content: /*
   * The Alluxio Open Foundation licenses this work under the Apache License, version 2.0
   * (the "License"). You may not use this work except in compliance with the License, which is
   * available at www.apache.org/licenses/LICENSE-2.0
   *
   * This software is distributed on an "AS IS" basis, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND,
   * either express or implied, as more fully set forth in the License.
   *
   * See the NOTICE file distributed with this work for information regarding copyright ownership.
   */
  
  package alluxio.fuse.auth;
  
  import alluxio.client.file.FileSystem;
  import alluxio.conf.AlluxioConfiguration;
  import alluxio.conf.PropertyKey;
  import alluxio.exception.runtime.InvalidArgumentRuntimeException;
  import alluxio.jnifuse.FuseFileSystem;
  
  import java.lang.reflect.InvocationTargetException;
  import java.lang.reflect.Method;
  import java.util.Optional;
  
  /**
   * Fuse Auth Policy Factory.
   */
  public class AuthPolicyFactory {
  
    /**
     * Creates a new instance of {@link AuthPolicy}.
     *
     * @param fileSystem the Alluxio file system
     * @param conf the Alluxio configuration containing Fuse options
     * @param fuseFileSystem the FuseFileSystem
     * @return AuthPolicy
     */
    public static AuthPolicy create(FileSystem fileSystem,
        AlluxioConfiguration conf, FuseFileSystem fuseFileSystem) {
      Class<?> authPolicyClazz = conf.getClass(PropertyKey.FUSE_AUTH_POLICY_CLASS);
      if (!AuthPolicy.class.isAssignableFrom(authPolicyClazz)) {
        throw new InvalidArgumentRuntimeException(String.format(
            "Cannot configure %s to %s, policy description: %s",
            PropertyKey.FUSE_AUTH_POLICY_CLASS.getName(), authPolicyClazz,
            PropertyKey.FUSE_AUTH_POLICY_CLASS.getDescription()));
      }
      try {
        Class<? extends AuthPolicy> subAuthPolicyClazz = authPolicyClazz
            .asSubclass(AuthPolicy.class);
        Method createMethod = subAuthPolicyClazz.getMethod("create",
            FileSystem.class, AlluxioConfiguration.class, Optional.class);
        AuthPolicy authPolicy = (AuthPolicy) createMethod
            .invoke(null, fileSystem, conf, Optional.of(fuseFileSystem));
        authPolicy.init();
        return authPolicy;
      } catch (ClassCastException e) {
        throw new InvalidArgumentRuntimeException(String.format(
            "Cannot configure %s to %s, policy description: %s",
            PropertyKey.FUSE_AUTH_POLICY_CLASS.getName(), authPolicyClazz,
            PropertyKey.FUSE_AUTH_POLICY_CLASS.getDescription()), e);
      } catch (NoSuchMethodException | IllegalArgumentException
          | IllegalAccessException | InvocationTargetException ne) {
        throw new InvalidArgumentRuntimeException(
            String.format("Failed to create %s: should not be reached here",
                authPolicyClazz.getName()), ne);
      }
    }
  }
  