content: /**
   * Licensed to the Apache Software Foundation (ASF) under one
   * or more contributor license agreements.  See the NOTICE file
   * distributed with this work for additional information
   * regarding copyright ownership.  The ASF licenses this file
   * to you 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.hive.service.auth;
  
  import javax.security.sasl.AuthenticationException;
  
  /**
   * This class helps select a {@link PasswdAuthenticationProvider} for a given {@code AuthMethod}.
   */
  public final class AuthenticationProviderFactory {
  
    public enum AuthMethods {
      LDAP("LDAP"),
      PAM("PAM"),
      CUSTOM("CUSTOM"),
      NONE("NONE");
  
      private final String authMethod;
  
      AuthMethods(String authMethod) {
        this.authMethod = authMethod;
      }
  
      public String getAuthMethod() {
        return authMethod;
      }
  
      public static AuthMethods getValidAuthMethod(String authMethodStr)
        throws AuthenticationException {
        for (AuthMethods auth : AuthMethods.values()) {
          if (authMethodStr.equals(auth.getAuthMethod())) {
            return auth;
          }
        }
        throw new AuthenticationException("Not a valid authentication method");
      }
    }
  
    private AuthenticationProviderFactory() {
    }
  
    public static PasswdAuthenticationProvider getAuthenticationProvider(AuthMethods authMethod)
      throws AuthenticationException {
      if (authMethod == AuthMethods.LDAP) {
        return new LdapAuthenticationProviderImpl();
      } else if (authMethod == AuthMethods.PAM) {
        return new PamAuthenticationProviderImpl();
      } else if (authMethod == AuthMethods.CUSTOM) {
        return new CustomAuthenticationProviderImpl();
      } else if (authMethod == AuthMethods.NONE) {
        return new AnonymousAuthenticationProviderImpl();
      } else {
        throw new AuthenticationException("Unsupported authentication method");
      }
    }
  }
  