title: What are practical uses of the java.util.function.Function.identity method?
body: <p>Why should I use Function.identity() when it returns the same thing which it receives without doing anything using the input or modifying the input in some way?</p>
  
  <pre><code>Apple apple = new Apple(10, "green");
  Function&lt;Apple, Apple&gt; identity = Function.identity();
  identity.apply(apple);
  </code></pre>
  
  <p>There must be some practical usage of this which I am not able to figure out.</p>