RandomAccessFile(String name, String mode)
close()
read(byte[] b)
write(byte[] b)
seek(long pos)
// ADT for buffer pools using the message-passing style
public interface BufferPoolADT {
// Copy "sz" bytes from "space" to position "pos" in the buffered storage
public void insert(byte[] space, int sz, int pos);
// Copy "sz" bytes from position "pos" of the buffered storage to "space"
public void getbytes(byte[] space, int sz, int pos);
}
// ADT for buffer pools using the buffer-passing style
public interface BufferPoolADT {
// Return pointer to the requested block
public byte[] getblock(int block);
// Set the dirty bit for the buffer holding "block"
public void dirtyblock(int block);
// Tell the size of a buffer
public int blocksize();
};
// Improved ADT for buffer pools using the buffer-passing style.
// Most user functionality is in the buffer class, not the buffer pool itself.
// A single buffer in the buffer pool
public interface BufferADT {
// Read the associated block from disk (if necessary) and return a
// pointer to the data
public byte[] readBlock();
// Return a pointer to the buffer's data array (without reading from disk)
public byte[] getDataPointer();
// Flag buffer's contents as having changed, so that flushing the
// block will write it back to disk
public void markDirty();
// Release the block's access to this buffer. Further accesses to
// this buffer are illegal
public void releaseBuffer();
}
public interface BufferPoolADT {
// Relate a block to a buffer, returning a pointer to a buffer object
Buffer acquireBuffer(int block);
}
If the next key in the file is greater than the last value output, then
- Replace the root with this key
else
- Replace the root with the last key in the array
Add the next record in the file to a new heap (actually, stick it at the end of the array).