UniquePredicate

java.lang.Object
- org.apache.commons.collections4.functors.UniquePredicate<T>

All Implemented Interfaces:

java.io.Serializable, Predicate<T>
```
public final class UniquePredicate<T>
extends java.lang.Object
implements Predicate<T>, java.io.Serializable
```
Predicate implementation that returns true the first time an object is passed into the predicate.

Since:

3.0

See Also:

Serialized Form

Field Summary

Fields
Modifier and Type Field Description

private java.util.Set<T> iSet
The set of previously seen objects

private static long serialVersionUID
Serial version UID

Constructor Summary

Constructors
Constructor Description

UniquePredicate()
Constructor that performs no validation.

Method Summary

All Methods Static Methods Instance Methods Concrete Methods
Modifier and Type	Method	Description
`boolean`	`evaluate(T object)`	Evaluates the predicate returning true if the input object hasn't been received yet.
`static <T> Predicate<T>`	`uniquePredicate()`	Factory to create the predicate.

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

- Field Detail
  - serialVersionUID
```
private static final long serialVersionUID
```
    Serial version UID
    
    See Also:
    
    Constant Field Values
  - iSet
```
private final java.util.Set<T> iSet
```
    The set of previously seen objects
- Constructor Detail
  - UniquePredicate
```
public UniquePredicate()
```
    Constructor that performs no validation. Use uniquePredicate if you want that.
- Method Detail
  - uniquePredicate
```
public static <T> Predicate<T> uniquePredicate()
```
    Factory to create the predicate.
    
    Type Parameters:
    
    T - the type that the predicate queries
    
    Returns:
    
    the predicate
    
    Throws:
    
    java.lang.IllegalArgumentException - if the predicate is null
  - evaluate
```
public boolean evaluate(T object)
```
    Evaluates the predicate returning true if the input object hasn't been received yet.
    
    Specified by:
    
    evaluate in interface Predicate<T>
    
    Parameters:
    
    object - the input object
    
    Returns:
    
    true if this is the first time the object is seen