Java中的模式 asPredicate() 方法及示例

Pattern类的asPredicate()方法用于创建可用于匹配字符串的谓词对象。Predicate 是一个功能接口，因此可用作 lambda 表达式或方法引用的赋值目标。

句法：

public Predicate asPredicate()

参数：此方法不接受任何参数。

返回值：此方法返回一个可用于匹配字符串的谓词。

下面的程序说明了 toString() 方法：

方案一：

// Java program to demonstrate
// Pattern.splitAsStream(CharSequence input) method
  
import java.util.regex.*;
import java.util.function.*;
  
public class GFG {
    public static void main(String[] args)
    {
        // create a REGEX String
        String REGEX = "ee";
  
        // create the string
        // in which you want to search
        String actualString
            = "aaeebbeecceeddee";
  
        // create a Pattern using REGEX
        Pattern pattern
            = Pattern.compile(REGEX);
  
        // get Predicate Object
        Predicate predicate
            = pattern.asPredicate();
  
        // check whether predicate match
        // with actualString
        boolean value = predicate
                            .test(actualString);
  
        // print result
        System.out.println("value matched: "
                           + value);
    }
}

输出：

value matched: true

方案二：

// Java program to demonstrate
// Pattern.splitAsStream(CharSequence input) method
  
import java.util.regex.*;
import java.util.function.*;
public class GFG {
    public static void main(String[] args)
    {
        // create a REGEX String
        String REGEX = "org";
  
        // create the string
        // in which you want to search
        String actualString
            = "welcome geeks";
  
        // create a Pattern using REGEX
        Pattern pattern
            = Pattern.compile(REGEX);
  
        // get Predicate Object
        Predicate predicate
            = pattern.asPredicate();
  
        // check whether predicate match
        // with actualString
        boolean value
            = predicate.test(actualString);
  
        // print result
        System.out.println("value matched: "
                           + value);
    }
}

输出：

value matched: false

参考： https: Java/util/regex/Pattern.html#asPredicate()