localmodel.java

这个范例程序演示了利用j2me技术开发无线服务器支持的应用。这是一个电影票订购程序

     */
    public Preferences getPreferences() throws ApplicationException {
        if (preferences == null) {
            IndexEntry indexEntry = rmsAdapter.getIndexEntry("*", 
                    IndexEntry.TYPE_PREFERENCES, IndexEntry.MODE_ANY);

            if (indexEntry != null) {
                preferences = 
                    rmsAdapter.loadPreferences(indexEntry.getRecordId());
            } else {
                preferences = new Preferences();

                int recordId = 
                    rmsAdapter.storePreferences(preferences, 
                                                indexEntry != null 
                                                ? indexEntry.getRecordId() 
                                                : -1);

                indexEntry = new IndexEntry(recordId, 
                                            IndexEntry.TYPE_PREFERENCES, "*", 
                                            IndexEntry.MODE_PERSISTING);

                rmsAdapter.addIndexEntry(indexEntry);
            } 
        } 

        return preferences;
    } 

    // public void setPreferences() throws ApplicationException {
    public void setPreferences(Preferences preferences) 
            throws ApplicationException {
        this.preferences.copy(preferences);

        IndexEntry indexEntry = rmsAdapter.getIndexEntry("*", 
                IndexEntry.TYPE_PREFERENCES, IndexEntry.MODE_ANY);
        int recordId = rmsAdapter.storePreferences(preferences, 
                                                   indexEntry != null 
                                                   ? indexEntry.getRecordId() 
                                                   : -1);

        if (indexEntry == null) {
            indexEntry = new IndexEntry(recordId, 
                                        IndexEntry.TYPE_PREFERENCES, "*", 
                                        IndexEntry.MODE_PERSISTING);

            rmsAdapter.addIndexEntry(indexEntry);
        } 

        return;
    } 

    public IndexedResourceBundle getResourceBundle(String baseName) 
            throws ApplicationException {
        try {
            IndexEntry indexEntry = rmsAdapter.getIndexEntry(baseName, 
                    IndexEntry.TYPE_RESOURCE_BUNDLE, IndexEntry.MODE_ANY);

            if (indexEntry != null) {
                return rmsAdapter.loadResourceBundle(indexEntry.getRecordId());
            } 
        } catch (ApplicationException ae) {}

        return null;
    } 

    public void setResourceBundle(String baseName, IndexedResourceBundle bundle) 
            throws ApplicationException {
        IndexEntry indexEntry = rmsAdapter.getIndexEntry(baseName, 
                IndexEntry.TYPE_RESOURCE_BUNDLE, IndexEntry.MODE_ANY);
        int recordId = rmsAdapter.storeResourceBundle(bundle, 
                indexEntry != null ? indexEntry.getRecordId() : -1);

        if (indexEntry == null) {
            indexEntry = new IndexEntry(recordId, 
                                        IndexEntry.TYPE_RESOURCE_BUNDLE, 
                                        baseName, IndexEntry.MODE_PERSISTING);

            rmsAdapter.addIndexEntry(indexEntry);
        } 

        return;
    } 

    public void setMovieRating(MovieRating movieRating) 
            throws ApplicationException {
        IndexEntry indexEntry = 
            rmsAdapter.getIndexEntry(movieRating.getPrimaryKey(), 
                                     IndexEntry.TYPE_MOVIE_RATING, 
                                     IndexEntry.MODE_ANY);
        int recordId = rmsAdapter.storeMovieRating(movieRating, 
                                                   indexEntry != null 
                                                   ? indexEntry.getRecordId() 
                                                   : -1);

        if (indexEntry == null) {
            indexEntry = new IndexEntry(recordId, 
                                        IndexEntry.TYPE_MOVIE_RATING, 
                                        movieRating.getPrimaryKey(), 
                                        IndexEntry.MODE_PERSISTING);

            rmsAdapter.addIndexEntry(indexEntry);
            persistRatedMovie(movieRating.getMovie());
        } 

        return;
    } 

    public void addMovieRating(MovieRating movieRating) 
            throws ApplicationException {
        IndexEntry indexEntry = 
            rmsAdapter.getIndexEntry(movieRating.getPrimaryKey(), 
                                     IndexEntry.TYPE_MOVIE_RATING, 
                                     IndexEntry.MODE_ANY);
        int recordId = -1;

        if (indexEntry != null) {
            recordId = indexEntry.getRecordId();

            MovieRating rating = rmsAdapter.loadMovieRating(recordId);

            rating.setLastViewingDate(movieRating.getLastViewingDate());

            movieRating = rating;
        } 

        recordId = rmsAdapter.storeMovieRating(movieRating, recordId);

        if (indexEntry == null) {
            indexEntry = new IndexEntry(recordId, 
                                        IndexEntry.TYPE_MOVIE_RATING, 
                                        movieRating.getPrimaryKey(), 
                                        IndexEntry.MODE_PERSISTING);

            rmsAdapter.addIndexEntry(indexEntry);
            persistRatedMovie(movieRating.getMovie());
        } 

        return;
    } 

    public void deleteMovieRating(String movieRatingKey) 
            throws ApplicationException {
        IndexEntry indexEntry = rmsAdapter.getIndexEntry(movieRatingKey, 
                IndexEntry.TYPE_MOVIE_RATING, IndexEntry.MODE_ANY);

        if (indexEntry != null) {
            MovieRating movieRating = 
                rmsAdapter.loadMovieRating(indexEntry.getRecordId());

            movieRating.setModificationStatus(Synchronizable.STATUS_DELETED);
            rmsAdapter.storeMovieRating(movieRating, 
                                        indexEntry.getRecordId());
        } 

        return;
    } 

    public void purgeMovieRating(String movieRatingKey) 
            throws ApplicationException {
        IndexEntry indexEntry = rmsAdapter.getIndexEntry(movieRatingKey, 
                IndexEntry.TYPE_MOVIE_RATING, IndexEntry.MODE_ANY);

        if (indexEntry != null) {
            rmsAdapter.deleteMovieRating(indexEntry.getRecordId());
            rmsAdapter.deleteIndexEntry(indexEntry.getKey(), 
                                        indexEntry.getType());
        } 

        return;
    } 

    public MovieRating[] getMovieRatings() throws ApplicationException {
        IndexEntry[] indexEntries = 
            rmsAdapter.getIndexEntries(IndexEntry.TYPE_MOVIE_RATING, 
                                       IndexEntry.MODE_ANY);
        MovieRating[] movieRatings = new MovieRating[indexEntries.length];

        for (int i = 0; i < indexEntries.length; i++) {
            movieRatings[i] = 
                rmsAdapter.loadMovieRating(indexEntries[i].getRecordId());
        } 

        return movieRatings;
    } 

    private void persistRatedMovie(Movie movie) throws ApplicationException {
        IndexEntry indexEntry = 
            rmsAdapter.getIndexEntry(movie.getPrimaryKey(), 
                                     IndexEntry.TYPE_MOVIE, 
                                     IndexEntry.MODE_ANY);

        if (indexEntry == null) {
            int recordId = rmsAdapter.storeMovie(movie, -1);

            indexEntry = new IndexEntry(recordId, IndexEntry.TYPE_MOVIE, 
                                        movie.getPrimaryKey(), 
                                        IndexEntry.MODE_PERSISTING);

            rmsAdapter.addIndexEntry(indexEntry);
        } else if (indexEntry.getMode() != IndexEntry.MODE_PERSISTING) {
            // since persisting: overwrite caching entries
            indexEntry = new IndexEntry(indexEntry.getRecordId(), 
                                        indexEntry.getType(), 
                                        indexEntry.getKey(), 
                                        IndexEntry.MODE_PERSISTING);

            rmsAdapter.addIndexEntry(indexEntry);
        } 

        return;
    } 

    public void setMovieRatingSyncAnchor(SyncAnchor syncAnchor) 
            throws ApplicationException {
        IndexEntry indexEntry = rmsAdapter.getIndexEntry("MOVIE_RATINGS", 
                IndexEntry.TYPE_SYNC_ANCHOR, IndexEntry.MODE_ANY);
        int recordId = rmsAdapter.storeSyncAnchor(syncAnchor, 
                                                  indexEntry != null 
                                                  ? indexEntry.getRecordId() 
                                                  : -1);

        if (indexEntry == null) {
            indexEntry = new IndexEntry(recordId, 
                                        IndexEntry.TYPE_SYNC_ANCHOR, 
                                        "MOVIE_RATINGS", 
                                        IndexEntry.MODE_PERSISTING);

            rmsAdapter.addIndexEntry(indexEntry);
        } 

        return;
    } 

    public SyncAnchor getMovieRatingSyncAnchor() throws ApplicationException {
        IndexEntry indexEntry = rmsAdapter.getIndexEntry("MOVIE_RATINGS", 
                IndexEntry.TYPE_SYNC_ANCHOR, IndexEntry.MODE_ANY);

        return indexEntry != null 
               ? rmsAdapter.loadSyncAnchor(indexEntry.getRecordId()) : null;
    } 

}