http://www.bouncycastle.org/java.html: The Bouncy Castle Crypto package is a Java implementation of cryptographic algorithms. This jar contains JCE provider and lightweight API for the Bouncy Castle Cryptography APIs for JDK 1.5. 
public class org.bouncycastle.jce.provider.JCESecretKeyFactory$DES extends org.bouncycastle.jce.provider.JCESecretKeyFactory
  minor version: 0
  major version: 59
  flags: flags: (0x0021) ACC_PUBLIC, ACC_SUPER
  this_class: org.bouncycastle.jce.provider.JCESecretKeyFactory$DES
  super_class: org.bouncycastle.jce.provider.JCESecretKeyFactory
{
  public void <init>();
    descriptor: ()V
    flags: (0x0001) ACC_PUBLIC
    Code:
      stack=3, locals=1, args_size=1
        start local 0 // org.bouncycastle.jce.provider.JCESecretKeyFactory$DES this
         0: .line 236
            aload 0 /* this */
            ldc "DES"
            aconst_null
            invokespecial org.bouncycastle.jce.provider.JCESecretKeyFactory.<init>:(Ljava/lang/String;Lorg/bouncycastle/asn1/DERObjectIdentifier;)V
         1: .line 237
            return
        end local 0 // org.bouncycastle.jce.provider.JCESecretKeyFactory$DES this
      LocalVariableTable:
        Start  End  Slot  Name  Signature
            0    2     0  this  Lorg/bouncycastle/jce/provider/JCESecretKeyFactory$DES;

  protected javax.crypto.SecretKey engineGenerateSecret(java.security.spec.KeySpec);
    descriptor: (Ljava/security/spec/KeySpec;)Ljavax/crypto/SecretKey;
    flags: (0x0004) ACC_PROTECTED
    Code:
      stack=4, locals=3, args_size=2
        start local 0 // org.bouncycastle.jce.provider.JCESecretKeyFactory$DES this
        start local 1 // java.security.spec.KeySpec keySpec
         0: .line 243
            aload 1 /* keySpec */
            instanceof javax.crypto.spec.DESKeySpec
            ifeq 3
         1: .line 245
            aload 1 /* keySpec */
            checkcast javax.crypto.spec.DESKeySpec
            astore 2 /* desKeySpec */
        start local 2 // javax.crypto.spec.DESKeySpec desKeySpec
         2: .line 246
            new javax.crypto.spec.SecretKeySpec
            dup
            aload 2 /* desKeySpec */
            invokevirtual javax.crypto.spec.DESKeySpec.getKey:()[B
            ldc "DES"
            invokespecial javax.crypto.spec.SecretKeySpec.<init>:([BLjava/lang/String;)V
            areturn
        end local 2 // javax.crypto.spec.DESKeySpec desKeySpec
         3: .line 249
      StackMap locals:
      StackMap stack:
            aload 0 /* this */
            aload 1 /* keySpec */
            invokespecial org.bouncycastle.jce.provider.JCESecretKeyFactory.engineGenerateSecret:(Ljava/security/spec/KeySpec;)Ljavax/crypto/SecretKey;
            areturn
        end local 1 // java.security.spec.KeySpec keySpec
        end local 0 // org.bouncycastle.jce.provider.JCESecretKeyFactory$DES this
      LocalVariableTable:
        Start  End  Slot        Name  Signature
            0    4     0        this  Lorg/bouncycastle/jce/provider/JCESecretKeyFactory$DES;
            0    4     1     keySpec  Ljava/security/spec/KeySpec;
            2    3     2  desKeySpec  Ljavax/crypto/spec/DESKeySpec;
    Exceptions:
      throws java.security.spec.InvalidKeySpecException
    MethodParameters:
         Name  Flags
      keySpec  
}
SourceFile: "JCESecretKeyFactory.java"
NestHost: org.bouncycastle.jce.provider.JCESecretKeyFactory
InnerClasses:
  public DES = org.bouncycastle.jce.provider.JCESecretKeyFactory$DES of org.bouncycastle.jce.provider.JCESecretKeyFactory