先看我的代码：（用于测试的）

        People people1 = new People("join","21");
        People people2 = new People("jane","29");

        Observable.just(people1,people2)

                .subscribeOn(AndroidSchedulers.mainThread())    //在主线程上把 UI 初始化
                .doOnNext(people -> {
                    num  = 0;
                    show.setText(String.valueOf(num));
                })

                .repeat(4,Schedulers.newThread())  //在新线程上重复发送2次

                .observeOn(AndroidSchedulers.mainThread())    //在主线程上观测
                .subscribe(peoples1 -> {
                    String s = people1.toString();
                    num++;
                    show.setText(String.valueOf(num));
                    Log.e("---",s);
                });

这里，just先发射第一个 People：people1，之后再发射people2.
但是呢，Logcat如下：

06-29 20:25:20.251 32688-32688/demo.chestnut.com.test E/---: People{name='join', age='21'}
06-29 20:25:20.251 32688-32688/demo.chestnut.com.test E/---: People{name='join', age='21'}
06-29 20:25:20.281 32688-32688/demo.chestnut.com.test E/---: People{name='join', age='21'}
06-29 20:25:20.281 32688-32688/demo.chestnut.com.test E/---: People{name='join', age='21'}
06-29 20:25:20.287 32688-32688/demo.chestnut.com.test E/---: People{name='join', age='21'}
06-29 20:25:20.287 32688-32688/demo.chestnut.com.test E/---: People{name='join', age='21'}
06-29 20:25:20.302 32688-32688/demo.chestnut.com.test E/---: People{name='join', age='21'}
06-29 20:25:20.302 32688-32688/demo.chestnut.com.test E/---: People{name='join', age='21'}

这里打印了8次的 people1，按理由，不是应该打印4次 people1，打印4次的people2吗？