Java/Security/Keytool

Creating a New Key Pair and Self-Signed Certificate Using keytool

   
keytool -genkey -alias alias -keystore .keystore

Export certificate in binary using keytool, if the certificate is in the key store

   
keytool -storepass my-keystore-password -alias myalias -export -file outfilename.cer

Export certificate in text format using keytool, if the certificate is in the key store

   

keytool -storepass my-keystore-password -alias myalias -export -rfc -file outfilename.cer

generates a 1024-bit Digital Signature Algorithm (DSA) key pair.

   
keytool -genkey -alias alias -keystore .keystore

Java Key Tools

  
import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.ObjectOutputStream;
import java.security.Key;
import java.security.KeyPair;
import java.security.KeyPairGenerator;
import java.security.SecureRandom;
public class KeyTools {
  public static void writeToFile(Key key, File file) throws IOException {
    FileOutputStream fileoutputstream = new FileOutputStream(file);
    ObjectOutputStream objectoutputstream = new ObjectOutputStream(fileoutputstream);
    objectoutputstream.writeObject(key);
    objectoutputstream.close();
  }
  public static void main(String[] rgstring) {
    try {
      File filePublic = new File(rgstring[0]);
      File filePrivate = new File(rgstring[1]);
      KeyPairGenerator keypairgenerator = KeyPairGenerator.getInstance("DSA");
      keypairgenerator.initialize(1024, new SecureRandom());
      KeyPair keypair = keypairgenerator.generateKeyPair();
      
      writeToFile(keypair.getPublic(), filePublic);
      writeToFile(keypair.getPrivate(), filePrivate);
    } catch (Exception ex) {
      ex.printStackTrace();
    }
  }
}

To create a 1024-bit RSA key:

   
keytool -genkey -keyalg RSA -keysize 1024 -alias alias -keystore .keystore

using keytool to import a certificate into a keystore

   
keytool -storepass my-keystore-password -alias myalias -import -file infilename.cer