子表达式“ [...] ”匹配括号中指定的任何单个字符。
import java.util.regex.Matcher; import java.util.regex.Pattern; public class SpecifiedCharacters { public static void main( String args[] ) { String regex = "[hwt]"; String input = "Hi how are you welcome to Nhooo"; Pattern p = Pattern.compile(regex); Matcher m = p.matcher(input); int count = 0; while(m.find()) { count++; } System.out.println("Number of matches: "+count); } }
输出结果
Number of matches: 6
以下Java程序从用户那里接收5个字符串,并打印包含元音字母的字符串/单词。
import java.util.Scanner; import java.util.regex.Matcher; import java.util.regex.Pattern; public class RegexExample { public static void main( String args[] ) { String regex = "^.*[aeiou].*$"; Scanner sc = new Scanner(System.in); System.out.println("Enter 5 input strings: "); String input[] = new String[5]; for (int i=0; i<5; i++) { input[i] = sc.nextLine(); } //创建一个Pattern对象 Pattern p = Pattern.compile(regex); System.out.println("strings that contain vowel letters: "); for(int i=0; i<5;i++) { //创建一个Matcher对象 Matcher m = p.matcher(input[i]); if(m.matches()) { System.out.println(m.group()); } } } }
输出结果
Enter 5 input strings: hello sample rhythm cry gym strings that contain vowel letters: hello sample