com.abubusoft.kripton.common.Function Maven / Gradle / Ivy
Show all versions of kripton-core Show documentation
package com.abubusoft.kripton.common;
/**
* Determines an output value based on an input value.
*
* The {@link Functions} class provides common functions and related utilites.
*
*
See the Guava User Guide article on the use of {@code
* Function}.
*
* @author Kevin Bourrillion
* @since 2.0 (imported from Google Collections Library)
*/
public interface Function {
/**
* Returns the result of applying this function to {@code input}. This method is generally
* expected, but not absolutely required, to have the following properties:
*
*
* - Its execution does not cause any observable side effects.
*
- The computation is consistent with equals; that is, {@link Objects#equal
* Objects.equal}{@code (a, b)} implies that {@code Objects.equal(function.apply(a),
* function.apply(b))}.
*
*
* @throws NullPointerException if {@code input} is null and this function does not accept null
* arguments
*/
T apply(F input);
/**
* Indicates whether another object is equal to this function.
*
* Most implementations will have no reason to override the behavior of {@link Object#equals}.
* However, an implementation may also choose to return {@code true} whenever {@code object} is a
* {@link Function} that it considers interchangeable with this one. "Interchangeable"
* typically means that {@code Objects.equal(this.apply(f), that.apply(f))} is true for all
* {@code f} of type {@code F}. Note that a {@code false} result from this method does not imply
* that the functions are known not to be interchangeable.
*/
@Override
boolean equals(Object object);
}