”;
Following are the operators which are used to selectively emit item(s) from an Observable.
| 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. |
Filtering Operator Example
Create the following Java program using any editor of your choice in, say, C:> RxJava.
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<String> observable = Observable.fromArray(letters);
observable
.take(2)
.subscribe( letter -> result.append(letter));
System.out.println(result);
}
}
Verify the Result
Compile the class using javac compiler as follows −
C:RxJava>javac ObservableTester.java
Now run the ObservableTester as follows −
C:RxJava>java ObservableTester
It should produce the following output −
ab
”;