io.delta.kernel.expressions

Class Column

java.lang.Object

io.delta.kernel.expressions.LeafExpression

io.delta.kernel.expressions.Column

All Implemented Interfaces:

Expression

public final class Column
extends LeafExpression

A column whose row-value will be computed based on the data in a Row.

It is recommended that you instantiate using an existing table schema StructType with StructType.column(int).

Only supports primitive data types, see Delta Transaction Log Protocol: Primitive Types.

Constructor Summary

Constructors

Constructor and Description
Column(int ordinal, java.lang.String name, DataType dataType)

Method Summary

Modifier and Type	Method and Description
DataType	dataType()
boolean	equals(java.lang.Object o)
java.lang.Object	eval(Row row)
int	hashCode()
java.lang.String	name()
java.util.Set<java.lang.String>	references()
java.lang.String	toString()

Methods inherited from class io.delta.kernel.expressions.LeafExpression

children

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Constructor Detail

Column

public Column(int ordinal,
              java.lang.String name,
              DataType dataType)

Method Detail

name

public java.lang.String name()

eval

public java.lang.Object eval(Row row)

Parameters:

row - the input row to evaluate.

Returns:

the result of evaluating this expression on the given input Row.

dataType

public DataType dataType()

Returns:

the DataType of the result of evaluating this expression.

toString

public java.lang.String toString()

Specified by:

toString in interface Expression

Overrides:

toString in class java.lang.Object

Returns:

the String representation of this expression.

references

public java.util.Set<java.lang.String> references()

Specified by:

references in interface Expression

Overrides:

references in class LeafExpression

Returns:

the names of columns referenced by this expression.

equals

public boolean equals(java.lang.Object o)

Specified by:

equals in class LeafExpression

hashCode

public int hashCode()

Specified by:

hashCode in class LeafExpression