Memory issues with InputStream in Java

Question

I need to read a file into an array of Bytes.The entire file needs to be read into the array. The problem is I am getting an OutOfMemory Error since the file size is too large.

Answer 1

How about using a memory mapped file: FileChannel

From http://www.java-tips.org/java-se-tips/java.nio/how-to-create-a-memory-mapped-file-3.html:

try {
    File file = new File("filename");

    // Create a read-only memory-mapped file
    FileChannel roChannel = 
      new RandomAccessFile(file, "r").getChannel();

    ByteBuffer readonlybuffer = 
      roChannel.map(FileChannel.MapMode.READ_ONLY, 
0, (int)roChannel.size());

    // Create a read-write memory-mapped file
    FileChannel rwChannel = 
      new RandomAccessFile(file, "rw").getChannel();

    ByteBuffer writeonlybuffer= 
      rwChannel.map(FileChannel.MapMode.READ_WRITE, 
  0, (int)rwChannel.size());

    // Create a private (copy-on-write) memory-mapped file.
    // Any write to this channel results in a private 
    // copy of the data.
    FileChannel pvChannel = 
      new RandomAccessFile(file, "rw").getChannel();

    ByteBuffer privatebuffer = 
      roChannel.map(FileChannel.MapMode.READ_WRITE, 
  0, (int)rwChannel.size());

} catch (IOException e) {
}