org.apache.pig.piggybank.evaluation.string
Class LOWER
java.lang.Object
org.apache.pig.EvalFunc<String>
org.apache.pig.piggybank.evaluation.string.LOWER
Deprecated. Use LOWER
@Deprecated
public class LOWER
- extends EvalFunc<String>
Constructor Summary |
LOWER()
Deprecated. |
Methods inherited from class org.apache.pig.EvalFunc |
finish, getCacheFiles, getLogger, getPigLogger, getReporter, getReturnType, getSchemaName, isAsynchronous, progress, setPigLogger, setReporter, warn |
Methods inherited from class java.lang.Object |
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait |
LOWER
public LOWER()
- Deprecated.
exec
public String exec(Tuple input)
throws IOException
- Deprecated.
- Method invoked on every tuple during foreach evaluation
- Specified by:
exec
in class EvalFunc<String>
- Parameters:
input
- tuple; first column is assumed to have the column to convert
- Returns:
- result, of type T.
- Throws:
IOException
outputSchema
public Schema outputSchema(Schema input)
- Deprecated.
- This method gives a name to the column.
- Overrides:
outputSchema
in class EvalFunc<String>
- Parameters:
input
- - schema of the input data
- Returns:
- schema of the input data
getArgToFuncMapping
public List<FuncSpec> getArgToFuncMapping()
throws FrontendException
- Deprecated.
- Description copied from class:
EvalFunc
- Allow a UDF to specify type specific implementations of itself. For example,
an implementation of arithmetic sum might have int and float implementations,
since integer arithmetic performs much better than floating point arithmetic. Pig's
typechecker will call this method and using the returned list plus the schema
of the function's input data, decide which implementation of the UDF to use.
- Overrides:
getArgToFuncMapping
in class EvalFunc<String>
- Returns:
- A List containing FuncSpec objects representing the EvalFunc class
which can handle the inputs corresponding to the schema in the objects. Each
FuncSpec should be constructed with a schema that describes the input for that
implementation. For example, the sum function above would return two elements in its
list:
- FuncSpec(this.getClass().getName(), new Schema(new Schema.FieldSchema(null, DataType.DOUBLE)))
- FuncSpec(IntSum.getClass().getName(), new Schema(new Schema.FieldSchema(null, DataType.INTEGER)))
This would indicate that the main implementation is used for doubles, and the special
implementation IntSum is used for ints.
- Throws:
FrontendException
Copyright © 2012 The Apache Software Foundation