IntStream of(int t)
IntStream of(int t) returns a sequential IntStream containing a single element.
Syntax :
static IntStream of(int t)
Parameters :
- IntStream : A sequence of primitive int-valued elements.
- t : Represents the single element in the IntStream.
Return Value : IntStream of(int t) returns a sequential IntStream containing the single specified element.
Example :
Java
// Java code for IntStream of(int t)// to get a sequential IntStream// containing a single element.import java.util.*;import java.util.stream.IntStream;class GFG { // Driver code public static void main(String[] args) { // Creating an IntStream having single element only IntStream stream = IntStream.of(-7); // Displaying the IntStream having single element stream.forEach(System.out::println); }} |
Output :
-7
IntStream of(int… values)
IntStream of(int… values) returns a sequential ordered stream whose elements are the specified values.
Syntax :
static IntStream of(int... values)
Parameters :
- IntStream : A sequence of primitive int-valued elements.
- values : Represents the elements of the new stream.
Return Value : IntStream of(int… values) returns a sequential ordered stream whose elements are the specified values.
Example 1 :
Java
// Java code for IntStream of(int... values)// to get a sequential ordered stream whose// elements are the specified values.import java.util.*;import java.util.stream.IntStream;class GFG { // Driver code public static void main(String[] args) { // Creating an IntStream IntStream stream = IntStream.of(-7, -9, -11); // Displaying the sequential ordered stream stream.forEach(System.out::println); }} |
Output :
-7 -9 -11
Example 2 :
Java
// Java code for IntStream of(int... values)// to get a sequential ordered stream whose// elements are the specified values.import java.util.*;import java.util.stream.IntStream;class GFG { // Driver code public static void main(String[] args) { // Creating an IntStream IntStream stream = IntStream.of(-7, -9, -11); // Storing the count of elements in IntStream long total = stream.count(); // Displaying the count of elements System.out.println(total); }} |
Output :
3
Example 3
Streams are not reusable if we have performed terminal operation on stream and try to reuse them again IllegalStateExeception will be generated
Java
import java.util.stream.IntStream;import java.io.PrintStream;class GFG{ static final PrintStream out=System.out; public static void main(String $[]){ IntStream intStream=IntStream.of(10,20,30); out.println(intStream.min()); try{ out.println(intStream.min());//Trying to use a stream that has been closed previously }catch(IllegalStateException e){ out.println(e); } }} |
Output :
OptionalInt[10] java.lang.IllegalStateException: stream has already been operated upon or closed
To reuse a stream we need Supplier class when get() method of Supplier is called every time it will generate a new instance and return it.
Java
import java.util.stream.IntStream;import java.io.PrintStream;import java.util.function.Supplier;import java.util.List;import java.util.stream.Collectors;public class IntStreamClass{ static final PrintStream out=System.out; public static void main(String $[]){ //Reusing a stream Supplier<IntStream>supplier=()->IntStream.of(343,434,61,1,512, 5234,613434,561); //supplier.get() will return an instance of IntStream //sorting -> printing each value supplier.get() .sorted() .forEach(System.out::println); out.println(); //filtering even numbers -> sorting -> printing each value supplier.get() .filter(x->x%2==0) .sorted() .forEach(System.out::println); out.println(); //filtering odd numbers -> boxing(converting to Integer) -> converted to List<Integer> -> streaming -> sorting in reverse order //-> printing each value supplier.get() .filter(x->(x&1)==0) .boxed() .collect(Collectors.toList()) .stream() .sorted((a,b)->b-a) .forEach(System.out::println); }} |
Output :
1 61 343 434 512 561 5234 613434 434 512 5234 613434 613434 5234 512 434
Example 4
Finding min,max,sum and average from an IntStream
Java
import java.util.stream.IntStream;import java.io.PrintStream;import java.util.function.Supplier;import java.util.OptionalInt;import java.util.OptionalDouble;public class IntStreamClass{ static final PrintStream out=System.out; public static void main(String $[]){ Supplier<IntStream>supplier=()->IntStream.of(343,434,61,1,512, 5234,613434,561); //Average OptionalDouble avg=supplier.get().average(); out.println("Average : "+avg.orElse(0)); // Sum int sum=supplier.get().sum(); out.println("Sum : "+sum); // Min OptionalInt min=supplier.get().min(); out.println("min : "+min.orElse(0)); // Max OptionalInt max=supplier.get().max(); out.println("max : "+max.orElse(0)); }} |
Output :
Average : 77572.5 Sum : 620580 min : 1 max : 613434
Example 5
Range based operation
Java
import java.util.stream.IntStream;import java.io.PrintStream;import java.util.function.Supplier;import java.util.OptionalInt;import java.util.OptionalDouble;public class IntStreamClass{ static final PrintStream out=System.out; public static void main(String $[]){ //Range //Will iterate from 0 to 5 IntStream.range(0,6) .forEach(System.out::println); out.println(); //Will iterate from 0 to 6 IntStream.rangeClosed(0,6) .forEach(System.out::println); out.println(); //rangeSum=0+1+2+3+...+99=4950 int rangeSum=IntStream.range(0,100).sum(); out.println("sum[0,100) : "+rangeSum); //rangeClosedSum=0+1+2+3+...+100=5050 int rangeClosedSum=IntStream.rangeClosed(0,100).sum(); out.println("sum[0,100] : "+rangeClosedSum); }} |
