Interface SongOperation

All Known Subinterfaces:
AndPredicateSemantics, FalsePredicateSemantics, GetFieldAsStringArraySemantics, GetFieldAsStringSemantics, GetFirstLineSemantics, NopSemantics, NotPredicateSemantics, OrPredicateSemantics, PredicateFilterSemantics, PredicateSemantics, SearchBodyPredicateSemantics, SearchFieldPredicateSemantics, TruePredicateSemantics, ValueFilterSemantics
All Known Implementing Classes:
AndPredicateSemantics.DefaultImplementation, FalsePredicateSemantics.DefaultImplementation, GetFieldAsStringArraySemantics.DefaultImplementation, GetFieldAsStringSemantics.DefaultImplementation, GetFirstLineSemantics.DefaultImplementation, NopSemantics.DefaultImplementation, NotPredicateSemantics.DefaultImplementation, OrPredicateSemantics.DefaultImplementation, PredicateFilterSemantics.DefaultImplementation, SearchBodyPredicateSemantics.DefaultImplementation, SearchFieldPredicateSemantics.DefaultImplementation, TruePredicateSemantics.DefaultImplementation, ValueFilterSemantics.DefaultImplementation

public interface SongOperation

An operation to perform on SongIDResultSets. This interface merely specifies that this object implements an operation. Most operation also implement a particular OpSemantics interface to indicate to the database implementation the kind of operation, so the database can substitute an optimized implementation if it so chooses.

Method Summary
 boolean equals(Object obj)
          The equals method should return true if the given object is a SongOperation with the same semantics as this one.
 void perform(SongIDResultSet resultSet)
          Performs the operation on the given result set.

Method Detail


public void perform(SongIDResultSet resultSet)
             throws SongDatabaseFailedException
Performs the operation on the given result set.

resultSet - the SongIDResultSet
SongDatabaseFailedException - Catch-all exception for database-related problems. This will often have a cause exception, which may be exceptions like IOException or SQLException.


public boolean equals(Object obj)
The equals method should return true if the given object is a SongOperation with the same semantics as this one. (i.e. it would perform the same operation.) This may be used to optimize performance. It is always safe to return false from this method, if the semantics of the given object cannot be determined. (This is similar to the equals method in java.util.Comparator.) As a corollary, it is safe just to fall back on the default implementation inherited from java.lang.Object.

obj - object to test
true if the object is equal