RetainFields (Dataflow Library Distribution Project 8.0.0-98 API)

java.lang.Object
- com.pervasive.datarush.operators.AbstractLogicalOperator
- - com.pervasive.datarush.operators.StreamingOperator
  - - com.pervasive.datarush.operators.ExecutableOperator
    - - com.pervasive.datarush.operators.AbstractExecutableRecordPipeline
      - com.pervasive.datarush.operators.record.FilterFields
        
        com.pervasive.datarush.operators.record.RetainFields

All Implemented Interfaces:

LogicalOperator, PipelineOperator<RecordPort>, RecordPipelineOperator
```
public class RetainFields
extends FilterFields
```
Preserves a subset of fields from the input records. Only those fields named in the filter are copied to the output; if a field specified in the filter does not exist in the input, it is ignored. The relative order of fields within the records is unchanged. To require the existence of fields, use SelectFields instead.

See Also:

RemapFields

Field Summary
- Fields inherited from class com.pervasive.datarush.operators.AbstractExecutableRecordPipeline
  input, output

Constructor Summary

Constructors
Constructor Description

RetainFields()
Keeps no fields from the input.

RetainFields(List<String> fields)
Keeps the specified fields from the input.

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method	Description
`RecordPort`	`getInput()`	Gets the record port providing the input data to the operation.
`RecordPort`	`getOutput()`	Gets the record port providing the output from the operation.

Methods inherited from class com.pervasive.datarush.operators.record.FilterFields
computeMetadata, execute, getFieldNames, setFieldNames, setFieldNames

Methods inherited from class com.pervasive.datarush.operators.ExecutableOperator
cloneForExecution, getNumInputCopies, getPortSettings, handleInactiveOutput

Methods inherited from class com.pervasive.datarush.operators.AbstractLogicalOperator
disableParallelism, getInputPorts, getOutputPorts, newInput, newInput, newOutput, newRecordInput, newRecordInput, newRecordOutput, notifyError

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface com.pervasive.datarush.operators.LogicalOperator
disableParallelism, getInputPorts, getOutputPorts

- Constructor Detail
  - RetainFields
```
public RetainFields()
```
    Keeps no fields from the input. To specify fields to keep, use FilterFields.setFieldNames(String...). If no fields are specified when the containing graph is executed, an error will be raised.
  - RetainFields
```
public RetainFields(List<String> fields)
```
    Keeps the specified fields from the input.
    
    Parameters:
    
    fields - the names of fields to keep.
- Method Detail
  - getInput
```
public RecordPort getInput()
```
    Description copied from class: AbstractExecutableRecordPipeline
    
    Gets the record port providing the input data to the operation.
    
    Specified by:
    
    getInput in interface PipelineOperator<RecordPort>
    
    Overrides:
    
    getInput in class AbstractExecutableRecordPipeline
    
    Returns:
    
    the input port for the operation
  - getOutput
```
public RecordPort getOutput()
```
    Description copied from class: AbstractExecutableRecordPipeline
    
    Gets the record port providing the output from the operation.
    
    Specified by:
    
    getOutput in interface PipelineOperator<RecordPort>
    
    Overrides:
    
    getOutput in class AbstractExecutableRecordPipeline
    
    Returns:
    
    the output port for the operation