Github user zzcclp commented on a diff in the pull request:
https://github.com/apache/carbondata/pull/1516#discussion_r151633344
--- Diff:
core/src/main/java/org/apache/carbondata/core/datastore/filesystem/AbstractDFSCarbonFile.java
---
@@ -154,52 +155,68 @@ public boolean delete() {
* This method will delete the data in file data from a given offset
*/
@Override public boolean truncate(String fileName, long
validDataEndOffset) {
- DataOutputStream dataOutputStream = null;
- DataInputStream dataInputStream = null;
boolean fileTruncatedSuccessfully = false;
- // if bytes to read less than 1024 then buffer size should be equal to
the given offset
- int bufferSize = validDataEndOffset >
CarbonCommonConstants.BYTE_TO_KB_CONVERSION_FACTOR ?
- CarbonCommonConstants.BYTE_TO_KB_CONVERSION_FACTOR :
- (int) validDataEndOffset;
- // temporary file name
- String tempWriteFilePath = fileName +
CarbonCommonConstants.TEMPWRITEFILEEXTENSION;
- FileFactory.FileType fileType = FileFactory.getFileType(fileName);
try {
- CarbonFile tempFile;
- // delete temporary file if it already exists at a given path
- if (FileFactory.isFileExist(tempWriteFilePath, fileType)) {
- tempFile = FileFactory.getCarbonFile(tempWriteFilePath, fileType);
- tempFile.delete();
- }
- // create new temporary file
- FileFactory.createNewFile(tempWriteFilePath, fileType);
- tempFile = FileFactory.getCarbonFile(tempWriteFilePath, fileType);
- byte[] buff = new byte[bufferSize];
- dataInputStream = FileFactory.getDataInputStream(fileName, fileType);
- // read the data
- int read = dataInputStream.read(buff, 0, buff.length);
- dataOutputStream =
FileFactory.getDataOutputStream(tempWriteFilePath, fileType);
- dataOutputStream.write(buff, 0, read);
- long remaining = validDataEndOffset - read;
- // anytime we should not cross the offset to be read
- while (remaining > 0) {
- if (remaining > bufferSize) {
- buff = new byte[bufferSize];
- } else {
- buff = new byte[(int) remaining];
+ // if hadoop version >= 2.7, it can call method 'truncate' to
truncate file,
+ // this method was new in hadoop 2.7
+ FileSystem fs =
fileStatus.getPath().getFileSystem(FileFactory.getConfiguration());
+ Method truncateMethod = fs.getClass().getDeclaredMethod("truncate",
+ new Class[]{Path.class, long.class});
+ fileTruncatedSuccessfully = (boolean)truncateMethod.invoke(fs,
+ new Object[]{fileStatus.getPath(), validDataEndOffset});
+ } catch (NoSuchMethodException e) {
+ LOGGER.error("there is no 'truncate' method in FileSystem, the
version of hadoop is"
+ + " below 2.7, It needs to implement truncate file by other
way.");
+ DataOutputStream dataOutputStream = null;
+ DataInputStream dataInputStream = null;
+ // if bytes to read less than 1024 then buffer size should be equal
to the given offset
+ int bufferSize = validDataEndOffset >
CarbonCommonConstants.BYTE_TO_KB_CONVERSION_FACTOR ?
+ CarbonCommonConstants.BYTE_TO_KB_CONVERSION_FACTOR :
+ (int) validDataEndOffset;
+ // temporary file name
+ String tempWriteFilePath = fileName +
CarbonCommonConstants.TEMPWRITEFILEEXTENSION;
+ FileFactory.FileType fileType = FileFactory.getFileType(fileName);
+ try {
+ CarbonFile tempFile;
+ // delete temporary file if it already exists at a given path
+ if (FileFactory.isFileExist(tempWriteFilePath, fileType)) {
+ tempFile = FileFactory.getCarbonFile(tempWriteFilePath,
fileType);
+ tempFile.delete();
}
- read = dataInputStream.read(buff, 0, buff.length);
+ // create new temporary file
+ FileFactory.createNewFile(tempWriteFilePath, fileType);
+ tempFile = FileFactory.getCarbonFile(tempWriteFilePath, fileType);
+ byte[] buff = new byte[bufferSize];
+ dataInputStream = FileFactory.getDataInputStream(fileName,
fileType);
+ // read the data
+ int read = dataInputStream.read(buff, 0, buff.length);
+ dataOutputStream =
FileFactory.getDataOutputStream(tempWriteFilePath, fileType);
dataOutputStream.write(buff, 0, read);
- remaining = remaining - read;
+ long remaining = validDataEndOffset - read;
+ // anytime we should not cross the offset to be read
+ while (remaining > 0) {
+ if (remaining > bufferSize) {
+ buff = new byte[bufferSize];
+ } else {
+ buff = new byte[(int) remaining];
+ }
+ read = dataInputStream.read(buff, 0, buff.length);
+ dataOutputStream.write(buff, 0, read);
+ remaining = remaining - read;
+ }
+ CarbonUtil.closeStreams(dataInputStream, dataOutputStream);
+ // rename the temp file to original file
+ tempFile.renameForce(fileName);
+ fileTruncatedSuccessfully = true;
+ } catch (IOException ioe) {
+ LOGGER.error("IOException occurred while truncating the file " +
ioe.getMessage());
+ } finally {
+ CarbonUtil.closeStreams(dataOutputStream, dataInputStream);
}
- CarbonUtil.closeStreams(dataInputStream, dataOutputStream);
- // rename the temp file to original file
- tempFile.renameForce(fileName);
- fileTruncatedSuccessfully = true;
} catch (IOException e) {
- LOGGER.error("Exception occurred while truncating the file " +
e.getMessage());
- } finally {
- CarbonUtil.closeStreams(dataOutputStream, dataInputStream);
+ LOGGER.error("IOException occurred while truncating the file " +
e.getMessage());
+ } catch (Exception e) {
--- End diff --
Method.invoke may throw other exceptions when running, such as:
IllegalAccessException,
IllegalArgumentException, InvocationTargetException;
So need to add this catch for above exceptions.
The finally block is for the try block which is in catch
NoSuchMethodException branch.
---
