content: /**
   * Licensed under the Apache License, Version 2.0 (the "License");
   * you may not use this file except in compliance with the License.
   * You may obtain a copy of the License at
   *
   *     http://www.apache.org/licenses/LICENSE-2.0
   *
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS,
   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   * See the License for the specific language governing permissions and
   * limitations under the License.
   */
  package org.apache.aurora.common.zookeeper;
  
  import com.google.common.base.Objects;
  import com.google.common.base.Preconditions;
  
  import org.apache.aurora.common.base.MorePreconditions;
  import org.apache.commons.lang.builder.EqualsBuilder;
  
  import static java.util.Objects.requireNonNull;
  
  /**
   * Encapsulates a user's ZooKeeper credentials.
   */
  public final class Credentials {
  
    /**
     * Creates a set of credentials for the ZooKeeper digest authentication mechanism.
     *
     * @param username the username to authenticate with
     * @param password the password to authenticate with
     * @return a set of credentials that can be used to authenticate the zoo keeper client
     */
    public static Credentials digestCredentials(String username, String password) {
      MorePreconditions.checkNotBlank(username);
      Preconditions.checkNotNull(password);
  
      // TODO(John Sirois): DigestAuthenticationProvider is broken - uses platform default charset
      // (on server) and so we just have to hope here that clients are deployed in compatible jvms.
      // Consider writing and installing a version of DigestAuthenticationProvider that controls its
      // Charset explicitly.
      return new Credentials("digest", (username + ":" + password).getBytes());
    }
  
    private final String scheme;
    private final byte[] authToken;
  
    public Credentials(String scheme, byte[] authToken) {
      this.scheme = MorePreconditions.checkNotBlank(scheme);
      this.authToken = requireNonNull(authToken);
    }
  
    /**
     * Returns the authentication scheme these credentials are for.
     *
     * @return the scheme these credentials are for.
     */
    public String scheme() {
      return scheme;
    }
  
    /**
     * Returns the authentication token.
     *
     * @return the authentication token.
     */
    public byte[] authToken() {
      return authToken;
    }
  
    @Override
    public boolean equals(Object o) {
      if (!(o instanceof Credentials)) {
        return false;
      }
  
      Credentials other = (Credentials) o;
      return new EqualsBuilder()
          .append(scheme, other.scheme())
          .append(authToken, other.authToken())
          .isEquals();
    }
  
    @Override
    public int hashCode() {
      return Objects.hashCode(scheme, authToken);
    }
  }
  