LongStream mapToObj() in Java

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LongStream mapToObj() returns an object-valued Stream consisting of the results of applying the given function.

Note : LongStream mapToObj() is a intermediate operation. These operations are always lazy. Intermediate operations are invoked on a Stream instance and after they finish their processing, they give a Stream instance as output.
Syntax :

<U> Stream<U> mapToObj(LongFunction<? extends U> mapper)

Parameters :

U : The element type of the new stream.
Stream : A sequence of elements supporting sequential and parallel aggregate operations.
LongFunction : Represents a function that accepts a long-valued argument and produces a result.
mapper : A stateless function to apply to each element.

Return Value : The function returns an object-valued Stream consisting of the results of applying the given function.

Example 1 :

// Java code for LongStream mapToObj
// (LongFunction mapper)
import java.util.*;
import java.util.stream.Stream;
import java.util.stream.LongStream;
  
class GFG {
  
    // Driver code
    public static void main(String[] args)
    {
        // Creating an LongStream
        LongStream stream = LongStream.range(3L, 8L);
  
        // Creating a Stream of Strings
        // Using LongStream mapToObj(LongFunction mapper)
        // to store binary representation of
        // elements in LongStream
        Stream<String> stream1 = stream.mapToObj(num
                                                 -> Long.toBinaryString(num));
  
        // Displaying an object-valued Stream
        // consisting of the results of
        // applying the given function.
        stream1.forEach(System.out::println);
    }
}

Output :

Example 2 :

// Java code for LongStream mapToObj
// (LongFunction mapper)
import java.util.*;
  
import java.math.BigInteger;
import java.util.stream.Stream;
import java.util.stream.LongStream;
  
class GFG {
  
    // Driver code
    public static void main(String[] args)
    {
        // Creating an LongStream
        LongStream stream = LongStream.of(3L, 5L, 7L, 9L, 11L);
  
        // Creating a Stream
        // Using LongStream mapToObj(LongFunction mapper)
        Stream<BigInteger> stream1 = stream
                                         .mapToObj(BigInteger::valueOf);
  
        // Displaying an object-valued Stream
        // consisting of the results of
        // applying the given function.
        stream1.forEach(num -> System.out.println(num.add(BigInteger.TEN)));
    }
}