此类与所有可打印字符匹配。
import java.util.Scanner; import java.util.regex.Matcher; import java.util.regex.Pattern; public class PrintableCharacters { public static void main(String args[]) { //从用户读取字符串 System.out.println("Enter a string"); Scanner sc = new Scanner(System.in); String input = sc.nextLine(); //正则表达式 String regex = "[\\p{Print}]"; //Compiling the 正则表达式 Pattern pattern = Pattern.compile(regex); //检索匹配器对象 Matcher matcher = pattern.matcher(input); int count = 0; while(matcher.find()) { count++; } System.out.println("Number of printable characters: "+count); } }
Enter a string test Number of printable characters: 4
Enter a string öäüçãà Number of printable characters: 0
import java.util.Scanner; import java.util.regex.Matcher; import java.util.regex.Pattern; public class Example { public static void main( String args[] ) { //正则表达式 to match lower case letters String regex = "^\\p{Print}+$"; //获取输入数据 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 with only printable characters: "); 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: helloöäüçãà öäüçãà Hello1234 1234 welcome Strings with only printable characters: Hello1234 1234 welcome