diff --git a/core/src/main/java/com/taobao/arthas/core/advisor/ArthasMethod.java b/core/src/main/java/com/taobao/arthas/core/advisor/ArthasMethod.java
index 6f3a74bc5..6d102a64b 100644
--- a/core/src/main/java/com/taobao/arthas/core/advisor/ArthasMethod.java
+++ b/core/src/main/java/com/taobao/arthas/core/advisor/ArthasMethod.java
@@ -92,7 +92,6 @@ public class ArthasMethod {
 
             if ("<init>".equals(this.methodName)) {
                 this.constructor = clazz.getDeclaredConstructor(argsClasses);
-                ;
             } else {
                 this.method = clazz.getDeclaredMethod(methodName, argsClasses);
             }
diff --git a/core/src/main/java/com/taobao/arthas/core/env/MutablePropertySources.java b/core/src/main/java/com/taobao/arthas/core/env/MutablePropertySources.java
index 909a70ee5..3a71b7dc1 100644
--- a/core/src/main/java/com/taobao/arthas/core/env/MutablePropertySources.java
+++ b/core/src/main/java/com/taobao/arthas/core/env/MutablePropertySources.java
@@ -195,9 +195,7 @@ public class MutablePropertySources implements PropertySources {
      * Remove the given property source if it is present.
      */
     protected void removeIfPresent(PropertySource<?> propertySource) {
-        if (this.propertySourceList.contains(propertySource)) {
-            this.propertySourceList.remove(propertySource);
-        }
+		this.propertySourceList.remove(propertySource);
     }
 
     /**
diff --git a/core/src/main/java/com/taobao/arthas/core/util/LogUtil.java b/core/src/main/java/com/taobao/arthas/core/util/LogUtil.java
index c9fd27ee9..f1e3c33cb 100644
--- a/core/src/main/java/com/taobao/arthas/core/util/LogUtil.java
+++ b/core/src/main/java/com/taobao/arthas/core/util/LogUtil.java
@@ -68,7 +68,6 @@ public class LogUtil {
             loggerContext.reset();
 
             String fileName = env.getProperty(FILE_NAME_PROPERTY);
-            ;
             if (fileName != null) {
                 loggerContext.putProperty(ARTHAS_LOG_FILE, fileName);
             }
diff --git a/core/src/main/java/com/taobao/arthas/core/util/ObjectUtils.java b/core/src/main/java/com/taobao/arthas/core/util/ObjectUtils.java
index 7fcbe4ad7..6a6d57b61 100644
--- a/core/src/main/java/com/taobao/arthas/core/util/ObjectUtils.java
+++ b/core/src/main/java/com/taobao/arthas/core/util/ObjectUtils.java
@@ -453,7 +453,7 @@ public abstract class ObjectUtils {
                         sb.append(", ");
                     }
 
-                    sb.append(String.valueOf(array[i]));
+                    sb.append(array[i]);
                 }
 
                 sb.append("}");
diff --git a/core/src/main/java/com/taobao/arthas/core/view/Ansi.java b/core/src/main/java/com/taobao/arthas/core/view/Ansi.java
index 481b7d999..35c1d1ae9 100644
--- a/core/src/main/java/com/taobao/arthas/core/view/Ansi.java
+++ b/core/src/main/java/com/taobao/arthas/core/view/Ansi.java
@@ -59,8 +59,6 @@ public class Ansi {
         }
     }
 
-    ;
-
     public static enum Attribute {
         RESET(0, "RESET"),
         INTENSITY_BOLD(1, "INTENSITY_BOLD"),
@@ -100,8 +98,6 @@ public class Ansi {
 
     }
 
-    ;
-
     public static enum Erase {
         FORWARD(0, "FORWARD"),
         BACKWARD(1, "BACKWARD"),
@@ -125,8 +121,6 @@ public class Ansi {
         }
     }
 
-    ;
-
     public static final String DISABLE = Ansi.class.getName() + ".disable";
 
     private static Callable<Boolean> detector = new Callable<Boolean>() {
diff --git a/tunnel-server/src/main/java/com/alibaba/arthas/tunnel/server/TunnelSocketFrameHandler.java b/tunnel-server/src/main/java/com/alibaba/arthas/tunnel/server/TunnelSocketFrameHandler.java
index 1f3d82d75..83f3dc81e 100644
--- a/tunnel-server/src/main/java/com/alibaba/arthas/tunnel/server/TunnelSocketFrameHandler.java
+++ b/tunnel-server/src/main/java/com/alibaba/arthas/tunnel/server/TunnelSocketFrameHandler.java
@@ -123,7 +123,7 @@ public class TunnelSocketFrameHandler extends SimpleChannelInboundHandler<WebSoc
         List<String> agentId = parameters.getOrDefault("id", Collections.emptyList());
 
         if (agentId.isEmpty()) {
-            logger.error("arthas agent id can not be null, parameters: ", parameters);
+            logger.error("arthas agent id can not be null, parameters: {}", parameters);
             throw new IllegalArgumentException("arthas agent id can not be null");
         }