code: public void set(String name, Object obj) throws IOException {
          if (!(obj instanceof Boolean)) {
              throw new IOException("Attribute must be of type Boolean.");
          }
          boolean val = ((Boolean)obj).booleanValue();
          if (name.equalsIgnoreCase(DIGITAL_SIGNATURE)) {
              set(0,val);
          } else if (name.equalsIgnoreCase(NON_REPUDIATION)) {
              set(1,val);
          } else if (name.equalsIgnoreCase(KEY_ENCIPHERMENT)) {
              set(2,val);
          } else if (name.equalsIgnoreCase(DATA_ENCIPHERMENT)) {
              set(3,val);
          } else if (name.equalsIgnoreCase(KEY_AGREEMENT)) {
              set(4,val);
          } else if (name.equalsIgnoreCase(KEY_CERTSIGN)) {
              set(5,val);
          } else if (name.equalsIgnoreCase(CRL_SIGN)) {
              set(6,val);
          } else if (name.equalsIgnoreCase(ENCIPHER_ONLY)) {
              set(7,val);
          } else if (name.equalsIgnoreCase(DECIPHER_ONLY)) {
              set(8,val);
          } else {
            throw new IOException("Attribute name not recognized by"
                                  + " CertAttrSet:KeyUsage.");
          }
          encodeThis();
      }
docs: Set the attribute value.