampleData> data) {
 
-                    }
+                }
 
-                    @Override
-                    public void onError(List<SampleData> data, Throwable t) {
+                @Override
+                public void onError(List<SampleData> data, Throwable t) {
 
-                    }
+                }
 
-                    @Override
-                    public void onExit() {
+                @Override
+                public void onExit() {
 
-                    }
-                };
-                carrier.consume(consumer, 1);
-            }
+                }
+            };
+            carrier.consume(consumer, 1);
         }).start();
 
         carrier.produce(new SampleData().setName("blocking-data"));

apm-sniffer/apm-sdk-plugin/elasticsearch-6.x-plugin/src/main/java/org/apache/skywalking/apm/plugin/elasticsearch/v6/interceptor/RestHighLevelClientClusterMethodsInterceptor.java

@@ -22,7 +22,6 @@ import java.lang.reflect.Method;
 import org.apache.skywalking.apm.agent.core.plugin.interceptor.enhance.EnhancedInstance;
 import org.apache.skywalking.apm.agent.core.plugin.interceptor.enhance.InstanceMethodsAroundInterceptor;
 import org.apache.skywalking.apm.agent.core.plugin.interceptor.enhance.MethodInterceptResult;
-import org.apache.skywalking.apm.plugin.elasticsearch.v6.RestClientEnhanceInfo;
 
 public class RestHighLevelClientClusterMethodsInterceptor implements InstanceMethodsAroundInterceptor {
 
@@ -36,7 +35,7 @@ public class RestHighLevelClientClusterMethodsInterceptor implements InstanceMet
     public Object afterMethod(EnhancedInstance objInst, Method method, Object[] allArguments,
         Class<?>[] argumentsTypes, Object ret) throws Throwable {
         if (ret instanceof EnhancedInstance) {
-            ((EnhancedInstance) ret).setSkyWalkingDynamicField((RestClientEnhanceInfo) (objInst.getSkyWalkingDynamicField()));
+            ((EnhancedInstance) ret).setSkyWalkingDynamicField(objInst.getSkyWalkingDynamicField());
         }
         return ret;
     }

apm-sniffer/apm-sdk-plugin/elasticsearch-6.x-plugin/src/main/java/org/apache/skywalking/apm/plugin/elasticsearch/v6/interceptor/RestHighLevelClientConInterceptor.java

@@ -19,8 +19,6 @@
 package org.apache.skywalking.apm.plugin.elasticsearch.v6.interceptor;
 
 import java.util.List;
-import org.apache.skywalking.apm.agent.core.logging.api.ILog;
-import org.apache.skywalking.apm.agent.core.logging.api.LogManager;
 import org.apache.skywalking.apm.agent.core.plugin.interceptor.enhance.EnhancedInstance;
 import org.apache.skywalking.apm.agent.core.plugin.interceptor.enhance.InstanceConstructorInterceptor;
 import org.apache.skywalking.apm.plugin.elasticsearch.v6.RestClientEnhanceInfo;
@@ -29,9 +27,6 @@ import org.elasticsearch.client.RestClient;
 import org.elasticsearch.client.RestClientBuilder;
 
 public class RestHighLevelClientConInterceptor implements InstanceConstructorInterceptor {
-
-    private static final ILog LOGGER = LogManager.getLogger(RestHighLevelClientConInterceptor.class);
-
     @Override
     public void onConstruct(EnhancedInstance objInst, Object[] allArguments) {
         RestClientBuilder restClientBuilder = (RestClientBuilder) (allArguments[0]);

apm-sniffer/apm-sdk-plugin/mongodb-2.x-plugin/src/main/java/org/apache/skywalking/apm/plugin/mongodb/v2/MongoDBCollectionMethodInterceptor.java

@@ -83,12 +83,11 @@ public class MongoDBCollectionMethodInterceptor implements InstanceMethodsAround
 
     @Override
     public void onConstruct(EnhancedInstance objInst, Object[] allArguments) {
-        List<ServerAddress> servers = null;
         DB db = (DB) allArguments[0];
-        servers = db.getMongo().getAllAddress();
+        List<ServerAddress> servers = db.getMongo().getAllAddress();
         StringBuilder peers = new StringBuilder();
         for (ServerAddress address : servers) {
-            peers.append(address.getHost() + ":" + address.getPort() + ";");
+            peers.append(address.getHost()).append(":").append(address.getPort()).append(";");
         }
 
         objInst.setSkyWalkingDynamicField(peers.subSequence(0, peers.length() - 1).toString());

apm-sniffer/apm-sdk-plugin/sofarpc-plugin/src/main/java/org/apache/skywalking/apm/plugin/sofarpc/SofaRpcConsumerInterceptor.java

@@ -22,6 +22,7 @@ import com.alipay.sofa.rpc.client.ProviderInfo;
 import com.alipay.sofa.rpc.context.RpcInternalContext;
 import com.alipay.sofa.rpc.core.request.SofaRequest;
 import com.alipay.sofa.rpc.core.response.SofaResponse;
+import java.lang.reflect.Method;
 import org.apache.skywalking.apm.agent.core.context.CarrierItem;
 import org.apache.skywalking.apm.agent.core.context.ContextCarrier;
 import org.apache.skywalking.apm.agent.core.context.ContextManager;
@@ -33,27 +34,23 @@ import org.apache.skywalking.apm.agent.core.plugin.interceptor.enhance.InstanceM
 import org.apache.skywalking.apm.agent.core.plugin.interceptor.enhance.MethodInterceptResult;
 import org.apache.skywalking.apm.network.trace.component.ComponentsDefine;
 
-import java.lang.reflect.Method;
-
 public class SofaRpcConsumerInterceptor implements InstanceMethodsAroundInterceptor {
 
     public static final String SKYWALKING_PREFIX = "skywalking.";
 
     @Override
     public void beforeMethod(EnhancedInstance objInst, Method method, Object[] allArguments, Class<?>[] argumentsTypes,
-        MethodInterceptResult result) throws Throwable {
+                             MethodInterceptResult result) throws Throwable {
         SofaRequest sofaRequest = (SofaRequest) allArguments[0];
         RpcInternalContext rpcContext = RpcInternalContext.getContext();
 
         ProviderInfo providerInfo = rpcContext.getProviderInfo();
 
-        AbstractSpan span = null;
-
         final String host = providerInfo.getHost();
         final int port = providerInfo.getPort();
         final ContextCarrier contextCarrier = new ContextCarrier();
         final String operationName = generateOperationName(providerInfo, sofaRequest);
-        span = ContextManager.createExitSpan(operationName, contextCarrier, host + ":" + port);
+        AbstractSpan span = ContextManager.createExitSpan(operationName, contextCarrier, host + ":" + port);
         CarrierItem next = contextCarrier.items();
         while (next.hasNext()) {
             next = next.next();
@@ -69,7 +66,7 @@ public class SofaRpcConsumerInterceptor implements InstanceMethodsAroundIntercep
 
     @Override
     public Object afterMethod(EnhancedInstance objInst, Method method, Object[] allArguments, Class<?>[] argumentsTypes,
-        Object ret) throws Throwable {
+                              Object ret) throws Throwable {
         SofaResponse result = (SofaResponse) ret;
         if (result != null && result.isError()) {
             dealException((Throwable) result.getAppResponse());
@@ -81,7 +78,7 @@ public class SofaRpcConsumerInterceptor implements InstanceMethodsAroundIntercep
 
     @Override
     public void handleMethodException(EnhancedInstance objInst, Method method, Object[] allArguments,
-        Class<?>[] argumentsTypes, Throwable t) {
+                                      Class<?>[] argumentsTypes, Throwable t) {
         dealException(t);
     }
 
@@ -101,9 +98,9 @@ public class SofaRpcConsumerInterceptor implements InstanceMethodsAroundIntercep
     private String generateOperationName(ProviderInfo providerInfo, SofaRequest sofaRequest) {
         StringBuilder operationName = new StringBuilder();
         operationName.append(sofaRequest.getInterfaceName());
-        operationName.append("." + sofaRequest.getMethodName() + "(");
+        operationName.append(".").append(sofaRequest.getMethodName()).append("(");
         for (String arg : sofaRequest.getMethodArgSigs()) {
-            operationName.append(arg + ",");
+            operationName.append(arg).append(",");
         }
 
         if (sofaRequest.getMethodArgs().length > 0) {
@@ -122,9 +119,9 @@ public class SofaRpcConsumerInterceptor implements InstanceMethodsAroundIntercep
      */
     private String generateRequestURL(ProviderInfo providerInfo, SofaRequest sofaRequest) {
         StringBuilder requestURL = new StringBuilder();
-        requestURL.append(providerInfo.getProtocolType() + "://");
+        requestURL.append(providerInfo.getProtocolType()).append("://");
         requestURL.append(providerInfo.getHost());
-        requestURL.append(":" + providerInfo.getPort() + "/");
+        requestURL.append(":").append(providerInfo.getPort()).append("/");
         requestURL.append(generateOperationName(providerInfo, sofaRequest));
         return requestURL.toString();
     }

apm-sniffer/apm-sdk-plugin/sofarpc-plugin/src/main/java/org/apache/skywalking/apm/plugin/sofarpc/SofaRpcProviderInterceptor.java

@@ -41,8 +41,6 @@ public class SofaRpcProviderInterceptor implements InstanceMethodsAroundIntercep
         MethodInterceptResult result) throws Throwable {
         SofaRequest sofaRequest = (SofaRequest) allArguments[0];
 
-        AbstractSpan span = null;
-
         ContextCarrier contextCarrier = new ContextCarrier();
         CarrierItem next = contextCarrier.items();
         while (next.hasNext()) {
@@ -55,7 +53,7 @@ public class SofaRpcProviderInterceptor implements InstanceMethodsAroundIntercep
                 next.setHeadValue("");
             }
         }
-        span = ContextManager.createEntrySpan(generateViewPoint(sofaRequest), contextCarrier);
+        AbstractSpan span = ContextManager.createEntrySpan(generateViewPoint(sofaRequest), contextCarrier);
 
         span.setComponent(ComponentsDefine.SOFARPC);
         SpanLayer.asRPCFramework(span);
@@ -95,9 +93,9 @@ public class SofaRpcProviderInterceptor implements InstanceMethodsAroundIntercep
     private String generateViewPoint(SofaRequest sofaRequest) {
         StringBuilder operationName = new StringBuilder();
         operationName.append(sofaRequest.getInterfaceName());
-        operationName.append("." + sofaRequest.getMethodName() + "(");
+        operationName.append(".").append(sofaRequest.getMethodName()).append("(");
         for (String arg : sofaRequest.getMethodArgSigs()) {
-            operationName.append(arg + ",");
+            operationName.append(arg).append(",");
         }
 
         if (sofaRequest.getMethodArgs().length > 0) {

oap-server/server-cluster-plugin/cluster-standalone-plugin/src/main/java/org/apache/skywalking/oap/server/cluster/plugin/standalone/ClusterModuleStandaloneProvider.java

@@ -25,13 +25,8 @@ import org.apache.skywalking.oap.server.library.module.ModuleConfig;
 import org.apache.skywalking.oap.server.library.module.ModuleProvider;
 import org.apache.skywalking.oap.server.library.module.ModuleStartException;
 import org.apache.skywalking.oap.server.library.module.ServiceNotProvidedException;
-import org.slf4j.Logger;
-import org.slf4j.LoggerFactory;
 
 public class ClusterModuleStandaloneProvider extends ModuleProvider {
-
-    private static final Logger LOGGER = LoggerFactory.getLogger(ClusterModuleStandaloneProvider.class);
-
     public ClusterModuleStandaloneProvider() {
         super();
     }