Tag (Hazelcast Root 5.4.0-SNAPSHOT API)

java.lang.Object
- com.hazelcast.jet.datamodel.Tag<T>

Type Parameters:

T - the type of the data associated with the tag

All Implemented Interfaces:

java.io.Serializable, java.lang.Comparable<Tag<?>>
```
public final class Tag<T>
extends java.lang.Object
implements java.lang.Comparable<Tag<?>>, java.io.Serializable
```
A tag object useful as a key in heterogeneous maps. Carries static type information in its type parameter, which is expected to correspond to the type of the item retrieved from the map.
Tags are also used by hash-join and co-group builder objects. The same tag supplied to the builder is used to retrieve the data from the heterogeneous maps (ItemsByTag) that appear in the output.

Since:

Jet 3.0

See Also:

Serialized Form

Method Summary

All Methods Static Methods Instance Methods Concrete Methods
Modifier and Type	Method	Description
`int`	`compareTo(Tag<?> that)`
`boolean`	`equals(java.lang.Object obj)`
`int`	`hashCode()`
`int`	`index()`	Returns the index associated with this tag.
`static <T> Tag<T>`	`tag(int index)`	Returns a tag object associated with the specified index.
`static <T> Tag<T>`	`tag0()`	Returns the tag constant `TAG_0`.
`static <T> Tag<T>`	`tag1()`	Returns the tag constant `TAG_1`.
`static <T> Tag<T>`	`tag2()`	Returns the tag constant `TAG_2`.
`java.lang.String`	`toString()`

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

- Method Detail
  - tag
```
public static <T> Tag<T> tag(int index)
```
    Returns a tag object associated with the specified index. The tag's type parameter is inferred from the call site. The method will not necessarily create a new tag object.
  - index
```
public int index()
```
    Returns the index associated with this tag. It can refer to the index of a contributing stream in a hash-join or co-group operation, or to the index used internally to store the data associated with the tag.
  - tag0
```
public static <T> Tag<T> tag0()
```
    Returns the tag constant TAG_0.
  - tag1
```
public static <T> Tag<T> tag1()
```
    Returns the tag constant TAG_1.
  - tag2
```
public static <T> Tag<T> tag2()
```
    Returns the tag constant TAG_2.
  - equals
```
public boolean equals(java.lang.Object obj)
```
    Overrides:
    
    equals in class java.lang.Object
  - hashCode
```
public int hashCode()
```
    Overrides:
    
    hashCode in class java.lang.Object
  - compareTo
```
public int compareTo(Tag<?> that)
```
    Specified by:
    
    compareTo in interface java.lang.Comparable<T>
  - toString
```
public java.lang.String toString()
```
    Overrides:
    
    toString in class java.lang.Object