📜  Java中的 LongStream noneMatch() 和示例

📅  最后修改于: 2022-05-13 01:54:48.447000             🧑  作者: Mango

Java中的 LongStream noneMatch() 和示例

LongStream noneMatch(LongPredicate predicate)返回此流的任何元素是否与提供的谓词匹配。如果不需要确定结果,它可能不会评估所有元素的谓词。这是一个短路端子操作。如果一个终端操作在有无限输入时可能会在有限时间内终止,那么它就是短路的。
句法 :

boolean noneMatch(LongPredicate predicate) 

参数 :

  1. LongPredicate :一个长值参数的谓词(布尔值函数)。

返回值:如果流的所有元素都与提供的谓词匹配或流为空,则该函数返回 true,否则返回 false。

注意:如果流为空,则返回 true 并且不评估谓词。

示例 1: noneMatch()函数检查 LongStream 的元素是否可被 5 整除。

// Java code for LongStream noneMatch
// (LongPredicate predicate) to check whether
// no element of this stream match
// the provided predicate.
import java.util.*;
import java.util.stream.LongStream;
  
class GFG {
  
    // Driver code
    public static void main(String[] args)
    {
        // Creating an LongStream
        LongStream stream = LongStream.of(3L, 5L, 9L, 12L, 14L);
  
        // Check if no element of stream
        // is divisible by 5 using
        // LongStream noneMatch(LongPredicate predicate)
        boolean answer = stream.noneMatch(num -> num % 5 == 0);
  
        // Displaying the result
        System.out.println(answer);
    }
}
输出:
false

例2: noneMatch()函数检查两个LongStream拼接后得到的LongStream中是否没有元素小于2。

// Java code for LongStream noneMatch
// (LongPredicate predicate) to check whether
// no element of this stream match
// the provided predicate.
import java.util.*;
import java.util.stream.LongStream;
  
class GFG {
  
    // Driver code
    public static void main(String[] args)
    {
        // Creating an LongStream after concatenating
        // two LongStreams
        LongStream stream = LongStream.concat(LongStream.of(3L, 4L, 5L, 6L),
                                              LongStream.of(7L, 8L, 9L, 10L));
  
        // Check if no element of stream
        // is less than 2 using
        // LongStream noneMatch(LongPredicate predicate)
        boolean answer = stream.noneMatch(num -> num < 2);
  
        // Displaying the result
        System.out.println(answer);
    }
}
输出:
true

示例 3: noneMatch()函数显示流是否为空,则返回 true。

// Java code for LongStream noneMatch
// (LongPredicate predicate) to check whether
// no element of this stream match
// the provided predicate.
import java.util.*;
import java.util.stream.LongStream;
  
class GFG {
  
    // Driver code
    public static void main(String[] args)
    {
        // Creating an empty LongStream
        LongStream stream = LongStream.empty();
  
        // Using LongStream noneMatch() on empty stream
        boolean answer = stream.noneMatch(num -> true);
  
        // Displaying the result
        System.out.println(answer);
    }
}
输出:
true