Java tutorial
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See the License for the * specific language governing permissions and limitations * under the License. */ package org.apache.sysml.runtime.matrix.mapred; import java.io.IOException; import java.util.ArrayList; import java.util.HashMap; import org.apache.hadoop.fs.FileSystem; import org.apache.hadoop.fs.Path; import org.apache.hadoop.io.ByteWritable; import org.apache.hadoop.io.LongWritable; import org.apache.hadoop.io.SequenceFile; import org.apache.hadoop.io.Text; import org.apache.hadoop.io.Writable; import org.apache.hadoop.mapred.JobConf; import org.apache.hadoop.mapred.Mapper; import org.apache.hadoop.mapred.OutputCollector; import org.apache.hadoop.mapred.Reporter; import org.apache.sysml.runtime.instructions.mr.CSVReblockInstruction; import org.apache.sysml.runtime.io.IOUtilFunctions; import org.apache.sysml.runtime.matrix.CSVReblockMR; import org.apache.sysml.runtime.matrix.CSVReblockMR.BlockRow; import org.apache.sysml.runtime.matrix.CSVReblockMR.OffsetCount; import org.apache.sysml.runtime.matrix.data.MatrixBlock; import org.apache.sysml.runtime.matrix.data.TaggedFirstSecondIndexes; import org.apache.sysml.runtime.util.UtilFunctions; public class CSVReblockMapper extends MapperBase implements Mapper<LongWritable, Text, TaggedFirstSecondIndexes, BlockRow> { private long rowOffset = 0; private boolean first = true; private long num = 0; private HashMap<Long, Long> offsetMap = new HashMap<>(); private String _delim = " "; private boolean ignoreFirstLine = false; private boolean headerFile = false; private IndexedBlockRow idxRow = null; public static class IndexedBlockRow { private BlockRow row = null; private TaggedFirstSecondIndexes outIndexes = null; public IndexedBlockRow() { row = new BlockRow(); row.data = new MatrixBlock(); outIndexes = new TaggedFirstSecondIndexes(); } public BlockRow getRow() { return row; } public TaggedFirstSecondIndexes getIndexes() { return outIndexes; } } public static IndexedBlockRow processRow(IndexedBlockRow row, String[] cells, long rowOffset, long num, byte outTag, int brlen, int bclen, boolean fill, double fillValue, OutputCollector<TaggedFirstSecondIndexes, BlockRow> out) throws IOException { int start = 0; row.getIndexes().setTag(outTag); long rowIndex = UtilFunctions.computeBlockIndex(rowOffset + num + 1, brlen); row.getRow().indexInBlock = UtilFunctions.computeCellInBlock(rowOffset + num + 1, brlen); long col = 0; for (; col < cells.length / bclen; col++) { row.getRow().data.reset(1, bclen); row.getIndexes().setIndexes(rowIndex, col + 1); for (int k = 0; k < bclen; k++) { if (cells[k + start] == null || cells[k + start].isEmpty()) { IOUtilFunctions.checkAndRaiseErrorCSVEmptyField(null, fill, true); row.getRow().data.appendValue(0, k, fillValue); } else row.getRow().data.appendValue(0, k, UtilFunctions.parseToDouble(cells[k + start])); } out.collect(row.getIndexes(), row.getRow()); start += bclen; } row.getIndexes().setIndexes(rowIndex, col + 1); int lastBclen = cells.length % bclen; if (lastBclen != 0) { row.getRow().data.reset(1, lastBclen); for (int k = 0; k < lastBclen; k++) { if (cells[k + start] == null || cells[k + start].isEmpty()) { if (!fill) throw new RuntimeException( "Empty fields found in the input delimited file. Use \"fill\" option to read delimited files with empty fields."); row.getRow().data.appendValue(0, k, fillValue); } else row.getRow().data.appendValue(0, k, UtilFunctions.parseToDouble(cells[k + start])); } out.collect(row.getIndexes(), row.getRow()); } return row; } @Override public void map(LongWritable key, Text value, OutputCollector<TaggedFirstSecondIndexes, BlockRow> out, Reporter reporter) throws IOException { if (first) { rowOffset = offsetMap.get(key.get()); first = false; } if (key.get() == 0 && headerFile && ignoreFirstLine) return; String[] cells = IOUtilFunctions.split(value.toString(), _delim); for (int i = 0; i < representativeMatrixes.size(); i++) for (CSVReblockInstruction ins : csv_reblock_instructions.get(i)) { idxRow = processRow(idxRow, cells, rowOffset, num, ins.output, ins.brlen, ins.bclen, ins.fill, ins.fillValue, out); } num++; } @Override @SuppressWarnings("deprecation") public void configure(JobConf job) { super.configure(job); //get the number colums per block //load the offset mapping byte matrixIndex = representativeMatrixes.get(0); try { Path thisPath = new Path(job.get(MRConfigurationNames.MR_MAP_INPUT_FILE)); FileSystem fs = IOUtilFunctions.getFileSystem(thisPath, job); thisPath = thisPath.makeQualified(fs); String filename = thisPath.toString(); Path headerPath = new Path(job.getStrings(CSVReblockMR.SMALLEST_FILE_NAME_PER_INPUT)[matrixIndex]) .makeQualified(fs); if (headerPath.toString().equals(filename)) headerFile = true; ByteWritable key = new ByteWritable(); OffsetCount value = new OffsetCount(); Path p = new Path(job.get(CSVReblockMR.ROWID_FILE_NAME)); SequenceFile.Reader reader = null; try { reader = new SequenceFile.Reader(fs, p, job); while (reader.next(key, value)) { if (key.get() == matrixIndex && filename.equals(value.filename)) offsetMap.put(value.fileOffset, value.count); } } finally { IOUtilFunctions.closeSilently(reader); } } catch (IOException e) { throw new RuntimeException(e); } CSVReblockInstruction ins = csv_reblock_instructions.get(0).get(0); _delim = ins.delim; ignoreFirstLine = ins.hasHeader; idxRow = new IndexedBlockRow(); int maxBclen = 0; for (ArrayList<CSVReblockInstruction> insv : csv_reblock_instructions) for (CSVReblockInstruction in : insv) { if (maxBclen < in.bclen) maxBclen = in.bclen; } //always dense since common csv usecase idxRow.getRow().data.reset(1, maxBclen, false); } @Override protected void specialOperationsForActualMap(int index, OutputCollector<Writable, Writable> out, Reporter reporter) throws IOException { //do nothing } }