在RxJava中处理检查到的异常

Observable.just(1, 2, 3)
    .map(num -> {
        if (num == 2) {
            throw new Exception("Something went wrong");
        }
        return num;
    })
    .onErrorReturn(throwable -> -1) // 返回默认值 -1
    .subscribe(System.out::println);

Observable.just(1, 2, 3)
    .map(num -> {
        if (num == 2) {
            throw new Exception("Something went wrong");
        }
        return num;
    })
    .onErrorResumeNext(Observable.just(4, 5, 6)) // 切换到备用的Observable
    .subscribe(System.out::println);

Observable.just(1, 2, 3)
    .map(num -> {
        if (num == 2) {
            throw new Exception("Something went wrong");
        }
        return num;
    })
    .retry(2) // 最多重试2次
    .subscribe(System.out::println);