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You replace the data for a database record by using Cursor.putCurrent().
import com.sleepycat.db.Cursor; import com.sleepycat.db.Database; import com.sleepycat.db.DatabaseEntry; import com.sleepycat.db.LockMode; import com.sleepycat.db.OperationStatus; ... Cursor cursor = null; Database myDatabase = null; try { ... // Database open omitted for brevity ... // Create DatabaseEntry objects // searchKey is some String. DatabaseEntry theKey = new DatabaseEntry(searchKey.getBytes("UTF-8")); DatabaseEntry theData = new DatabaseEntry(); // Open a cursor using a database handle cursor = myDatabase.openCursor(null, null); // Position the cursor. Ignoring the return value for clarity OperationStatus retVal = cursor.getSearchKey(theKey, theData, LockMode.DEFAULT); // Replacement data String replaceStr = "My replacement string"; DatabaseEntry replacementData = new DatabaseEntry(replaceStr.getBytes("UTF-8")); cursor.putCurrent(replacementData); } catch (Exception e) { // Exception handling goes here } finally { // Make sure to close the cursor cursor.close(); }
Note that you cannot change a record's key using this method; the key parameter is always ignored when you replace a record.
When replacing the data portion of a record, if you are replacing a record that is a member of a sorted duplicates set, then the replacement will be successful only if the new record sorts identically to the old record. This means that if you are replacing a record that is a member of a sorted duplicates set, and if you are using the default lexicographic sort, then the replacement will fail due to violating the sort order. However, if you provide a custom sort routine that, for example, sorts based on just a few bytes out of the data item, then potentially you can perform a direct replacement and still not violate the restrictions described here.
Under these circumstances, if you want to replace the data contained by a duplicate record, and you are not using a custom sort routine, then delete the record and create a new record with the desired key and data.