/**
* Writes this messages body to the given output stream. This method may only be called once
* during the lifetime of this message.
*
* @param os an output stream
* @exception IOException if there is an I/O error
*/
public void write(OutputStream os) throws IOException {
Assert.isTrue(!inputRead);
Assert.isTrue(!hasInputStream);
int bytesRead = 0;
int totalBytesRead = 0;
byte[] buffer = bufferPool.getBuffer();
long contentLength = getContentLength();
try {
while (bytesRead != -1 && (contentLength == -1 || contentLength > totalBytesRead)) {
if (contentLength == -1) {
bytesRead = is.read(buffer);
} else {
bytesRead =
is.read(buffer, 0, (int) Math.min(buffer.length, contentLength - totalBytesRead));
}
if (bytesRead == -1) {
if (contentLength >= 0) {
throw new IOException(Policy.bind("exception.unexpectedEndStream")); // $NON-NLS-1$
}
} else {
totalBytesRead += bytesRead;
os.write(buffer, 0, bytesRead);
}
}
} finally {
bufferPool.putBuffer(buffer);
inputRead = true;
}
}
// see DbFile.java for javadocs
public ArrayList<Page> insertTuple(TransactionId tid, Tuple t)
throws DbException, IOException, TransactionAbortedException {
// some code goes here
BufferPool bp = Database.getBufferPool();
int id = getId(), i, slots;
ArrayList<Page> retlist = new ArrayList<Page>();
PageId pid = null;
HeapPage p = null;
for (i = 0; i < numPages(); i++) {
pid = new HeapPageId(id, i);
p = (HeapPage) bp.getPage(tid, pid, Permissions.READ_WRITE);
slots = p.getNumEmptySlots();
if (slots > 0) {
p.insertTuple(t);
retlist.add(p);
return retlist;
}
}
// create new page and add tuple to it
pid = new HeapPageId(id, i);
raf.setLength(raf.length() + BufferPool.PAGE_SIZE);
p = (HeapPage) bp.getPage(tid, pid, Permissions.READ_WRITE);
p.insertTuple(t);
retlist.add(p);
return retlist;
}
// see DbFile.java for javadocs
public Page deleteTuple(TransactionId tid, Tuple t)
throws DbException, TransactionAbortedException {
// some code goes here
BufferPool bp = Database.getBufferPool();
RecordId rid = t.getRecordId();
if (rid == null) {
throw new DbException("Tuple is not a member of this file");
}
HeapPage p = (HeapPage) bp.getPage(tid, rid.getPageId(), Permissions.READ_WRITE);
p.deleteTuple(t);
return p;
}
public Tuple getNext() throws NoSuchElementException, TransactionAbortedException {
try {
Tuple tuple = new Tuple(td);
for (int i = 0; i < td.numFields(); i++) {
IntField intf = IntField.createIntField(in.readInt());
tuple.setField(i, intf);
}
return tuple;
} catch (EOFException eof) {
throw new NoSuchElementException(eof.getMessage());
} catch (Exception e) {
e.printStackTrace();
BufferPool.Instance().abortTransaction(tid);
closeConnection();
throw new TransactionAbortedException(e);
}
}