Check out example codes for "what is getService() in java". It will help you in understanding the concepts better.

Code Example 1

import java.security.*;
import java.util.*;
public class Demo {
   public static void main(String[] argv) throws Exception {
      try {
         Signature sign = Signature.getInstance("SHA256withDSA");
         Provider p = sign.getProvider();
      
      }
   }
}

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