Android中Rxjava实现三级缓存的两种方式

 /** * Created by wukewei on 16/6/20. */ public class BehaviorSubjectFragment extends BaseFragment { public static BehaviorSubjectFragment newInstance() { BehaviorSubjectFragment fragment = new BehaviorSubjectFragment(); return fragment; } String diskData = null; String networkData = "从服务器获取的数据"; BehaviorSubject cache; View mView; @Nullable @Override public View onCreateView(LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) { mView = inflater.inflate(R.layout.fragment_content, container, false); init(); return mView; } private void init() { mView.findViewById(R.id.get).setOnClickListener(new View.OnClickListener() { @Override public void onClick(View v) { subscriptionData(new Observer() { @Override public void onCompleted() { } @Override public void onError(Throwable e) { } @Override public void onNext(String s) { Log.d("onNext", s); } }); } }); mView.findViewById(R.id.memory).setOnClickListener(new View.OnClickListener() { @Override public void onClick(View v) { BehaviorSubjectFragment.this.cache = null; } }); mView.findViewById(R.id.memory_disk).setOnClickListener(new View.OnClickListener() { @Override public void onClick(View v) { BehaviorSubjectFragment.this.cache = null; BehaviorSubjectFragment.this.diskData = null; } }); } private void loadNewWork() { Observable o = Observable.just(networkData) .doOnNext(new Action1() { @Override public void call(String s) { BehaviorSubjectFragment.this.diskData = s; Log.d("写入磁盘", "写入磁盘"); } }); o.subscribe(new Action1() { @Override public void call(String s) { cache.onNext(s); } }, new Action1() { @Override public void call(Throwable throwable) { } }); } private Subscription subscriptionData(@NonNull Observer observer) { if (cache == null) { cache = BehaviorSubject.create(); Observable.create(new Observable.OnSubscribe() { @Override public void call(Subscriber subscriber) { String data = diskData; if (data == null) { Log.d("来自网络", "来自网络"); loadNewWork(); } else { Log.d("来自磁盘", "来自磁盘"); subscriber.onNext(data); } } }) .subscribeOn(Schedulers.io()) .subscribe(cache); } else { Log.d("来自内存", "来自内存"); } return cache.observeOn(AndroidSchedulers.mainThread()).subscribe(observer); } } 

 /** * Created by wukewei on 16/6/19. */ public interface ICache {  Observable get(String key, Class cls);  void put(String key, T t); } 

 /** * Created by wukewei on 16/6/19. */ public class MemoryCache implements ICache{ private LruCache mCache; public MemoryCache() { final int maxMemory = (int) Runtime.getRuntime().maxMemory(); final int cacheSize = maxMemory / 8; mCache = new LruCache(cacheSize) { @Override protected int sizeOf(String key, String value) { try { return value.getBytes("UTF-8").length; } catch (UnsupportedEncodingException e) { e.printStackTrace(); return value.getBytes().length; } } }; } @Override public  Observable get(final String key, final Class cls) { return Observable.create(new Observable.OnSubscribe() { @Override public void call(Subscriber subscriber) { String result = mCache.get(key); if (subscriber.isUnsubscribed()) { return; } if (TextUtils.isEmpty(result)) { subscriber.onNext(null); } else { T t = new Gson().fromJson(result, cls); subscriber.onNext(t); } subscriber.onCompleted(); } }); } @Override public  void put(String key, T t) { if (null != t) { mCache.put(key, new Gson().toJson(t)); } } public void clearMemory(String key) { mCache.remove(key); } } 

 /** * Created by wukewei on 16/6/19. */ public class DiskCache implements ICache{ private static final String NAME = ".db"; public static long OTHER_CACHE_TIME = 10 * 60 * 1000; public static long WIFI_CACHE_TIME = 30 * 60 * 1000; File fileDir; public DiskCache() { fileDir = CacheLoader.getApplication().getCacheDir(); } @Override public  Observable get(final String key, final Class cls) { return Observable.create(new Observable.OnSubscribe() { @Override public void call(Subscriber subscriber) { T t = (T) getDiskData1(key + NAME); if (subscriber.isUnsubscribed()) { return; } if (t == null) { subscriber.onNext(null); } else { subscriber.onNext(t); } subscriber.onCompleted(); } }) .subscribeOn(Schedulers.io()) .observeOn(AndroidSchedulers.mainThread()); } @Override public  void put(final String key, final T t) { Observable.create(new Observable.OnSubscribe() { @Override public void call(Subscriber subscriber) { boolean isSuccess = isSave(key + NAME, t); if (!subscriber.isUnsubscribed() && isSuccess) { subscriber.onNext(t); subscriber.onCompleted(); } } }) .subscribeOn(Schedulers.io()) .observeOn(AndroidSchedulers.mainThread()) .subscribe(); } /** * 保存数据 */ private  boolean isSave(String fileName, T t) { File file = new File(fileDir, fileName); ObjectOutputStream objectOut = null; boolean isSuccess = false; try { FileOutputStream out = new FileOutputStream(file); objectOut = new ObjectOutputStream(out); objectOut.writeObject(t); objectOut.flush(); isSuccess=true; } catch (IOException e) { Log.e("写入缓存错误",e.getMessage()); } catch (Exception e) { Log.e("写入缓存错误",e.getMessage()); } finally { closeSilently(objectOut); } return isSuccess; } /** * 获取保存的数据 */ private Object getDiskData1(String fileName) { File file = new File(fileDir, fileName); if (isCacheDataFailure(file)) { return null; } if (!file.exists()) { return null; } Object o = null; ObjectInputStream read = null; try { read = new ObjectInputStream(new FileInputStream(file)); o = read.readObject(); } catch (StreamCorruptedException e) { Log.e("读取错误", e.getMessage()); } catch (IOException e) { Log.e("读取错误", e.getMessage()); } catch (ClassNotFoundException e) { Log.e("错误", e.getMessage()); } finally { closeSilently(read); } return o; } private void closeSilently(Closeable closeable) { if (closeable != null) { try { closeable.close(); } catch (Exception ignored) { } } } /** * 判断缓存是否已经失效 */ private boolean isCacheDataFailure(File dataFile) { if (!dataFile.exists()) { return false; } long existTime = System.currentTimeMillis() - dataFile.lastModified(); boolean failure = false; if (NetWorkUtil.getNetworkType(CacheLoader.getApplication()) == NetWorkUtil.NETTYPE_WIFI) { failure = existTime > WIFI_CACHE_TIME ? true : false; } else { failure = existTime > OTHER_CACHE_TIME ? true : false; } return failure; } public void clearDisk(String key) { File file = new File(fileDir, key + NAME); if (file.exists()) file.delete(); } } 

 / ** * Created by wukewei on 16/6/19. */ public class CacheLoader { private static Application application; public static Application getApplication() { return application; } private ICache mMemoryCache, mDiskCache; private CacheLoader() { mMemoryCache = new MemoryCache(); mDiskCache = new DiskCache(); } private static CacheLoader loader; public static CacheLoader getInstance(Context context) { application = (Application) context.getApplicationContext(); if (loader == null) { synchronized (CacheLoader.class) { if (loader == null) { loader = new CacheLoader(); } } } return loader; } public  Observable asDataObservable(String key, Class cls, NetworkCache networkCache) { Observable observable = Observable.concat( memory(key, cls), disk(key, cls), network(key, cls, networkCache)) .first(new Func1() { @Override public Boolean call(T t) { return t != null; } }); return observable; } private  Observable memory(String key, Class cls) { return mMemoryCache.get(key, cls).doOnNext(new Action1() { @Override public void call(T t) { if (null != t) { Log.d("我是来自内存","我是来自内存"); } } }); } private  Observable disk(final String key, Class cls) { return mDiskCache.get(key, cls) .doOnNext(new Action1() { @Override public void call(T t) { if (null != t) { Log.d("我是来自磁盘","我是来自磁盘"); mMemoryCache.put(key, t); } } }); } private  Observable network(final String key, Class cls , NetworkCache networkCache) { return networkCache.get(key, cls) .doOnNext(new Action1() { @Override public void call(T t) { if (null != t) { Log.d("我是来自网络","我是来自网络"); mDiskCache.put(key, t); mMemoryCache.put(key, t); } } }); } public void clearMemory(String key) { ((MemoryCache)mMemoryCache).clearMemory(key); } public void clearMemoryDisk(String key) { ((MemoryCache)mMemoryCache).clearMemory(key); ((DiskCache)mDiskCache).clearDisk(key); } } 

 /** * Created by wukewei on 16/6/19. */ public abstract class NetworkCache { public abstract Observable get(String key, final Class cls); } 

 /** * Created by wukewei on 16/5/30. */ public class ItemPresenter extends BasePresenter implements ItemContract.Presenter { private static final String key = "new_list"; protected int pn = 1; protected void replacePn() { pn = 1; } private boolean isRefresh() { return pn == 1; } private NetworkCache networkCache; public ItemPresenter(Activity activity, ItemContract.View view) { super(activity, view); } @Override public void getListData(String type) { if (isRefresh()) mView.showLoading(); networkCache = new NetworkCache() { @Override public Observable get(String key, Class cls) { return mHotApi.getPopular(ItemPresenter.this.pn, Constants.PAGE_SIZE, type) .compose(SchedulersCompat.applyIoSchedulers()) .compose(RxResultHelper.handleResult()) .flatMap(populars -> { ListPopular popular = new ListPopular(populars); return Observable.just(popular); }); } }; Subscription subscription = CacheLoader.getInstance(mActivity) .asDataObservable(key + type + ItemPresenter.this.pn, ListPopular.class, networkCache) .map(listPopular -> listPopular.data) .subscribe(populars -> { mView.showContent(); if (isRefresh()) { if (populars.size() == 0) mView.showNotdata(); mView.addRefreshData(populars); } else { mView.addLoadMoreData(populars); } }, throwable -> { if (isRefresh()) mView.showError(ErrorHanding.handleError(throwable)); handleError(throwable); }); addSubscrebe(subscription); } }