在调用close（）之前，此Realm实例已经关闭

Question

尝试执行以下代码时，我总是收到异常消息;

  

java.lang.IllegalStateException：此Realm实例已被关闭，使其无法使用。

但是如果我注释掉database.close（）调用那么它工作正常。可能是什么原因？

Observable.defer(() -> Observable.create((ObservableOnSubscribe<String>) cacheEmitter -> {

                Realm database = Realm.getDefaultInstance();

                database.executeTransaction(realm -> {

                    RealmResults<ResponseCache> cache = realm.where(ResponseCache.class).findAll();
                    ResponseCache cacheData = new ResponseCache(null, "");
                    for(ResponseCache resCache : cache) {

                        if(resCache.getCategoryId().equals(searchType)) {
                            cacheData = new ResponseCache(resCache);
                            break;
                        }
                    }

                    String cacheResData = cacheData.getSearchResponse();
                    database.close();
                    cacheEmitter.onNext(cacheResData);
                });

            }))

Answer 1

应该是

try(Realm database = Realm.getDefaultInstance()) {
    database.executeTransaction(realm -> {
        RealmResults<ResponseCache> cache = realm.where(ResponseCache.class).findAll();
        ResponseCache cacheData = new ResponseCache(null, "");
        for(ResponseCache resCache : cache) {
            if(resCache.getCategoryId().equals(searchType)) {
                cacheData = new ResponseCache(resCache);
                break;
            }
        }

        String cacheResData = cacheData.getSearchResponse();
        cacheEmitter.onNext(cacheResData);
    });
}