RxJava 常用Subject特性总结(参考)

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AsyncSubject

  • 无论订阅时机(包括在调用onComplete后订阅),在调用onComplete后都可以接收到onComplete之前输入的最后一个值
  • 没调用onComplete,不输出


BehaviorSubject

  • 会在订阅后(在调用onComplete后订阅无效),可以接收到发送离订阅最近的上一个值以及调用onComplete之前的值
  • 接收的范围:订阅时的前一个值+订阅后---调用onComplete之前所发送的值 (subject.onNext())
  • 没有上一个值的时候会发送默认值。没有默认值不发送。
 BehaviorSubject<String> subject = BehaviorSubject.createDefault("0");//添加默认值


PublishSubject

  • 和BehaviorSubject类似,只是接收不到发送离订阅最近的上一个值。
  • 接收的范围:订阅后---调用onComplete之前所发送的值 (subject.onNext())

ReplaySubject

  • 最简单的,无论订阅时机(包括在调用onComplete后订阅),也无论是否调用onComplete(),或是在数据发送前订阅,都会将所有发送过的内容全部发给订阅者


示例代码

 public static void rxJava() {
        //替换 ReplaySubject,BehaviorSubject,AsyncSubject
        PublishSubject loadPersonsCommand;

        PublishSubject<String> subject = PublishSubject.create();
        Disposable disposable0 = subject.subscribe(new Consumer<String>() {
            @Override
            public void accept(String s) throws Exception {
                LogUtils.e("disposable0==" + s);
            }
        });
        subject.onNext("1");
        subject.onNext("2");
        Disposable disposable1 = subject.subscribe(new Consumer<String>() {
            @Override
            public void accept(String s) throws Exception {
                LogUtils.e("disposable1==" + s);
            }
        });
        subject.onNext("3");
        subject.onNext("4");
        subject.onNext("5");
        Disposable disposable2 = subject.subscribe(new Consumer<String>() {
            @Override
            public void accept(String s) throws Exception {
                LogUtils.e("disposable2==" + s);

            }
        });
        subject.onNext("6");
        subject.onNext("7");
        subject.onNext("8");
        subject.onComplete();
        subject.subscribe(new Observer<String>() {
            @Override
            public void onSubscribe(Disposable d) {

            }

            @Override
            public void onNext(String s) {
                LogUtils.e("disposable3==" + s);
            }

            @Override
            public void onError(Throwable e) {
                LogUtils.e("disposable3==" + e.getMessage());
            }

            @Override
            public void onComplete() {

            }
        });
        subject.onNext("9");
        subject.onNext("10");
    }