ChunkedFile.java

/**
 * Licensed to The Apereo Foundation under one or more contributor license
 * agreements. See the NOTICE file distributed with this work for additional
 * information regarding copyright ownership.
 *
 *
 * The Apereo Foundation licenses this file to you under the Educational
 * Community 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://opensource.org/licenses/ecl2.txt
 *
 * 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.opencastproject.util;

import java.io.File;
import java.io.IOException;

public class ChunkedFile {

  private File file;
  private long contentLength;
  private long offset;

  /**
   *
   * @param file the file containing the data
   * @throws IOException if an error occured
   */
  public ChunkedFile(File file) throws IOException {
    this(file, 0, file.length());
  }

  /**
   * Creates a new instance that fetches data from the specified file.
   *
   * @param offset the offset of the file where the transfer begins
   * @param contentLength the number of bytes to transfer
   */
  public ChunkedFile(File file, long offset, long contentLength)
      throws IOException {
    if (file == null) {
      throw new NullPointerException("file");
    }
    if (offset < 0) {
      throw new IllegalArgumentException("offset: " + offset + " (expected: 0 or greater)");
    }
    if (contentLength < 0) {
      throw new IllegalArgumentException("length: " + contentLength + " (expected: 0 or greater)");
    }

    this.file = file;
    this.offset = offset;
    this.contentLength = contentLength;

  }

  /**
   * @return the offset in the file where the transfer began.
   */
  public long getOffset() {
    return offset;
  }

  /**
   * @return the file
   */
  public File getFile() {
    return file;
  }

  /**
   * @return the size of the content
   */
  public long getContentLength() {
    return contentLength;
  }
}