DoubleStream count() in Java with examples

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DoubleStream count() returns the count of elements in the stream. DoubleStream count() is present in java.util.stream.DoubleStream. This is a special case of a reduction i.e, it takes a sequence of input elements and combines them into a single summary result.
Syntax :

long count()

Note : This is a terminal operation i.e, it may traverse the stream to produce a result or a side-effect. After the terminal operation is performed, the stream pipeline is considered consumed, and can no longer be used.

Example 1 : Count the elements in DoubleStream.

// Java code for DoubleStream count()
// to count the number of elements in
// given stream
import java.util.*;
import java.util.stream.DoubleStream;
  
class GFG {
  
    // Driver code
    public static void main(String[] args)
    {
        // creating a DoubleStream
        DoubleStream stream = DoubleStream.of(2.3, 3.4, 4.5,
                                         5.6, 6.7, 7.8, 8.9);
  
        // storing the count of elements
        // in a variable named total
        long total = stream.count();
  
        // displaying the total number of elements
        System.out.println(total);
    }
}

Output:

Example 2 : Count distinct elements in DoubleStream.

// Java code for DoubleStream count()
// to count the number of distinct
// elements in given stream
import java.util.*;
import java.util.stream.DoubleStream;
  
class GFG {
  
    // Driver code
    public static void main(String[] args)
    {
        // creating a DoubleStream
        DoubleStream stream = DoubleStream.of(2.2, 3.3, 4.4,
                                        4.4, 7.6, 7.6, 8.0);
  
        // storing the count of distinct elements
        // in a variable named total
        long total = stream.distinct().count();
  
        // displaying the total number of elements
        System.out.println(total);
    }
}