import java.security.InvalidKeyException;
import java.security.KeyPair;
import java.security.KeyPairGenerator;
import java.security.NoSuchAlgorithmException;
import java.security.PrivateKey;
import java.security.PublicKey;
import java.security.SecureRandom;
import java.security.Signature;
import java.security.SignatureException;

public class EC {
	public static void main(String[] args) {
		byte[] message = "The quick brown fox jumps over the lazy dog"
				.getBytes();
		byte[] sign = null;

		KeyPairGenerator keyPairGenerator = null;
		long generateKeyPairStart;
		long generateKeyPairEnd;
		try {
			keyPairGenerator = KeyPairGenerator.getInstance("EC");
		} catch (NoSuchAlgorithmException e) {
			e.printStackTrace();
			return;
		}
		SecureRandom secureRandom = new SecureRandom();

		keyPairGenerator.initialize(256, secureRandom);

		generateKeyPairStart = System.nanoTime();
		KeyPair keyPair = keyPairGenerator.generateKeyPair();
		generateKeyPairEnd = System.nanoTime();
		
		PrivateKey privateKey = keyPair.getPrivate();
		PublicKey publicKey = keyPair.getPublic();

		Signature signatureSign = null;
		long signStart = 0;
		long signEnd = 0;
		try {
			signatureSign = Signature.getInstance("NONEwithECDSA");
			signatureSign.initSign(privateKey, secureRandom);
			signatureSign.update(message);
			
			signStart = System.nanoTime();
			sign = signatureSign.sign();
			signEnd = System.nanoTime();
		} catch (NoSuchAlgorithmException e) {
			e.printStackTrace();
			return;
		} catch (InvalidKeyException e) {
			e.printStackTrace();
			return;
		} catch (SignatureException e) {
			e.printStackTrace();
			return;
		}

		Signature signatureVerify = null;
		boolean verifyResult;
		long verifyStart;
		long verifyEnd;
		try {
			signatureVerify = Signature.getInstance("NONEwithECDSA");
			signatureVerify.initVerify(publicKey);
			signatureVerify.update(message);
			
			verifyStart = System.nanoTime();
			verifyResult = signatureVerify.verify(sign);
			verifyEnd = System.nanoTime();
			
			if (verifyResult) {
				System.out.print("OK");
				System.out.print("\t");
			} else {
				System.out.print("NG");
				System.out.print("\t");
			}
		} catch (NoSuchAlgorithmException e) {
			e.printStackTrace();
			return;
		} catch (InvalidKeyException e) {
			e.printStackTrace();
			return;
		} catch (SignatureException e) {
			e.printStackTrace();
			return;
		}

		System.out.print(generateKeyPairEnd - generateKeyPairStart);
		System.out.print("\t");
		System.out.print(signEnd - signStart);
		System.out.print("\t");
		System.out.print(verifyEnd - verifyStart);
		System.out.println();
	}
}