--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/org/dancres/blitz/entry/ExpiredLocatorImpl.java	Sat Mar 21 11:00:06 2009 +0000
@@ -0,0 +1,140 @@
+package org.dancres.blitz.entry;
+
+import java.io.IOException;
+
+import java.util.logging.Level;
+
+import com.sleepycat.je.Cursor;
+import com.sleepycat.je.DatabaseEntry;
+import com.sleepycat.je.DatabaseException;
+import com.sleepycat.je.OperationStatus;
+
+import org.dancres.blitz.oid.OID;
+import org.dancres.blitz.oid.OIDFactory;
+
+/**
+   TupleLocator implementation to be used on Lease tables. See LeaseTrackerImpl
+   for information on the database format.
+ */
+class ExpiredLocatorImpl implements TupleLocator {
+    private Cursor theCursor;
+    private boolean isFirst = true;
+
+    private DatabaseEntry theLeaseRecord;
+    private DatabaseEntry theLeaseBucket;
+
+    private long theScanTime;
+
+    /**
+       @param aCursor the cursor to use for iteration
+     */
+    ExpiredLocatorImpl(Cursor aCursor) {
+        theCursor = aCursor;
+        theScanTime = System.currentTimeMillis();
+        theLeaseBucket = new DatabaseEntry();
+    }
+
+    /**
+       Invoke this to load the next matching Tuple.
+
+       @return <code>true</code> if there was a tuple, <code>false</code>
+       otherwise
+     */
+    public boolean fetchNext() throws IOException {
+        /*
+          The cursor will have been initialised whilst we decided which
+          field was best to search on which means it will already be pointed
+          at the first record so we must handle this case specially.
+        */
+        if (isFirst) {
+            isFirst = false;
+
+            return loadNext();
+        } else {
+            return loadNextMove();
+        }
+    }
+
+    private boolean loadNextMove() throws IOException {
+        return loadNext(true);
+    }
+
+    private boolean loadNext() throws IOException {
+        return loadNext(false);
+    }
+
+    private boolean loadNext(boolean advance) throws IOException {
+        OperationStatus myResult;
+
+        try {
+            theLeaseRecord = new DatabaseEntry();
+
+            if (advance)
+                myResult = theCursor.getNextDup(theLeaseBucket, theLeaseRecord,
+                                                null);
+            else
+                myResult = theCursor.getFirst(theLeaseBucket, theLeaseRecord,
+                                                null);
+        } catch (DatabaseException aDbe) {
+            EntryStorage.theLogger.log(Level.SEVERE, "Got Dbe", aDbe);
+            throw new IOException("Dbe");
+        }
+
+        if ((myResult.equals(OperationStatus.NOTFOUND)) ||
+            (theScanTime <
+             LeaseRecordUtils.unpackExpiry(theLeaseRecord.getData()))) {
+            
+            if (myResult != OperationStatus.NOTFOUND)
+                // System.err.println("Exceeding Expiry: " +
+                //                    LeaseRecordUtils.unpackExpiry(theLeaseRecord.getData()));
+
+            // Try for the next non-dupe
+            theLeaseRecord = new DatabaseEntry();
+
+            try {
+                // System.err.println("Skipping to next bucket");
+
+                myResult =
+                    theCursor.getNextNoDup(theLeaseBucket, theLeaseRecord, null);
+
+                if (myResult.equals(OperationStatus.SUCCESS))
+                    return true;
+            } catch (DatabaseException aDbe) {
+                EntryStorage.theLogger.log(Level.SEVERE, "Got Dbe", aDbe);
+                throw new IOException("Dbe");
+            }
+
+            return false;
+        } else {
+            // System.err.println("Maybe expiring one: " +
+            //                    LeaseRecordUtils.unpackExpiry(theLeaseRecord.getData()));
+            return true;
+        }
+    }
+
+    /**
+       @return the OID of the tuple just fetched with
+       <code>fetchNext</code>
+     */
+    public OID getOID() {
+        OID myResult =
+            OIDFactory.newOID(
+                LeaseRecordUtils.unpackId(theLeaseRecord.getData()));
+
+        // System.err.println("Time is up for: " + myResult);
+
+        return myResult;
+    }
+
+    /**
+       When you've finished with the TupleLocator instance, call release.
+     */
+    public void release() throws IOException {
+        try {
+            theCursor.close();
+        } catch (DatabaseException aDbe) {
+            EntryStorage.theLogger.log(Level.SEVERE, "Got Dbe", aDbe);
+            throw new IOException("Dbe");
+        }
+    }
+}