Optimize code (#3600)

apm-sniffer/apm-agent-core/src/main/java/org/apache/skywalking/apm/agent/core/remote/AgentIDDecorator.java

@@ -57,7 +57,7 @@ public class AgentIDDecorator implements ChannelDecorator {
                     Attributes mainAttribs = manifest.getMainAttributes();
                     String projectName = mainAttribs.getValue("Implementation-Vendor-Id");
                     if (projectName != null) {
-                        if (projectName.equals("org.apache.skywalking")) {
+                        if ("org.apache.skywalking".equals(projectName)) {
                             version = mainAttribs.getValue("Implementation-Version");
                         }
                     }

apm-sniffer/apm-sdk-plugin/spring-plugins/core-patch/src/main/java/org/apache/skywalking/apm/plugin/spring/patch/GetPropertyDescriptorsInterceptor.java

@@ -44,7 +44,7 @@ public class GetPropertyDescriptorsInterceptor implements InstanceMethodsAroundI
         if (EnhancedInstance.class.isAssignableFrom(((BeanWrapperImpl)objInst).getRootClass())) {
             List<PropertyDescriptor> newPropertyDescriptors = new ArrayList<PropertyDescriptor>();
             for (PropertyDescriptor descriptor : propertyDescriptors) {
-                if (!descriptor.getName().equals("skyWalkingDynamicField")) {
+                if (!"skyWalkingDynamicField".equals(descriptor.getName())) {
                     newPropertyDescriptors.add(descriptor);
                 }
             }

oap-server/server-core/src/main/java/org/apache/skywalking/oap/server/core/RunningMode.java

@@ -43,7 +43,7 @@ public class RunningMode {
      * @return true if in this status
      */
     public static boolean isInitMode() {
-        return MODE.equals("init");
+        return "init".equals(MODE);
     }
 
     /**
@@ -51,6 +51,6 @@ public class RunningMode {
      * @return true if in this status.
      */
     public static boolean isNoInitMode() {
-        return MODE.equals("no-init");
+        return "no-init".equals(MODE);
     }
 }

oap-server/server-core/src/main/java/org/apache/skywalking/oap/server/core/analysis/data/LimitedSizeDataCollection.java

@@ -35,7 +35,7 @@ public class LimitedSizeDataCollection<STORAGE_DATA extends ComparableStorageDat
         this.limitedSize = limitedSize;
     }
 
-    public void finishWriting() {
+    @Override public void finishWriting() {
         writing = false;
     }
 

oap-server/server-core/src/main/java/org/apache/skywalking/oap/server/core/analysis/data/MergeDataCollection.java

@@ -36,7 +36,7 @@ public class MergeDataCollection<STREAM_DATA extends StreamData> implements SWCo
         this.reading = false;
     }
 
-    public void finishWriting() {
+    @Override public void finishWriting() {
         writing = false;
     }
 

oap-server/server-core/src/main/java/org/apache/skywalking/oap/server/core/analysis/data/NonMergeDataCollection.java

@@ -36,7 +36,7 @@ public class NonMergeDataCollection<STORAGE_DATA extends StorageData> implements
         this.reading = false;
     }
 
-    public void finishWriting() {
+    @Override public void finishWriting() {
         writing = false;
     }