Examples with ByteArrayComparable org.apache.hadoop.hbase.filter.ByteArrayComparable used on opensource projects

Example 11 with ByteArrayComparable

use of org.apache.hadoop.hbase.filter.ByteArrayComparable in project drill by apache.

the class MapRDBFilterBuilder method createHBaseScanSpec.

private HBaseScanSpec createHBaseScanSpec(FunctionCall call, MaprDBCompareFunctionsProcessor processor) {
    String functionName = processor.getFunctionName();
    SchemaPath field = processor.getPath();
    byte[] fieldValue = processor.getValue();
    boolean sortOrderAscending = processor.isSortOrderAscending();
    boolean isRowKey = field.getRootSegmentPath().equals(ROW_KEY);
    if (!(isRowKey || (!field.getRootSegment().isLastPath() && field.getRootSegment().getChild().isLastPath() && field.getRootSegment().getChild().isNamed()))) {
        /*
       * if the field in this function is neither the row_key nor a qualified HBase column, return.
       */
        return null;
    }
    if (processor.isRowKeyPrefixComparison()) {
        return createRowKeyPrefixScanSpec(call, processor);
    }
    CompareOp compareOp = null;
    boolean isNullTest = false;
    ByteArrayComparable comparator = new BinaryComparator(fieldValue);
    byte[] startRow = HConstants.EMPTY_START_ROW;
    byte[] stopRow = HConstants.EMPTY_END_ROW;
    switch(functionName) {
        case FunctionNames.EQ:
            compareOp = CompareOp.EQUAL;
            if (isRowKey) {
                startRow = fieldValue;
                /* stopRow should be just greater than 'value'*/
                stopRow = Arrays.copyOf(fieldValue, fieldValue.length + 1);
                compareOp = CompareOp.EQUAL;
            }
            break;
        case FunctionNames.NE:
            compareOp = CompareOp.NOT_EQUAL;
            break;
        case FunctionNames.GE:
            if (sortOrderAscending) {
                compareOp = CompareOp.GREATER_OR_EQUAL;
                if (isRowKey) {
                    startRow = fieldValue;
                }
            } else {
                compareOp = CompareOp.LESS_OR_EQUAL;
                if (isRowKey) {
                    // stopRow should be just greater than 'value'
                    stopRow = Arrays.copyOf(fieldValue, fieldValue.length + 1);
                }
            }
            break;
        case FunctionNames.GT:
            if (sortOrderAscending) {
                compareOp = CompareOp.GREATER;
                if (isRowKey) {
                    // startRow should be just greater than 'value'
                    startRow = Arrays.copyOf(fieldValue, fieldValue.length + 1);
                }
            } else {
                compareOp = CompareOp.LESS;
                if (isRowKey) {
                    stopRow = fieldValue;
                }
            }
            break;
        case FunctionNames.LE:
            if (sortOrderAscending) {
                compareOp = CompareOp.LESS_OR_EQUAL;
                if (isRowKey) {
                    // stopRow should be just greater than 'value'
                    stopRow = Arrays.copyOf(fieldValue, fieldValue.length + 1);
                }
            } else {
                compareOp = CompareOp.GREATER_OR_EQUAL;
                if (isRowKey) {
                    startRow = fieldValue;
                }
            }
            break;
        case FunctionNames.LT:
            if (sortOrderAscending) {
                compareOp = CompareOp.LESS;
                if (isRowKey) {
                    stopRow = fieldValue;
                }
            } else {
                compareOp = CompareOp.GREATER;
                if (isRowKey) {
                    // startRow should be just greater than 'value'
                    startRow = Arrays.copyOf(fieldValue, fieldValue.length + 1);
                }
            }
            break;
        case FunctionNames.IS_NULL:
        case "isNull":
        case "is null":
            if (isRowKey) {
                return null;
            }
            isNullTest = true;
            compareOp = CompareOp.EQUAL;
            comparator = new NullComparator();
            break;
        case FunctionNames.IS_NOT_NULL:
        case "isNotNull":
        case "is not null":
            if (isRowKey) {
                return null;
            }
            compareOp = CompareOp.NOT_EQUAL;
            comparator = new NullComparator();
            break;
        case "like":
            /*
       * Convert the LIKE operand to Regular Expression pattern so that we can
       * apply RegexStringComparator()
       */
            HBaseRegexParser parser = new HBaseRegexParser(call).parse();
            compareOp = CompareOp.EQUAL;
            comparator = new RegexStringComparator(parser.getRegexString());
            /*
       * We can possibly do better if the LIKE operator is on the row_key
       */
            if (isRowKey) {
                String prefix = parser.getPrefixString();
                if (prefix != null) {
                    /*
           * If there is a literal prefix, it can help us prune the scan to a sub range
           */
                    if (prefix.equals(parser.getLikeString())) {
                        /* The operand value is literal. This turns the LIKE operator to EQUAL operator */
                        startRow = stopRow = fieldValue;
                        compareOp = null;
                    } else {
                        startRow = prefix.getBytes(Charsets.UTF_8);
                        stopRow = startRow.clone();
                        boolean isMaxVal = true;
                        for (int i = stopRow.length - 1; i >= 0; --i) {
                            int nextByteValue = (0xff & stopRow[i]) + 1;
                            if (nextByteValue < 0xff) {
                                stopRow[i] = (byte) nextByteValue;
                                isMaxVal = false;
                                break;
                            } else {
                                stopRow[i] = 0;
                            }
                        }
                        if (isMaxVal) {
                            stopRow = HConstants.EMPTY_END_ROW;
                        }
                    }
                }
            }
            break;
    }
    if (compareOp != null || startRow != HConstants.EMPTY_START_ROW || stopRow != HConstants.EMPTY_END_ROW) {
        Filter filter = null;
        if (isRowKey) {
            if (compareOp != null) {
                filter = new RowFilter(compareOp, comparator);
            }
        } else {
            byte[] family = HBaseUtils.getBytes(field.getRootSegment().getPath());
            byte[] qualifier = HBaseUtils.getBytes(field.getRootSegment().getChild().getNameSegment().getPath());
            filter = new SingleColumnValueFilter(family, qualifier, compareOp, comparator);
            ((SingleColumnValueFilter) filter).setLatestVersionOnly(true);
            if (!isNullTest) {
                ((SingleColumnValueFilter) filter).setFilterIfMissing(true);
            }
        }
        return new HBaseScanSpec(groupScan.getTableName(), startRow, stopRow, filter);
    }
    // else
    return null;
}