set ThreadLocalMap HashMap to ConcurrentMap; check valid in executeWithConnection

Author: JackShi148

src/main/java/com/alipay/oceanbase/rpc/table/ObTable.java

@@ -478,6 +478,10 @@ public ObPayload executeWithConnection(final ObPayload request,
                                            AtomicReference<ObTableConnection> connectionRef)
                                                                                             throws RemotingException,
                                                                                             InterruptedException {
+        if (!isValid()) {
+            log.warn("[latency monitor] The server is not available, server address: " + ip + ":" + port);
+            throw new ObTableServerConnectException("The server is not available, server address: " + ip + ":" + port);
+        }
         ObTableConnection connection;
         try {
             if (connectionRef.get() == null) {

src/main/java/com/alipay/oceanbase/rpc/threadlocal/ThreadLocalMap.java

@@ -21,8 +21,8 @@
 import com.alipay.oceanbase.rpc.util.TableClientLoggerFactory;
 import org.slf4j.Logger;
 
-import java.util.HashMap;
 import java.util.Map;
+import java.util.concurrent.ConcurrentHashMap;
 
 public class ThreadLocalMap {
 
@@ -112,7 +112,7 @@ public static void transmitContextMap(Map<Object, Object> context) {
 
     private static class MapThreadLocal extends ThreadLocal<Map<Object, Object>> {
         protected Map<Object, Object> initialValue() {
-            return new HashMap<Object, Object>() {
+            return new ConcurrentHashMap<Object, Object>() {
 
                 private static final long serialVersionUID = 3637958959138295593L;