Difference between NoSuchMethodException and NoSuchMethodError in Java

Question

I can\'t find exact difference between NoSuchMethodException and NoSuchMethodError in Java. Could someone give explanation and example of these two th

Answer 1

NoSuchMethodException occurs when you try to invoke a method using reflection. NoSuchMethodError occurs when you had that method while compiling but dont have it during the runtime.

Consider the following example for NoSuchMethodError

Class : Person.java

public class Person{
      public String getName(){
         return "MyName";
     }
}

Compile it using javac Person.java And now try to run this using java Person

It ll give you

java.lang.NoSuchMethodError: main
Exception in thread "main"

Because it tries to find the public static void main(String [] args) which is not there

For NoSuchMethodException

c = Class.forName("java.lang.String");
  try
  {
    Class[] paramTypes = new Class[2];
    Method m = c.getDeclaredMethod("myMethod", paramTypes);
  }

this is ll throw an exception saying

java.lang.NoSuchMethodException: java.lang.String.myMethod(null, null)

Consider this link which has a better explaination