fix(server): fix some issues of the distributed scheduler

Author: Tsukilc

hugegraph-server/hugegraph-core/src/main/java/org/apache/hugegraph/task/HugeServerInfo.java

@@ -17,6 +17,12 @@
 
 package org.apache.hugegraph.task;
 
+import java.util.ArrayList;
+import java.util.Date;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+
 import org.apache.hugegraph.HugeGraph;
 import org.apache.hugegraph.HugeGraphParams;
 import org.apache.hugegraph.backend.id.Id;
@@ -37,8 +43,6 @@
 import org.apache.tinkerpop.gremlin.structure.Vertex;
 import org.apache.tinkerpop.gremlin.structure.VertexProperty;
 
-import java.util.*;
-
 public class HugeServerInfo {
 
     // Unit millisecond

hugegraph-server/hugegraph-core/src/main/java/org/apache/hugegraph/task/StandardTaskScheduler.java

@@ -17,6 +17,17 @@
 
 package org.apache.hugegraph.task;
 
+import java.util.ArrayList;
+import java.util.Iterator;
+import java.util.List;
+import java.util.Map;
+import java.util.concurrent.Callable;
+import java.util.concurrent.ConcurrentHashMap;
+import java.util.concurrent.ExecutorService;
+import java.util.concurrent.Executors;
+import java.util.concurrent.Future;
+import java.util.concurrent.TimeoutException;
+
 import com.google.common.collect.ImmutableMap;
 import org.apache.hugegraph.HugeException;
 import org.apache.hugegraph.HugeGraph;
@@ -46,12 +57,6 @@
 import org.apache.tinkerpop.gremlin.structure.Vertex;
 import org.slf4j.Logger;
 
-import java.util.ArrayList;
-import java.util.Iterator;
-import java.util.List;
-import java.util.Map;
-import java.util.concurrent.*;
-
 public class StandardTaskScheduler implements TaskScheduler {
 
     private static final Logger LOG = Log.logger(StandardTaskScheduler.class);

hugegraph-server/hugegraph-core/src/main/java/org/apache/hugegraph/task/TaskManager.java

@@ -17,6 +17,14 @@
 
 package org.apache.hugegraph.task;
 
+import java.util.Map;
+import java.util.concurrent.Callable;
+import java.util.concurrent.ConcurrentHashMap;
+import java.util.concurrent.ExecutorService;
+import java.util.concurrent.ThreadPoolExecutor;
+import java.util.concurrent.TimeUnit;
+import java.util.concurrent.TimeoutException;
+
 import org.apache.hugegraph.HugeException;
 import org.apache.hugegraph.HugeGraphParams;
 import org.apache.hugegraph.concurrent.PausableScheduledThreadPool;
@@ -27,9 +35,6 @@
 import org.apache.hugegraph.util.Log;
 import org.slf4j.Logger;
 
-import java.util.Map;
-import java.util.concurrent.*;
-
 /**
  * Central task management system that coordinates task scheduling and execution.
  * Manages task schedulers for different graphs and handles role-based execution.