rxjava : flowable, observable

RxJava/ReactiveStream/src/main/java/_03_basic/FlowableEx.java

@@ -0,0 +1,53 @@
+package _03_basic;
+
+import io.reactivex.rxjava3.core.BackpressureStrategy;
+import io.reactivex.rxjava3.core.Flowable;
+import io.reactivex.rxjava3.schedulers.Schedulers;
+import org.reactivestreams.Subscriber;
+import org.reactivestreams.Subscription;
+
+public class FlowableEx {
+
+    public static void main(String[] args) {
+
+        Flowable<String> flowable = Flowable.create(emitter -> {
+            String[] data = {"Hello, World!", "Hello, RxJava!"};
+
+            for (String d : data) {
+                if (emitter.isCancelled()) {
+                    return;
+                }
+                emitter.onNext(d);
+            }
+            emitter.onComplete();
+        }, BackpressureStrategy.BUFFER);
+
+        flowable.observeOn(Schedulers.computation())
+                .subscribe(new Subscriber<String>() {
+
+                    private Subscription subscription;
+
+                    @Override
+                    public void onSubscribe(Subscription s) {
+                        this.subscription = s;
+                        this.subscription.request(1L); // 데이터 개수 요청
+                    }
+
+                    @Override
+                    public void onNext(String s) {
+                        System.out.println(s);
+                        this.subscription.request(1L); // 다음에 받을 데이터 개수 요청
+                    }
+
+                    @Override
+                    public void onError(Throwable t) {
+                        t.printStackTrace();
+                    }
+
+                    @Override
+                    public void onComplete() {
+                        System.out.println("complete");
+                    }
+                });
+    }
+}