Allow rename() to overwrite, fix an uncaught ex and reenable UT

dora/core/client/fs/src/main/java/alluxio/client/file/DoraCacheFileSystem.java

@@ -382,11 +382,12 @@ public void rename(AlluxioURI src, AlluxioURI dst, RenamePOptions options)
     } catch (RuntimeException ex) {
       if (ex instanceof StatusRuntimeException) {
         Status.Code code = ((StatusRuntimeException) ex).getStatus().getCode();
-        if (code == Status.FAILED_PRECONDITION.getCode()) {
-          // throw new RuntimeException(ex.getMessage());
-        } else if (code == Status.NOT_FOUND.getCode()) {
+        if (Status.FAILED_PRECONDITION.getCode().equals(code)) {
+          LOG.error(String.format(
+              "Precondition failed: cannot rename %s to %s", src.toString(), dst.toString()));
+        } else if (Status.NOT_FOUND.getCode().equals(code)) {
           throw new FileNotFoundException(ex.getMessage());
-        } else if (code == Status.ALREADY_EXISTS.getCode()) {
+        } else if (Status.ALREADY_EXISTS.getCode().equals(code)) {
           // throw exception here, no fallback even the fallback is open
           // which means even ufs support overwrite, alluxio won't allow doing it
           throw new FileAlreadyExistsException(ex.getMessage());

dora/core/client/hdfs/src/main/java/alluxio/hadoop/AbstractFileSystem.java

@@ -699,7 +699,7 @@ public boolean rename(Path src, Path dst) throws IOException {
     if (mStatistics != null) {
       mStatistics.incrementWriteOps(1);
     }
-    if (src == dst) {
+    if (src.equals(dst)) {
       LOG.debug("Renaming {} to the same location", src);
       return true;
     }
@@ -720,25 +720,26 @@ public boolean rename(Path src, Path dst) throws IOException {
       try {
         boolean res = tryMoveIntoDirectory(src, dst, srcPath, dstPath);
         if (!res) {
-          LOG.warn("Failed to rename file and dst {} is not a directory", dst, exToLog);
+          LOG.warn("Failed to rename src {} to dst {}"
+              + "because the dst is not a directory", src,  dst, exToLog);
         }
       } catch (IOException | AlluxioException | AlluxioRuntimeException e2) {
-        LOG.error("Failed to rename file {} and failed to move into dst directory {}",
+        LOG.error("Failed to rename src {} to dst {} with exception {},"
+                + "and fail to move src to dst as a folder with exception",
             src, dst, exToLog, e2);
         return false;
       }
-    } catch (IOException e) {
+    } catch (IOException | RuntimeException e) {
       LOG.error("Failed to rename {} to {}", src, dst, e);
       return false;
-    } catch (RuntimeException e) {
-      return false;
     }
     return true;
   }
 
   /**
    * rename when previous rename fail, reconstruct path and check status.
    * In order to support hdfs rename interface
+   *
    * @param src src
    * @param dst dst
    * @param srcPath srcPath

dora/tests/integration/src/test/java/alluxio/client/hadoop/FileSystemRenameIntegrationTest.java

@@ -48,7 +48,6 @@ public final class FileSystemRenameIntegrationTest extends BaseIntegrationTest {
           .setProperty(PropertyKey.USER_FILE_WRITE_TYPE_DEFAULT, WriteType.CACHE_THROUGH)
           .setProperty(PropertyKey.UNDERFS_XATTR_CHANGE_ENABLED, false)
           .setProperty(PropertyKey.USER_FILE_METADATA_SYNC_INTERVAL, 0)
-          .setProperty(PropertyKey.USER_FILE_METADATA_SYNC_INTERVAL, 0)
           .setProperty(PropertyKey.DORA_WORKER_METASTORE_ROCKSDB_TTL, 0)
           .setProperty(PropertyKey.DORA_UFS_LIST_STATUS_CACHE_TTL, 0)
           .setProperty(PropertyKey.DORA_CLIENT_UFS_FALLBACK_ENABLED, false)