How to invoke a method in java using reflection

by

Here’s a simple example of invoking a method using reflection involving primitives.

import java.lang.reflect.*;

public class ReflectionExample {
    public int test(int i) {
        return i + 1;
    }
    public static void main(String args[]) throws Exception {
        Method testMethod = ReflectionExample.class.getMethod("test", int.class);
        int result = (Integer) testMethod.invoke(new ReflectionExample(), 100);
        System.out.println(result); // 101
    }
}

To be robust, you should catch and handle all checked reflection-related exceptions NoSuchMethodException, IllegalAccessException, InvocationTargetException.

More Related Contents:

  1. What is the difference between instanceof and Class.isAssignableFrom(…)?
  2. At runtime, find all classes in a Java application that extend a base class
  3. Determining if an Object is of primitive type
  4. Java – Get a list of all Classes loaded in the JVM
  5. Get variable by name from a String
  6. Is a Java string really immutable?
  7. Reflection generic get field value
  8. Access to private inherited fields via reflection in Java
  9. Faster alternatives to Java’s reflection [closed]
  10. Getting the name of a method parameter
  11. Creating classes dynamically with Java
  12. How do I intercept a method invocation with standard java features (no AspectJ etc)?
  13. Is it bad practice to use Reflection in Unit testing? [duplicate]
  14. System.out is declared as static final and initialized with null? [duplicate]
  15. Java Reflection: Create an implementing class
  16. How do I invoke a private static method using reflection (Java)?
  17. Java reflection: Is the order of class fields and methods standardized?
  18. Field.get(obj) returns all nulls on injected CDI managed beans, while manually invoking getters return correct values
  19. Java seek a method with specific annotation and its annotation element
  20. Instantiate private inner class with java reflection
  21. How to get string name of a method in java?
  22. Retrieve only static fields declared in Java class
  23. Java: NoSuchMethodException when method clearly exists
  24. How can I determine the type of a generic field in Java?
  25. How to call a private method from outside a java class
  26. Check type of primitive field
  27. Automatically delegating all methods of a java class
  28. Get value of a parameter of an annotation in Java
  29. Cast via reflection and use of Class.cast() [duplicate]
  30. Using jars that use java.beans classes (Introspector, BeanInfo or PropertyDescriptor)

Leave a Comment