RxJava-筛选运算符 - 芒果文档

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📜 RxJava-筛选运算符

📅 最后修改于: 2020-11-12 05:28:48 🧑 作者: Mango

以下是用于从Observable中有选择地发射项目的运算符。

Sr.No.	Operator & Description
1	Debounce Emits items only when timeout occurs without emiting another item.
2	Distinct Emits only unique items.
3	ElementAt emit only item at n index emitted by an Observable.
4	Filter Emits only those items which pass the given predicate function.
5	First Emits the first item or first item which passed the given criteria.
6	IgnoreElements Do not emits any items from Observable but marks completion.
7	Last Emits the last element from Observable.
8	Sample Emits the most recent item with given time interval.
9	Skip Skips the first n items from an Observable.
10	SkipLast Skips the last n items from an Observable.
11	Take takes the first n items from an Observable.
12	TakeLast takes the last n items from an Observable.

过滤运算符示例

使用您选择的任何编辑器(例如，C：\> RxJava)创建以下Java程序。

ObservableTester.java

import io.reactivex.Observable;
//Using take operator to filter an Observable
public class ObservableTester  {
   public static void main(String[] args) {    
      String[] letters = {"a", "b", "c", "d", "e", "f", "g"};
      final StringBuilder result = new StringBuilder();
      Observable observable = Observable.fromArray(letters);
      observable
         .take(2)
         .subscribe( letter -> result.append(letter));
      System.out.println(result);
   }
}

验证结果

使用javac编译器编译类，如下所示：

C:\RxJava>javac ObservableTester.java

现在如下运行ObservableTester-

C:\RxJava>java ObservableTester

它应该产生以下输出-

ab