/**
* Searches the directory for a data page with enough free space to store a record of the given
* size. If no suitable page is found, this creates a new data page.
*/
protected PageId getAvailPage(int reclen) {
for (int i = 0; i < pages.size(); i++) {
PageId pid = pages.get(i);
Page page = new Page();
global.Minibase.BufferManager.pinPage(pid, page, false);
HFPage hfpage = new HFPage();
hfpage.copyPage(page);
if (hfpage.getFreeSpace() >= reclen) {
global.Minibase.BufferManager.unpinPage(pid, true);
return pid;
}
global.Minibase.BufferManager.unpinPage(pid, false);
}
Page page = new Page();
PageId pid = global.Minibase.BufferManager.newPage(page, 1);
HFPage hfpage = new HFPage(page);
// initialize HFPage
hfpage.setCurPage(pid);
pages.add(pid);
pids.add(pid.pid);
current.setNextPage(pid);
hfpage.setPrevPage(current.getCurPage());
current = hfpage;
global.Minibase.BufferManager.unpinPage(pid, true);
return pid;
}
/**
* Inserts a new record into the file and returns its RID.
*
* @throws IllegalArgumentException if the record is too large
*/
public RID insertRecord(byte[] record) throws IllegalArgumentException, ChainException {
if (record.length > GlobalConst.MAX_TUPSIZE)
throw new IllegalArgumentException("the record's size is too large");
for (int i = 0; i < pages.size(); i++) {
PageId pid = pages.get(i);
Page page = new Page();
global.Minibase.BufferManager.pinPage(pid, page, false);
HFPage hfpage = new HFPage(page);
hfpage.setCurPage(pid);
hfpage.setData(page.getData());
if (hfpage.getFreeSpace() > record.length) {
RID rid = hfpage.insertRecord(record);
recordNumber++;
global.Minibase.BufferManager.unpinPage(pid, true);
return rid;
}
global.Minibase.BufferManager.unpinPage(pid, false);
}
Page page = new Page();
PageId pid = global.Minibase.BufferManager.newPage(page, 1);
HFPage hfpage = new HFPage(page);
// initialize HFPage
hfpage.initDefaults();
hfpage.setCurPage(pid);
// hfpage.print();
RID rid = hfpage.insertRecord(record);
pages.add(pid);
pids.add(pid.pid);
hfpage.setNextPage(pid);
hfpage.setPrevPage(current.getCurPage());
current = hfpage;
global.Minibase.BufferManager.unpinPage(pid, true);
// hfpage.print();
// System.out.println ("The PID is "+pid);
recordNumber++;
return rid;
}