CountAggregate

java.lang.Object
- org.apache.iceberg.expressions.Aggregate<BoundTerm<T>>
- - org.apache.iceberg.expressions.BoundAggregate<T,java.lang.Long>
  - - org.apache.iceberg.expressions.CountAggregate<T>

All Implemented Interfaces:

java.io.Serializable, Bound<java.lang.Long>, Expression

Direct Known Subclasses:

CountNonNull, CountStar
```
public class CountAggregate<T>
extends BoundAggregate<T,java.lang.Long>
```
See Also:

Serialized Form

Nested Class Summary
- Nested classes/interfaces inherited from interface org.apache.iceberg.expressions.Expression
  Expression.Operation

Constructor Summary

Constructors
Modifier Constructor Description

protected CountAggregate(Expression.Operation op, BoundTerm<T> term)

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method	Description
`protected java.lang.Long`	`countFor(DataFile file)`
`protected java.lang.Long`	`countFor(StructLike row)`
`java.lang.Long`	`eval(DataFile file)`
`java.lang.Long`	`eval(StructLike struct)`	Produce a value from the struct for this expression.
`org.apache.iceberg.expressions.BoundAggregate.Aggregator<java.lang.Long>`	`newAggregator()`

Methods inherited from class org.apache.iceberg.expressions.BoundAggregate
columnName, describe, ref, type

Methods inherited from class org.apache.iceberg.expressions.Aggregate
op, term, toString

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

Methods inherited from interface org.apache.iceberg.expressions.Expression
isEquivalentTo, negate

Constructor Detail

CountAggregate

protected CountAggregate(Expression.Operation op,
                         BoundTerm<T> term)

Method Detail
- eval
```
public java.lang.Long eval(StructLike struct)
```
  Description copied from interface: Bound
  
  Produce a value from the struct for this expression.
  
  Specified by:
  
  eval in interface Bound<T>
  
  Overrides:
  
  eval in class BoundAggregate<T,java.lang.Long>
  
  Parameters:
  
  struct - a struct of incoming data
  
  Returns:
  
  the value of this expression when evaluated on the incoming struct
- eval
```
public java.lang.Long eval(DataFile file)
```
- countFor
```
protected java.lang.Long countFor(StructLike row)
```
- countFor
```
protected java.lang.Long countFor(DataFile file)
```
- newAggregator
```
public org.apache.iceberg.expressions.BoundAggregate.Aggregator<java.lang.Long> newAggregator()
```