io.cdap.wrangler.api.lineage

Class Many

java.lang.Object

io.cdap.wrangler.api.lineage.Many

All Implemented Interfaces:

Serializable

@Beta
public final class Many
extends Object
implements Serializable

Many class is a helper to define many-to-one or one-to-many or many-to-many relations.

This class provides two main static methods of and columns.

Mutation.builder("Mapping expression") .readable("string") .relation(Many.of("col1", "col2")).build(); ... Mutation.builder("Mapping expression") .readable("string") .relation("source", Many.columns("col3", "col4", "col5").build();

See Also:

Lineage, Mutation, Relation, Serialized Form

Method Summary

Modifier and Type	Method and Description
List<String>	columns()
static Many	columns(Collection<ColumnName> columns) List of ColumnName specified as source or target.
static Many	columns(ColumnName... columns) List of ColumnName specifying source or target.
static Many	columns(String... columns) List of columns of type String specifying either source or target.
static Many	of(Collection<String> columns) List of columns of type string as source or target.
static Many	of(String... columns) Method provides an easy way to translate ellipses parameters into a array of columns.

Methods inherited from class java.lang.Object

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

Method Detail

columns

public List<String> columns()

Returns:

a instance of

List

that returns columns associated with source or target.

of

public static Many of(String... columns)

Method provides an easy way to translate ellipses parameters into a array of columns.

Parameters:

columns - list source or target columns of type String.

Returns:

a instance of Many.

of

public static Many of(Collection<String> columns)

List of columns of type string as source or target.

Parameters:

columns - list source or target columns of type List of String.

Returns:

a instance of Many.

columns

public static Many columns(Collection<ColumnName> columns)

List of ColumnName specified as source or target. The method will convert the ColumnName to string.

Parameters:

columns - list source or target columns of type List of ColumnName.

Returns:

a instance of Many.

columns

public static Many columns(ColumnName... columns)

List of ColumnName specifying source or target.

Parameters:

columns - list source or target columns of type ColumnName.

Returns:

a instance of Many.

columns

public static Many columns(String... columns)

List of columns of type String specifying either source or target.

Parameters:

columns - list source or target columns of type String.

Returns:

a instance of Many.