/*
    * 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.commons.vfs2.provider.hdfs;
  
  import java.io.IOException;
  import java.io.InputStream;
  
  import org.apache.commons.vfs2.provider.AbstractRandomAccessContent;
  import org.apache.commons.vfs2.util.RandomAccessMode;
  import org.apache.hadoop.fs.FSDataInputStream;
  import org.apache.hadoop.fs.FileSystem;
  import org.apache.hadoop.fs.Path;
  
  /**
   * Provides random access to content in an HdfsFileObject. Currently this only supports read operations. All write
   * operations throw an {@link UnsupportedOperationException}.
   *
   * @since 2.1
   */
  public class HdfsRandomAccessContent extends AbstractRandomAccessContent {
  
      private final FSDataInputStream fis;
      private final FileSystem fs;
      private final Path path;
  
      /**
       * Create random access content.
       *
       * @param path A Hadoop Path
       * @param fs A Hadoop FileSystem
       * @throws IOException when the path cannot be processed.
       */
      public HdfsRandomAccessContent(final Path path, final FileSystem fs) throws IOException {
          super(RandomAccessMode.READ);
          this.fs = fs;
          this.path = path;
          this.fis = this.fs.open(this.path);
      }
  
      /**
       * @see org.apache.commons.vfs2.RandomAccessContent#close()
       */
      @Override
      public void close() throws IOException {
          this.fis.close();
      }
  
      /**
       * @see org.apache.commons.vfs2.RandomAccessContent#getFilePointer()
       */
      @Override
      public long getFilePointer() throws IOException {
          return this.fis.getPos();
      }
  
      /**
       * @see org.apache.commons.vfs2.RandomAccessContent#getInputStream()
       */
      @Override
      public InputStream getInputStream() throws IOException {
          return this.fis;
      }
  
      /**
       * @see org.apache.commons.vfs2.RandomAccessContent#length()
       */
      @Override
      public long length() throws IOException {
          return this.fs.getFileStatus(this.path).getLen();
      }
  
      /**
       * @see java.io.DataInput#readBoolean()
       */
      @Override
      public boolean readBoolean() throws IOException {
          return this.fis.readBoolean();
      }
  
      /**
       * @see java.io.DataInput#readByte()
       */
      @Override
      public byte readByte() throws IOException {
          return this.fis.readByte();
     }
 
     /**
      * @see java.io.DataInput#readChar()
      */
     @Override
     public char readChar() throws IOException {
         return this.fis.readChar();
     }
 
     /**
      * @see java.io.DataInput#readDouble()
      */
     @Override
     public double readDouble() throws IOException {
         return this.fis.readDouble();
     }
 
     /**
      * @see java.io.DataInput#readFloat()
      */
     @Override
     public float readFloat() throws IOException {
         return this.fis.readFloat();
     }
 
     /**
      * @see java.io.DataInput#readFully(byte[])
      */
     @Override
     public void readFully(final byte[] b) throws IOException {
         throw new UnsupportedOperationException();
     }
 
     /**
      * @see java.io.DataInput#readFully(byte[], int, int)
      */
     @Override
     public void readFully(final byte[] b, final int off, final int len) throws IOException {
         throw new UnsupportedOperationException();
     }
 
     /**
      * @see java.io.DataInput#readInt()
      */
     @Override
     public int readInt() throws IOException {
         return this.fis.readInt();
     }
 
     /**
      * @see java.io.DataInput#readLine()
      */
     @Override
     @SuppressWarnings("deprecation")
     public String readLine() throws IOException {
         return this.fis.readLine();
     }
 
     /**
      * @see java.io.DataInput#readLong()
      */
     @Override
     public long readLong() throws IOException {
         return this.fis.readLong();
     }
 
     /**
      * @see java.io.DataInput#readShort()
      */
     @Override
     public short readShort() throws IOException {
         return this.fis.readShort();
     }
 
     /**
      * @see java.io.DataInput#readUnsignedByte()
      */
     @Override
     public int readUnsignedByte() throws IOException {
         return this.fis.readUnsignedByte();
     }
 
     /**
      * @see java.io.DataInput#readUnsignedShort()
      */
     @Override
     public int readUnsignedShort() throws IOException {
         return this.fis.readUnsignedShort();
     }
 
     /**
      * @see java.io.DataInput#readUTF()
      */
     @Override
     public String readUTF() throws IOException {
         return this.fis.readUTF();
     }
 
     /**
      * @see org.apache.commons.vfs2.RandomAccessContent#seek(long)
      */
     @Override
     public void seek(final long pos) throws IOException {
         this.fis.seek(pos);
     }
 
     /**
      * @see org.apache.commons.vfs2.RandomAccessContent#setLength(long)
      */
     @Override
     public void setLength(final long newLength) throws IOException {
         throw new UnsupportedOperationException();
     }
 
     /**
      * @see java.io.DataInput#skipBytes(int)
      */
     @Override
     public int skipBytes(final int n) throws IOException {
         throw new UnsupportedOperationException();
     }
 
 }