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Java

secp256k1 Key Generation and Keccak-256

See more ECC Examples

Starting in v11.0.0, Chilkat supports both secp256k1 key generation and Keccak-256 directly. These algorithms are typically used for Bitcoin and Ethereum.

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Java
import com.chilkatsoft.*;

public class ChilkatExample {

  static {
    try {
        System.loadLibrary("chilkat");
    } catch (UnsatisfiedLinkError e) {
      System.err.println("Native code library failed to load.\n" + e);
      System.exit(1);
    }
  }

  public static void main(String argv[])
  {
    boolean success = false;

    // This example requires the Chilkat API to have been previously unlocked.
    // See Global Unlock Sample for sample code.

    // Create a Fortuna PRNG and seed it with system entropy.
    // This will be our source of random data for generating the ECDSA private key.
    CkPrng fortuna = new CkPrng();
    String entropy = fortuna.getEntropy(32,"base64");
    success = fortuna.AddEntropy(entropy,"base64");

    CkEcc ecc = new CkEcc();

    // Generate a random ECDSA private key on the secp256k1 curve.
    CkPrivateKey privKey = new CkPrivateKey();
    success = ecc.GenKey("secp256k1",fortuna,privKey);
    if (success == false) {
        System.out.println(ecc.lastErrorText());
        return;
        }

    System.out.println("Successfully generated a sec256k1 key.");

    // Show how to compute the Keccak-256 hash in a few ways.
    CkStringBuilder sb = new CkStringBuilder();
    sb.Append("hello");

    System.out.println("keccak-256: " + sb.getHash("keccak-256","hex_lower","utf-8"));

    // Output:
    // keccak-256: 1c8aff950685c2ed4bc3174f3472287b56d9517b9c948127319a09a7a36deac8

    // To keccak-256 hash binary data
    CkBinData bd = new CkBinData();
    bd.AppendEncoded("00010203040506","hex");

    System.out.println("keccak-256: " + bd.getHash("keccak-256","hex_lower"));

    // Output:
    // keccak-256: 801560412425120fa609be232d6fa71c7f64f42aee7977267687dcc0a2f5aa63
  }
}