[컴][자바] singleton 예제

java 에서 싱글턴 구현하기, singleton example, 싱글튼 예제, Java singleton example, how to implement

Singleton

public class FavoriteListAdapter extends BaseAdapter{

	ArrayList<ChartItem> favoriteList;
	private volatile static FavoriteListAdapter instance;
	
	/** Returns singleton class instance */
	public static FavoriteListAdapter getInstance() {
		if (instance == null) {
			synchronized (FavoriteListAdapter.class) {
				if (instance == null) {
					instance = new FavoriteListAdapter();
				}
			}
		}
		return instance;
	}
	
	protected FavoriteListAdapter() {
	}
	
	public synchronized void init(Context context){
		
		// namh
		mDiskCache = new DiskLruImageCache(context, "muchart", 
										DISK_CACHE_SIZE,
										CompressFormat.JPEG,
										70);

		mExecutorService = Executors.newFixedThreadPool(5);
		mEmptyImage = getRoundedCornerBitmap(
			BitmapFactory.decodeResource(context.getResources(), R.drawable.noimage)
		);
	}
	...
}

MainActivity.java

@Override
    public void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
        
		// Sigleton ImageLoader
		ImageLoader.getInstance().init(this);