Package org.apache.flink.types

Interface Key<T>

All Superinterfaces:

Comparable<T>, IOReadableWritable, Serializable, Value

@Deprecated
@PublicEvolving
public interface Key<T>
extends Value, Comparable<T>

Deprecated.

The Key type is a relict of a deprecated and removed API and will be removed in future (2.0) versions as well.

This interface has to be implemented by all data types that act as key. Keys are used to establish relationships between values. A key must always be Comparable to other keys of the same type. In addition, keys must implement a correct Object.hashCode() method and Object.equals(Object) method to ensure that grouping on keys works properly.

This interface extends Value and requires to implement the serialization of its value.

See Also:

Value, IOReadableWritable, Comparable

Method Summary

Modifier and Type	Method	Description
boolean	equals(Object other)	Deprecated. Compares the object on equality with another object.
int	hashCode()	Deprecated. All keys must override the hash-code function to generate proper deterministic hash codes, based on their contents.

Methods inherited from interface java.lang.Comparable

compareTo

Methods inherited from interface org.apache.flink.core.io.IOReadableWritable

read, write

Method Detail

hashCode

int hashCode()

Deprecated.

All keys must override the hash-code function to generate proper deterministic hash codes, based on their contents.

Overrides:

hashCode in class Object

Returns:

The hash code of the key

equals

boolean equals(Object other)

Deprecated.

Compares the object on equality with another object.

Overrides:

equals in class Object

Parameters:

other - The other object to compare against.

Returns:

True, iff this object is identical to the other object, false otherwise.