/**
* Method to merge multiple CSV part files on HDFS into a single CSV file on HDFS. The part files
* are created by CSV_WRITE MR job.
*
* <p>This method is invoked from CP-write instruction.
*
* @param srcFileName
* @param destFileName
* @param csvprop
* @param rlen
* @param clen
* @throws IOException
*/
public final void mergeCSVPartFiles(
String srcFileName,
String destFileName,
CSVFileFormatProperties csvprop,
long rlen,
long clen)
throws IOException {
Configuration conf = new Configuration(ConfigurationManager.getCachedJobConf());
Path srcFilePath = new Path(srcFileName);
Path mergedFilePath = new Path(destFileName);
FileSystem hdfs = FileSystem.get(conf);
if (hdfs.exists(mergedFilePath)) {
hdfs.delete(mergedFilePath, true);
}
OutputStream out = hdfs.create(mergedFilePath, true);
// write out the header, if needed
if (csvprop.hasHeader()) {
StringBuilder sb = new StringBuilder();
for (int i = 0; i < clen; i++) {
sb.append("C" + (i + 1));
if (i < clen - 1) sb.append(csvprop.getDelim());
}
sb.append('\n');
out.write(sb.toString().getBytes());
sb.setLength(0);
}
// if the source is a directory
if (hdfs.isDirectory(srcFilePath)) {
try {
FileStatus[] contents = hdfs.listStatus(srcFilePath);
Path[] partPaths = new Path[contents.length];
int numPartFiles = 0;
for (int i = 0; i < contents.length; i++) {
if (!contents[i].isDirectory()) {
partPaths[i] = contents[i].getPath();
numPartFiles++;
}
}
Arrays.sort(partPaths);
for (int i = 0; i < numPartFiles; i++) {
InputStream in = hdfs.open(partPaths[i]);
try {
IOUtils.copyBytes(in, out, conf, false);
if (i < numPartFiles - 1) out.write('\n');
} finally {
IOUtilFunctions.closeSilently(in);
}
}
} finally {
IOUtilFunctions.closeSilently(out);
}
} else if (hdfs.isFile(srcFilePath)) {
InputStream in = null;
try {
in = hdfs.open(srcFilePath);
IOUtils.copyBytes(in, out, conf, true);
} finally {
IOUtilFunctions.closeSilently(in);
IOUtilFunctions.closeSilently(out);
}
} else {
throw new IOException(srcFilePath.toString() + ": No such file or directory");
}
}
/**
* @param srcFileName
* @param destFileName
* @param csvprop
* @param rlen
* @param clen
* @throws IOException
*/
@SuppressWarnings("unchecked")
public final void addHeaderToCSV(String srcFileName, String destFileName, long rlen, long clen)
throws IOException {
Configuration conf = new Configuration(ConfigurationManager.getCachedJobConf());
Path srcFilePath = new Path(srcFileName);
Path destFilePath = new Path(destFileName);
FileSystem hdfs = FileSystem.get(conf);
if (!_props.hasHeader()) {
// simply move srcFile to destFile
/*
* TODO: Remove this roundabout way!
* For example: destFilePath = /user/biadmin/csv/temp/out/file.csv
* & the only path that exists already on HDFS is /user/biadmin/csv/.
* In this case: the directory structure /user/biadmin/csv/temp/out must be created.
* Simple hdfs.rename() does not seem to create this directory structure.
*/
// delete the destination file, if exists already
// boolean ret1 =
hdfs.delete(destFilePath, true);
// Create /user/biadmin/csv/temp/out/file.csv so that ..../temp/out/ is created.
// boolean ret2 =
hdfs.createNewFile(destFilePath);
// delete the file "file.csv" but preserve the directory structure /user/biadmin/csv/temp/out/
// boolean ret3 =
hdfs.delete(destFilePath, true);
// finally, move the data to destFilePath = /user/biadmin/csv/temp/out/file.csv
// boolean ret4 =
hdfs.rename(srcFilePath, destFilePath);
// System.out.println("Return values = del:" + ret1 + ", createNew:" + ret2 + ", del:" + ret3
// + ", rename:" + ret4);
return;
}
// construct the header line
StringBuilder sb = new StringBuilder();
for (int i = 0; i < clen; i++) {
sb.append("C" + (i + 1));
if (i < clen - 1) sb.append(_props.getDelim());
}
sb.append('\n');
if (hdfs.isDirectory(srcFilePath)) {
// compute sorted order among part files
ArrayList<Path> files = new ArrayList<Path>();
for (FileStatus stat : hdfs.listStatus(srcFilePath, CSVReblockMR.hiddenFileFilter))
files.add(stat.getPath());
Collections.sort(files);
// first part file path
Path firstpart = files.get(0);
// create a temp file, and add header and contents of first part
Path tmp = new Path(firstpart.toString() + ".tmp");
OutputStream out = hdfs.create(tmp, true);
out.write(sb.toString().getBytes());
sb.setLength(0);
// copy rest of the data from firstpart
InputStream in = null;
try {
in = hdfs.open(firstpart);
IOUtils.copyBytes(in, out, conf, true);
} finally {
IOUtilFunctions.closeSilently(in);
IOUtilFunctions.closeSilently(out);
}
// rename tmp to firstpart
hdfs.delete(firstpart, true);
hdfs.rename(tmp, firstpart);
// rename srcfile to destFile
hdfs.delete(destFilePath, true);
hdfs.createNewFile(destFilePath); // force the creation of directory structure
hdfs.delete(destFilePath, true); // delete the file, but preserve the directory structure
hdfs.rename(srcFilePath, destFilePath); // move the data
} else if (hdfs.isFile(srcFilePath)) {
// create destination file
OutputStream out = hdfs.create(destFilePath, true);
// write header
out.write(sb.toString().getBytes());
sb.setLength(0);
// copy the data from srcFile
InputStream in = null;
try {
in = hdfs.open(srcFilePath);
IOUtils.copyBytes(in, out, conf, true);
} finally {
IOUtilFunctions.closeSilently(in);
IOUtilFunctions.closeSilently(out);
}
} else {
throw new IOException(srcFilePath.toString() + ": No such file or directory");
}
}
/**
* @param fileName
* @param src
* @param rlen
* @param clen
* @param nnz
* @throws IOException
*/
protected final void writeCSVMatrixToFile(
Path path,
JobConf job,
FileSystem fs,
MatrixBlock src,
int rl,
int ru,
CSVFileFormatProperties props)
throws IOException {
boolean sparse = src.isInSparseFormat();
int clen = src.getNumColumns();
// create buffered writer
BufferedWriter br = new BufferedWriter(new OutputStreamWriter(fs.create(path, true)));
try {
// for obj reuse and preventing repeated buffer re-allocations
StringBuilder sb = new StringBuilder();
props = (props == null) ? new CSVFileFormatProperties() : props;
String delim = props.getDelim();
boolean csvsparse = props.isSparse();
// Write header line, if needed
if (props.hasHeader() && rl == 0) {
// write row chunk-wise to prevent OOM on large number of columns
for (int bj = 0; bj < clen; bj += BLOCKSIZE_J) {
for (int j = bj; j < Math.min(clen, bj + BLOCKSIZE_J); j++) {
sb.append("C" + (j + 1));
if (j < clen - 1) sb.append(delim);
}
br.write(sb.toString());
sb.setLength(0);
}
sb.append('\n');
br.write(sb.toString());
sb.setLength(0);
}
// Write data lines
if (sparse) // SPARSE
{
SparseBlock sblock = src.getSparseBlock();
for (int i = rl; i < ru; i++) {
// write row chunk-wise to prevent OOM on large number of columns
int prev_jix = -1;
if (sblock != null && i < sblock.numRows() && !sblock.isEmpty(i)) {
int pos = sblock.pos(i);
int alen = sblock.size(i);
int[] aix = sblock.indexes(i);
double[] avals = sblock.values(i);
for (int j = pos; j < pos + alen; j++) {
int jix = aix[j];
// output empty fields, if needed
for (int j2 = prev_jix; j2 < jix - 1; j2++) {
if (!csvsparse) sb.append('0');
sb.append(delim);
// flush buffered string
if (j2 % BLOCKSIZE_J == 0) {
br.write(sb.toString());
sb.setLength(0);
}
}
// output the value (non-zero)
sb.append(avals[j]);
if (jix < clen - 1) sb.append(delim);
br.write(sb.toString());
sb.setLength(0);
// flush buffered string
if (jix % BLOCKSIZE_J == 0) {
br.write(sb.toString());
sb.setLength(0);
}
prev_jix = jix;
}
}
// Output empty fields at the end of the row.
// In case of an empty row, output (clen-1) empty fields
for (int bj = prev_jix + 1; bj < clen; bj += BLOCKSIZE_J) {
for (int j = bj; j < Math.min(clen, bj + BLOCKSIZE_J); j++) {
if (!csvsparse) sb.append('0');
if (j < clen - 1) sb.append(delim);
}
br.write(sb.toString());
sb.setLength(0);
}
sb.append('\n');
br.write(sb.toString());
sb.setLength(0);
}
} else // DENSE
{
for (int i = rl; i < ru; i++) {
// write row chunk-wise to prevent OOM on large number of columns
for (int bj = 0; bj < clen; bj += BLOCKSIZE_J) {
for (int j = bj; j < Math.min(clen, bj + BLOCKSIZE_J); j++) {
double lvalue = src.getValueDenseUnsafe(i, j);
if (lvalue != 0) // for nnz
sb.append(lvalue);
else if (!csvsparse) sb.append('0');
if (j != clen - 1) sb.append(delim);
}
br.write(sb.toString());
sb.setLength(0);
}
sb.append('\n');
br.write(sb.toString()); // same as append
sb.setLength(0);
}
}
} finally {
IOUtilFunctions.closeSilently(br);
}
}