一、take语法

  public Observable<Integer> getRxJavaCreateExampleData() {
        return Observable.create(new ObservableOnSubscribe<Integer>() {
            @Override
            public void subscribe(ObservableEmitter<Integer> emitter) {
                LogUtils.debug(TAG, "getRxJavaCreateExampleData---:" + Thread.currentThread().getName() + "--:" + 1);
                emitter.onNext(1);

                LogUtils.debug(TAG, "getRxJavaCreateExampleData---:" + Thread.currentThread().getName() + "--:" + 2);
                emitter.onNext(2);

                LogUtils.debug(TAG, "getRxJavaCreateExampleData---:" + Thread.currentThread().getName() + "--:" + 3);
                emitter.onNext(3);
                emitter.onComplete();
                LogUtils.debug(TAG, "getRxJavaCreateExampleData---:" + Thread.currentThread().getName() + "--:" + 4);
                emitter.onNext(4);

            }
        });
    }
   public void rxJavaTakeExample() {
        Disposable disposable = model.getRxJavaCreateExampleData()
                .subscribeOn(Schedulers.io())
                .unsubscribeOn(Schedulers.io())
                .take(2)
                .observeOn(AndroidSchedulers.mainThread())
                .subscribe(new Consumer<Integer>() {
                    @Override
                    public void accept(Integer integer) throws Exception {
                        LogUtils.error(TAG, "rxJavaTakeExample--:" + Thread.currentThread().getName() + "-Consumer-:" + integer);
                    }
                });
        compositeDisposable.add(disposable);
    }

日志

08-18 14:36:56.835 22993-23746/com.example.zhang D/MainModel: getRxJavaCreateExampleData---:RxCachedThreadScheduler-1--:1
    getRxJavaCreateExampleData---:RxCachedThreadScheduler-1--:2
08-18 14:36:56.837 22993-23746/com.example.zhang D/MainModel: getRxJavaCreateExampleData---:RxCachedThreadScheduler-1--:3
    getRxJavaCreateExampleData---:RxCachedThreadScheduler-1--:4
08-18 14:36:56.837 22993-22993/com.example.zhang E/MainPresenter: rxJavaTakeExample--:main-Consumer-:1
    rxJavaTakeExample--:main-Consumer-:2

总结

1、take(long count) count 能接收的最多count个数据