001/*
002 * Copyright (c) 2016-2018 Chris K Wensel <chris@wensel.net>. All Rights Reserved.
003 * Copyright (c) 2007-2017 Xplenty, Inc. All Rights Reserved.
004 *
005 * Project and contact information: http://www.cascading.org/
006 *
007 * This file is part of the Cascading project.
008 *
009 * Licensed under the Apache License, Version 2.0 (the "License");
010 * you may not use this file except in compliance with the License.
011 * You may obtain a copy of the License at
012 *
013 *     http://www.apache.org/licenses/LICENSE-2.0
014 *
015 * Unless required by applicable law or agreed to in writing, software
016 * distributed under the License is distributed on an "AS IS" BASIS,
017 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
018 * See the License for the specific language governing permissions and
019 * limitations under the License.
020 */
021
022package cascading.tap.type;
023
024import java.io.IOException;
025
026import cascading.flow.FlowProcess;
027
028/** Interface FileType marks specific platform {@link cascading.tap.Tap} classes as representing a file like interface. */
029public interface FileType<Config>
030  {
031  String CASCADING_SOURCE_PATH = "cascading.source.path";
032
033  /**
034   * Method isDirectory returns true if the underlying resource represents a directory or folder instead
035   * of an individual file.
036   *
037   * @param flowProcess
038   * @return boolean
039   * @throws java.io.IOException
040   */
041  boolean isDirectory( FlowProcess<? extends Config> flowProcess ) throws IOException;
042
043  /**
044   * Method isDirectory returns true if the underlying resource represents a directory or folder instead
045   * of an individual file.
046   *
047   * @param conf of Conf
048   * @return boolean
049   * @throws java.io.IOException
050   */
051  boolean isDirectory( Config conf ) throws IOException;
052
053  /**
054   * Method getChildIdentifiers returns an array of child identifiers if this resource is a directory.
055   * <p>
056   * This method will skip Hadoop log directories ({@code _log}).
057   *
058   * @param flowProcess of type FlowProcess
059   * @return String[]
060   * @throws java.io.IOException
061   */
062  String[] getChildIdentifiers( FlowProcess<? extends Config> flowProcess ) throws IOException;
063
064  /**
065   * Method getChildIdentifiers returns an array of child identifiers if this resource is a directory.
066   * <p>
067   * This method will skip Hadoop log directories ({@code _log}).
068   *
069   * @param conf of type Conf
070   * @return String[]
071   * @throws IOException
072   */
073  String[] getChildIdentifiers( Config conf ) throws IOException;
074
075  /**
076   * Method getChildIdentifiers returns an array of child identifiers if this resource is a directory.
077   * <p>
078   * This method will skip Hadoop log directories ({@code _log}).
079   * <p>
080   * Note that all files encountered up to depth will be returned, and no directories unless
081   * the directory is the final path at max depth.
082   *
083   * @param flowProcess
084   * @param depth
085   * @param fullyQualified
086   * @return String{}
087   * @throws IOException
088   */
089  String[] getChildIdentifiers( FlowProcess<? extends Config> flowProcess, int depth, boolean fullyQualified ) throws IOException;
090
091  /**
092   * Method getChildIdentifiers returns an array of child identifiers if this resource is a directory.
093   * <p>
094   * This method will skip Hadoop log directories ({@code _log}).
095   * <p>
096   * Note that all files encountered up to depth will be returned, and no directories unless
097   * the directory is the final path at max depth.
098   *
099   * @param conf           of type Conf
100   * @param depth          the max depth to return.
101   * @param fullyQualified true if the returned paths should be fully qualified
102   * @return String[]
103   * @throws IOException
104   */
105  String[] getChildIdentifiers( Config conf, int depth, boolean fullyQualified ) throws IOException;
106
107  /**
108   * Method getSize returns the size of the file referenced by this tap.
109   *
110   * @param flowProcess
111   * @return The size of the file reference by this tap.
112   * @throws java.io.IOException
113   */
114  long getSize( FlowProcess<? extends Config> flowProcess ) throws IOException;
115
116  /**
117   * Method getSize returns the size of the file referenced by this tap.
118   *
119   * @param conf of type Config
120   * @return The size of the file reference by this tap.
121   * @throws java.io.IOException
122   */
123  long getSize( Config conf ) throws IOException;
124  }