J2ME in a Nutshell

Name

RecordFilter

Synopsis

This interface selects which RecordStore records should be included in a RecordEnumeration. It consists of a single method, matches(), which examines the contents of a record and returns true if the record should be included, or false if it should not.

A typical implementation of this method wraps the incoming record with a ByteArrayInputStream and a DataInputStream so that the contents of the record can be accessed as a set of fields. For example, to construct a filter that would include only records whose first field (assumed to be a String) starts with the letter S, first create a DataInputStream from the candidate:

DataInputStream dis = new DataInputStream(new ByteArrayInputStream(candidate));

Then, extract the field to be compared using the DataInputStream readUTF() method and test its first character:

return dis.readUTF().startsWith("S");

public interface RecordFilter {  
// Public Instance Methods
   public abstract boolean matches(byte[] candidate);  
}

Passed To

RecordStore.enumerateRecords()