What is Reflection in Java

Reflection is a mechanism for obtaining data about a program during its execution (runtime). In Java, Reflection is implemented using the Java Reflection API, which consists of the package classes java.lang and java.lang.reflect.

Java Reflection API features:

  • Object class definition;
  • Getting information about class modifiers, fields, methods, constructors and superclasses;
  • Defining the interfaces implemented by the class;
  • Creating an instance of the class;
  • Getting and setting values of object fields;
  • Calling object methods;
  • Creation of a new array.

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