/**
* Creates an index of the specified type for the specified field. A unique ID is assigned to this
* index, and its information is stored in the idxcat table.
*
* @param idxName the name of the index
* @param tblName the name of the indexed table
* @param fldName the name of the indexed field
* @param idxType the index type of the indexed field
* @param tx the calling transaction
*/
public void createIndex(
String idxName, String tblName, String fldName, int idxType, Transaction tx) {
RecordFile rf = ti.open(tx);
rf.insert();
rf.setVal(ICAT_IDXNAME, new VarcharConstant(idxName));
rf.setVal(ICAT_TBLNAME, new VarcharConstant(tblName));
rf.setVal(ICAT_FLDNAME, new VarcharConstant(fldName));
rf.setVal(ICAT_IDXTYPE, new IntegerConstant(idxType));
rf.close();
}
/** Synchronizes the indicated blocks with the owner. */
private void synchronizeBlocks(Iterable<BlockIo> blocks, boolean fromCore) throws IOException {
// write block vector elements to the data file.
for (BlockIo cur : blocks) {
owner.synch(cur);
if (fromCore) {
cur.decrementTransactionCount();
if (!cur.isInTransaction()) {
owner.releaseFromTransaction(cur, true);
}
}
}
}
/** Synchs in-core transactions to data file and opens a fresh log */
private void synchronizeLogFromMemory() throws IOException {
close();
TreeSet<BlockIo> blockList = new TreeSet<BlockIo>(new BlockIoComparator());
int numBlocks = 0;
int writtenBlocks = 0;
for (int i = 0; i < _maxTxns; i++) {
if (txns[i] == null) continue;
// Add each block to the blockList, replacing the old copy of this
// block if necessary, thus avoiding writing the same block twice
for (Iterator<BlockIo> k = txns[i].iterator(); k.hasNext(); ) {
BlockIo block = k.next();
if (blockList.contains(block)) {
block.decrementTransactionCount();
} else {
writtenBlocks++;
boolean result = blockList.add(block);
}
numBlocks++;
}
txns[i] = null;
}
// Write the blocks from the blockList to disk
synchronizeBlocks(blockList, true);
owner.sync();
open();
}
/** Discards the indicated blocks and notify the owner. */
private void discardBlocks(ArrayList<BlockIo> blocks) throws IOException {
for (BlockIo cur : blocks) {
cur.decrementTransactionCount();
if (!cur.isInTransaction()) {
owner.releaseFromTransaction(cur, false);
}
}
}
/**
* Returns a map containing the index info for all indexes on the specified table.
*
* @param tblName the name of the table
* @param tx the calling transaction
* @return a map of IndexInfo objects, keyed by their field names
*/
public Map<String, IndexInfo> getIndexInfo(String tblName, Transaction tx) {
Map<String, IndexInfo> result = new HashMap<String, IndexInfo>();
RecordFile rf = ti.open(tx);
rf.beforeFirst();
while (rf.next())
if (((String) rf.getVal(ICAT_TBLNAME).asJavaVal()).equals(tblName)) {
String idxname = (String) rf.getVal(ICAT_IDXNAME).asJavaVal();
String fldname = (String) rf.getVal(ICAT_FLDNAME).asJavaVal();
int idxtype = (Integer) rf.getVal(ICAT_IDXTYPE).asJavaVal();
IndexInfo ii = new IndexInfo(idxname, tblName, fldname, idxtype);
result.put(fldname, ii);
}
rf.close();
return result;
}
/** Startup recovery on all files */
private void recover() throws IOException {
String logName = makeLogName();
File logFile = new File(logName);
if (!logFile.exists()) return;
if (logFile.length() == 0) {
logFile.delete();
return;
}
FileInputStream fis = new FileInputStream(logFile);
DataInputStream ois = new DataInputStream(new BufferedInputStream(fis));
try {
if (ois.readShort() != Magic.LOGFILE_HEADER) throw new Error("Bad magic on log file");
} catch (IOException e) {
// corrupted/empty logfile
logFile.delete();
return;
}
while (true) {
ArrayList<BlockIo> blocks = null;
try {
blocks = (ArrayList<BlockIo>) Serialization.readObject(ois);
} catch (ClassNotFoundException e) {
throw new Error("Unexcepted exception: " + e);
} catch (IOException e) {
// corrupted logfile, ignore rest of transactions
break;
}
synchronizeBlocks(blocks, false);
// ObjectInputStream must match exactly each
// ObjectOutputStream created during writes
// try {
ois = new DataInputStream(fis);
// } catch (IOException e) {
// // corrupted logfile, ignore rest of transactions
// break;
// }
}
owner.sync();
fis.close();
logFile.delete();
}
/** Builds logfile name */
private String makeLogName() {
return owner.getFileName() + extension;
}