org.apache.hadoop.hive.ql.udf.ptf

Class MatchPath

java.lang.Object

org.apache.hadoop.hive.ql.udf.ptf.TableFunctionEvaluator

org.apache.hadoop.hive.ql.udf.ptf.MatchPath

public class MatchPath
extends TableFunctionEvaluator

return rows that meet a specified pattern. Use symbols to specify a list of expressions to match. Pattern is used to specify a Path. The results list can contain expressions based on the input columns and also the matched Path.

1. pattern: pattern for the Path. Path is 'dot' separated list of symbols. Each element is treated as a symbol. Elements that end in '*' or '+' are interpreted with the usual meaning of zero or more, one or more respectively. For e.g. "LATE.EARLY*.ONTIMEOREARLY" implies a sequence of flights where the first occurrence was LATE, followed by zero or more EARLY flights, followed by a ONTIME or EARLY flight.
2. symbols specify a list of name, expression pairs. For e.g. 'LATE', arrival_delay > 0, 'EARLY', arrival_delay < 0 , 'ONTIME', arrival_delay == 0. These symbols can be used in the Pattern defined above.
3. resultSelectList specified as a select list. The expressions in the selectList are evaluated in the context where all the input columns are available, plus the attribute "tpath" is available. Path is a collection of rows that represents the matching Path.

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	MatchPath.Chain
static class	MatchPath.MatchPathResolver
static class	MatchPath.Plus
static class	MatchPath.ResultExpressionParser
static class	MatchPath.ResultExprInfo
static class	MatchPath.Star
static class	MatchPath.Symbol
static class	MatchPath.SymbolFunction
static class	MatchPath.SymbolFunctionResult
static class	MatchPath.SymbolParser

Field Summary

Fields

Modifier and Type	Field and Description
static String	PATHATTR_NAME

Fields inherited from class org.apache.hadoop.hive.ql.udf.ptf.TableFunctionEvaluator

canAcceptInputAsStream, OI, outputPartition, ptfDesc, rawInputOI, tableDef

Constructor Summary

Constructors

Constructor and Description
MatchPath()

Method Summary

Modifier and Type	Method and Description
protected static StructObjectInspector	createSelectListOI(MatchPath evaluator, PTFInputDef inpDef)
protected static RowResolver	createSelectListRR(MatchPath evaluator, PTFInputDef inpDef)
void	execute(PTFPartition.PTFPartitionIterator<Object> pItr, PTFPartition outP)
HashMap<String,String>	getInputColumnNames()
static ArrayList<Object>	getPath(Object currRow, ObjectInspector rowOI, PTFPartition.PTFPartitionIterator<Object> pItr, int sz)
MatchPath.ResultExprInfo	getResultExprInfo()
static Object	getSelectListInput(Object currRow, ObjectInspector rowOI, PTFPartition.PTFPartitionIterator<Object> pItr, int sz)
void	setInputColumnNames(HashMap<String,String> inputColumnNamesMap)
void	setResultExprInfo(MatchPath.ResultExprInfo resultExprInfo)

Methods inherited from class org.apache.hadoop.hive.ql.udf.ptf.TableFunctionEvaluator

_transformRawInput, canAcceptInputAsStream, canIterateOutput, close, execute, finishPartition, getOutputOI, getQueryDef, getRawInputOI, getTableDef, initializeStreaming, isTransformsRawInput, iterator, processRow, setOutputOI, setQueryDef, setRawInputOI, setTableDef, setTransformsRawInput, startPartition, transformRawInput, transformRawInputIterator

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

PATHATTR_NAME

public static final String PATHATTR_NAME

See Also:

Constant Field Values

Constructor Detail

MatchPath

public MatchPath()

Method Detail

execute

public void execute(PTFPartition.PTFPartitionIterator<Object> pItr,
                    PTFPartition outP)
             throws HiveException

Specified by:

execute in class TableFunctionEvaluator

Throws:

HiveException

getInputColumnNames

public HashMap<String,String> getInputColumnNames()

setInputColumnNames

public void setInputColumnNames(HashMap<String,String> inputColumnNamesMap)

getResultExprInfo

public MatchPath.ResultExprInfo getResultExprInfo()

setResultExprInfo

public void setResultExprInfo(MatchPath.ResultExprInfo resultExprInfo)

createSelectListRR

protected static RowResolver createSelectListRR(MatchPath evaluator,
                                                PTFInputDef inpDef)
                                         throws SemanticException

Throws:

SemanticException

createSelectListOI

protected static StructObjectInspector createSelectListOI(MatchPath evaluator,
                                                          PTFInputDef inpDef)

getSelectListInput

public static Object getSelectListInput(Object currRow,
                                        ObjectInspector rowOI,
                                        PTFPartition.PTFPartitionIterator<Object> pItr,
                                        int sz)
                                 throws HiveException

Throws:

HiveException

getPath

public static ArrayList<Object> getPath(Object currRow,
                                        ObjectInspector rowOI,
                                        PTFPartition.PTFPartitionIterator<Object> pItr,
                                        int sz)
                                 throws HiveException

Throws:

HiveException