如何使用Java RegEx匹配一组固定的字符
字符类使您可以接受一组固定字符中的单个字符。例如,
表达式“[tmp]”与字符t或m或p匹配。
表达式“[^tp]”与t或p之外的其他字符匹配。
例子1
import java.util.Scanner; import java.util.regex.Matcher; import java.util.regex.Pattern; public class Example { public static void main(String args[]) { //Reading String from user System.out.println("Enter a String"); Scanner sc = new Scanner(System.in); String input = sc.nextLine(); //Regular expression to match the characters t or, m or, p String regex = "[tmp]"; //Compiling the regular expression Pattern pattern = Pattern.compile(regex); //Retrieving the matcher object Matcher matcher = pattern.matcher(input); int count = 0; while(matcher.find()) { count++; } System.out.println("Occurrences: "+count); } }
输出结果
Enter a String hello how are you welcome to tutorialspoint Occurrences :6
例子2
import java.util.Scanner; import java.util.regex.Matcher; import java.util.regex.Pattern; public class Example { public static void main(String args[]) { //Reading String from user System.out.println("Enter a String"); Scanner sc = new Scanner(System.in); String input = sc.nextLine(); String regex = "[^abcdef]"; //Compiling the regular expression Pattern pattern = Pattern.compile(regex); //Retrieving the matcher object Matcher matcher = pattern.matcher(input); int count = 0; while(matcher.find()) { count++; } System.out.println("Occurrences :"+count); } }
输出结果
Enter a String Hello how are you welcome to tutorialspoint Occurrences :36