### Question:
RemitStoreOnSQLite implements RemitSyncExecutor.RemitAgent, DownloadStore { @Override public boolean isFileDirty(int id) { return onSQLiteWrapper.isFileDirty(id); } RemitStoreOnSQLite(@NonNull BreakpointStoreOnSQLite sqlite);   RemitStoreOnSQLite(@NonNull RemitSyncToDBHelper helper, @NonNull BreakpointStoreOnSQLite sqlite,
                       @NonNull DownloadStore sqliteCache,
                       @NonNull BreakpointSQLiteHelper sqLiteHelper); @Nullable @Override BreakpointInfo get(int id); @NonNull @Override BreakpointInfo createAndInsert(@NonNull DownloadTask task); @Override void onTaskStart(int id); @Override void onSyncToFilesystemSuccess(@NonNull BreakpointInfo info, int blockIndex,
                                                    long increaseLength); @Override boolean update(@NonNull BreakpointInfo info); @Override void onTaskEnd(int id, @NonNull EndCause cause, @Nullable Exception exception); @Nullable @Override BreakpointInfo getAfterCompleted(int id); @Override boolean markFileDirty(int id); @Override boolean markFileClear(int id); @Override void remove(int id); @Override int findOrCreateId(@NonNull DownloadTask task); @Nullable @Override BreakpointInfo findAnotherInfoFromCompare(@NonNull DownloadTask task,
                                                     @NonNull BreakpointInfo ignored); @Override boolean isOnlyMemoryCache(); @Override boolean isFileDirty(int id); @Nullable @Override String getResponseFilename(String url); @Override void syncCacheToDB(List<Integer> idList); @Override void syncCacheToDB(int id); @Override void removeInfo(int id); static void setRemitToDBDelayMillis(int delayMillis);  }### Answer:
@Test public void isFileDirty() { doReturn(true).when(storeOnSQLite).isFileDirty(1); assertThat(store.isFileDirty(1)).isTrue(); doReturn(false).when(storeOnSQLite).isFileDirty(1); assertThat(store.isFileDirty(1)).isFalse(); }