Security Java

/*
Ciphers:
            None available.
KeyAgreeents:
            None available.
Macs:
            None available.
MessageDigests:
            SHA-512
            SHA1
            MD2
            SHA
            SHA ImplementedIn
            SHA-256
            MD5 ImplementedIn
            SHA-1
            MD5
            SHA-384
Signatures:
            OID.1.2.840.10040.4.3
            OID.1.2.840.113549.1.1.4
            SHA384withRSA
            1.3.14.3.2.29
            SHA512withRSA SupportedKeyClasses
            SHA/DSA
            SHA1withDSA KeySize
            NONEwithDSA SupportedKeyClasses
            OID.1.2.840.113549.1.1.5
            SHA512withRSA
            MD5withRSA
            DSS
            OID.1.2.840.113549.1.1.11
            SHA384withRSA SupportedKeyClasses
            SHA1withRSA
            MD5withRSA SupportedKeyClasses
            NONEwithDSA
            1.2.840.113549.1.1.4
            MD5andSHA1withRSA
            1.2.840.113549.1.1.11
            OID.1.2.840.113549.1.1.13
            1.3.14.3.2.27
            1.2.840.10040.4.3
            SHA256withRSA
            MD2withRSA SupportedKeyClasses
            1.2.840.113549.1.1.2
            1.2.840.113549.1.1.12
            RawDSA
            SHA1withDSA
            SHA1/DSA
            MD2withRSA
            1.3.14.3.2.13
            SHAwithDSA
            DSAWithSHA1
            1.2.840.113549.1.1.13
            OID.1.3.14.3.2.29
            SHA1withDSA ImplementedIn
            SHA256withRSA SupportedKeyClasses
            SHA1withDSA SupportedKeyClasses
            DSA
            1.2.840.113549.1.1.5
            SHA-1/DSA
            SHA1withRSA SupportedKeyClasses
            OID.1.2.840.113549.1.1.12
            OID.1.2.840.113549.1.1.2
 */
import java.security.Provider;
import java.security.Security;
import java.util.HashSet;
import java.util.Iterator;
import java.util.Set;
public class ListAlgorithms {
  public static void printSet(String setName, Set algorithms) {
    System.out.println(setName + ":");
    if (algorithms.isEmpty()) {
      System.out.println("            None available.");
    } else {
      Iterator it = algorithms.iterator();
      while (it.hasNext()) {
        String name = (String) it.next();
        System.out.println("            " + name);
      }
    }
  }
  public static void main(String[] args) {
    Provider[] providers = Security.getProviders();
    Set ciphers = new HashSet();
    Set keyAgreements = new HashSet();
    Set macs = new HashSet();
    Set messageDigests = new HashSet();
    Set signatures = new HashSet();
    for (int i = 0; i != providers.length; i++) {
      Iterator it = providers[i].keySet().iterator();
      while (it.hasNext()) {
        String entry = (String) it.next();
        if (entry.startsWith("Alg.Alias.")) {
          entry = entry.substring("Alg.Alias.".length());
        }
        if (entry.startsWith("Cipher.")) {
          ciphers.add(entry.substring("Cipher.".length()));
        } else if (entry.startsWith("KeyAgreement.")) {
          keyAgreements.add(entry.substring("KeyAgreement.".length()));
        } else if (entry.startsWith("Mac.")) {
          macs.add(entry.substring("Mac.".length()));
        } else if (entry.startsWith("MessageDigest.")) {
          messageDigests.add(entry.substring("MessageDigest.".length()));
        } else if (entry.startsWith("Signature.")) {
          signatures.add(entry.substring("Signature.".length()));
        }
      }
    }
    printSet("Ciphers", ciphers);
    printSet("KeyAgreeents", keyAgreements);
    printSet("Macs", macs);
    printSet("MessageDigests", messageDigests);
    printSet("Signatures", signatures);
  }
}