Note that the forEach method in Java’s Iterable interface (which List extends) expects a single argument that matches the Consumer functional interface you saw in a previous example.

See the Java 101 Java interfaces tutorial for a more in-depth introduction to using interfaces in your Java programs, including where and where not to use default, static, and private methods.

There is a reason why Java method modifiers exist. ... You will notice that we have updateCustomerOrderAsShipped-- a public method in the interface or class -- making a call to another public method ...

Lambda and Consumer interface example. As you can see, there is nothing special about the interfaces defined in the java.util.function package. They are regular Java interfaces that comply with all of ...