Unit Testing Workshop Exercises Interfaces

DBConnection.java

public interface DBConnection {

    /**
     * Commits a student to this connection.
     * 
     * @param student the student to be committed.
     * @return <code>0</code> if committed successfully, <code>-1</code> otherwise.
     */
    int commitStudent(Student student);
}

StudentDB.java

public interface StudentDB {

    /**
     * Adds a student to the database.
     *
     * Once a new student is added to the database, the database
     * will be marked as dirty.
     *
     * @param student the student to be added
     */
    void addStudent(Student student);


    /**
     * Removes a student to the database.
     *
     * Once a student is removed from the database, the database
     * will be marked as dirty.
     *
     * @param student the student to be removed
     */
    void removeStudent(Student student);

    /**
     * Returns the count of unique students in the database.
     *
     * @return a positive integer with the count of unique students in the database
     */
    int countStudents();

    /**
     * Commits all the student to a given connection.
     * Commits only when the database is set to dirty.
     *
     * @param connection to which all the students will be committed.
     * @return <code>true</code> if all the students where committed successfully,
     *         <code>false</code> otherwise.
     */
    boolean commit(DBConnection connection);

    /**
     * Is the database dirty with any uncommitted changes.
     * @return <code>true</code> if there are any uncommitted changes, <code>false</code> otherwise.
     */
    boolean isDirty();

}