diff --git a/apm-sniffer/apm-agent-core/src/main/java/org/skywalking/apm/agent/core/context/trace/TraceSegment.java b/apm-sniffer/apm-agent-core/src/main/java/org/skywalking/apm/agent/core/context/trace/TraceSegment.java
index 8577a4297..000e71956 100644
--- a/apm-sniffer/apm-agent-core/src/main/java/org/skywalking/apm/agent/core/context/trace/TraceSegment.java
+++ b/apm-sniffer/apm-agent-core/src/main/java/org/skywalking/apm/agent/core/context/trace/TraceSegment.java
@@ -2,14 +2,11 @@ package org.skywalking.apm.agent.core.context.trace;
 
 import java.util.LinkedList;
 import java.util.List;
-import org.skywalking.apm.agent.core.conf.Config;
 import org.skywalking.apm.agent.core.conf.RemoteDownstreamConfig;
 import org.skywalking.apm.agent.core.context.ids.DistributedTraceId;
 import org.skywalking.apm.agent.core.context.ids.DistributedTraceIds;
 import org.skywalking.apm.agent.core.context.ids.GlobalIdGenerator;
 import org.skywalking.apm.agent.core.context.ids.NewDistributedTraceId;
-import org.skywalking.apm.agent.core.dictionary.DictionaryManager;
-import org.skywalking.apm.agent.core.dictionary.PossibleFound;
 import org.skywalking.apm.logging.ILog;
 import org.skywalking.apm.logging.LogManager;
 import org.skywalking.apm.network.proto.TraceSegmentObject;
diff --git a/apm-sniffer/apm-agent-core/src/main/java/org/skywalking/apm/agent/core/jvm/JVMService.java b/apm-sniffer/apm-agent-core/src/main/java/org/skywalking/apm/agent/core/jvm/JVMService.java
index d4faec75a..7b8f759ce 100644
--- a/apm-sniffer/apm-agent-core/src/main/java/org/skywalking/apm/agent/core/jvm/JVMService.java
+++ b/apm-sniffer/apm-agent-core/src/main/java/org/skywalking/apm/agent/core/jvm/JVMService.java
@@ -31,7 +31,7 @@ import static org.skywalking.apm.agent.core.remote.GRPCChannelStatus.CONNECTED;
  * @author wusheng
  */
 public class JVMService implements BootService, Runnable {
-    private static ILog logger = LogManager.getLogger(JVMService.class);
+    private static final ILog logger = LogManager.getLogger(JVMService.class);
     private ReentrantLock lock = new ReentrantLock();
     private volatile LinkedList<JVMMetric> buffer = new LinkedList<JVMMetric>();
     private SimpleDateFormat sdf = new SimpleDateFormat("ss");
diff --git a/apm-sniffer/apm-sdk-plugin/pom.xml b/apm-sniffer/apm-sdk-plugin/pom.xml
index 6276015f3..1f32acfc9 100644
--- a/apm-sniffer/apm-sdk-plugin/pom.xml
+++ b/apm-sniffer/apm-sdk-plugin/pom.xml
@@ -38,12 +38,6 @@
             <artifactId>apm-agent-core</artifactId>
             <version>${project.version}</version>
         </dependency>
-        <dependency>
-            <groupId>org.skywalking</groupId>
-            <artifactId>apm-sniffer-mock</artifactId>
-            <version>${project.version}</version>
-            <scope>test</scope>
-        </dependency>
     </dependencies>
 
     <build>