fix dr nullptr

Author: maochongxin

src/main/java/com/alipay/oceanbase/rpc/ObTableClient.java

@@ -1664,7 +1664,10 @@ private ObPair<Long, ReplicaLocation> getPartitionReplica(TableEntry tableEntry,
      */
     private ReplicaLocation getPartitionLocation(TableEntry tableEntry, long partId,
                                                  ObServerRoute route) {
-        return tableEntry.getPartitionEntry().getPartitionLocationWithPartId(partId)
+        // In all cases for 3.x and for non-partitioned tables in 4.x, partId will not change.
+        // If it is 4.x, it will be converted to tablet id. 
+        partId = getTabletIdByPartId(tableEntry, partId);
+        return tableEntry.getPartitionEntry().getPartitionLocationWithTabletId(partId)
             .getReplica(route);
 
     }

src/main/java/com/alipay/oceanbase/rpc/location/model/partition/ObPartitionEntry.java

@@ -67,18 +67,18 @@ public ObPartitionLocation getPartitionLocationWithPartId(long partId) {
     }
 
     /*
-     * Put partition location with part id.
+     * Get partition location with tablet id.
      */
-    public ObPartitionLocation putPartitionLocationWithPartId(long partId,
-                                                              ObPartitionLocation ObpartitionLocation) {
-        return partitionLocation.put(partId, ObpartitionLocation);
+    public ObPartitionLocation getPartitionLocationWithTabletId(long tabletId) {
+        return partitionLocation.get(tabletId);
     }
 
     /*
-     * Get partition location with tablet id.
+     * Put partition location with part id.
      */
-    public ObPartitionLocation getPartitionLocationWithTabletId(long tabletId) {
-        return partitionLocation.get(tabletId);
+    public ObPartitionLocation putPartitionLocationWithPartId(long partId,
+                                                              ObPartitionLocation ObpartitionLocation) {
+        return partitionLocation.put(partId, ObpartitionLocation);
     }
 
     /*