Java DoubleStream filter()示例

DoubleStream filter(DoublePredicate predicate) 返回一个由这个流中符合给定谓词的元素组成的流。这是一个 中间操作。 这些操作总是懒惰的，即执行中间操作如filter()实际上并不执行任何过滤，而是创建一个新的流，当遍历时，包含初始流中符合给定谓词的元素。

语法:

DoubleStream filter(DoublePredicate predicate)

参数

DoubleStream : 一个原始双值元素的序列。DoublePredicate : 一个双值参数的谓词（布尔值函数）。

返回值： 该函数返回新的流。

例1： DoubleStream的filter()方法。

// Java code for DoubleStream filter// (DoublePredicate predicate) to get a stream// consisting of the elements of this// stream that match the given predicate.import java.util.*;import java.util.stream.DoubleStream;  class GFG {      // Driver code    public static void main(String[] args)    {        // Creating an DoubleStream        DoubleStream stream = DoubleStream.of(3.6, 5.4, 6.6, 8.1, 9.7);          // Using DoubleStream filter(DoublePredicate predicate)        // to get a stream consisting of the        // elements that are greater than 5.7        stream.filter(num -> num > 5.7)            .forEach(System.out::println);    }}

输出:

6.68.19.7

例2： DoubleStream的filter()方法。

// Java code for DoubleStream filter// (DoublePredicate predicate) to get a stream// consisting of the elements of this// stream that match the given predicate.import java.util.*;import java.util.stream.DoubleStream;  class GFG {      // Driver code    public static void main(String[] args)    {        // Creating an DoubleStream        DoubleStream stream = DoubleStream.of(3.6, 5.4, 6.6, 8.1, 9.7);          // Using DoubleStream filter(DoublePredicate         // predicate) to get a stream consisting of         // the elements that when divided by 2        // gives quotient > 2.3        stream.filter(num -> num / 2.0 > 2.3)            .forEach(System.out::println);    }}

输出:

5.46.68.19.7