Along with lambdas, Java SE 8 brought method references to the Java language. This tutorial offers a brief overview of method references in Java, then gets you started using them with Java code ...

Method and variable handles vs. Java reflection To truly understand MethodHandles and VarHandles —what they do and why they are useful—it’s helpful to know a few things about reflection in Java.

There is a reason why Java method modifiers exist. If you call public methods internally and don't understand why, your developers could face major class issues.