following are the operators which are used to create a single observable from multiple observables.
| sr.no. | operator & description |
|---|---|
| 1 |
and/then/when
combine item sets using pattern and plan intermediaries. |
| 2 |
combinelatest
combine the latest item emitted by each observable via a specified function and emit resulted item. |
| 3 |
join
combine items emitted by two observables if emitted during time-frame of second observable emitted item. |
| 4 |
merge
combines the items emitted of observables. |
| 5 |
startwith
emit a specified sequence of items before starting to emit the items from the source observable |
| 6 |
switch
emits the most recent items emitted by observables. |
| 7 |
zip
combines items of observables based on function and emits the resulted items. |
combining operator example
create the following java program using any editor of your choice in, say, c:\> rxjava.
observabletester.java
import io.reactivex.observable;
//using combinelatest operator to combine observables
public class observabletester {
public static void main(string[] args) {
integer[] numbers = { 1, 2, 3, 4, 5, 6};
string[] letters = {"a", "b", "c", "d", "e", "f", "g"};
final stringbuilder result = new stringbuilder();
observable<string> observable1 = observable.fromarray(letters);
observable<integer> observable2 = observable.fromarray(numbers);
observable.combinelatest(observable1, observable2, (a,b) -> a + b)
.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 −
g1g2g3g4g5g6