1、事前に定義された文字クラス
-
任意の文字
-
\ D数字：[0-9]
-
\ D非数値：[^ 0-9]
-
\ S空白：[\ T \ n \ X0B \ F \ R]
-
\は非空白文字がS：[^ \ sを]
-
\ W単語文字：[-ZA-Z_0-9]
-
\ W非単語の文字：[^ \ W]
図2に示すように、コード
public class Demo3_Regex {
/**
* . 任何字符
\d 数字：[0-9]
\D 非数字： [^0-9]
\s 空白字符：[ \t\n\x0B\f\r]
\S 非空白字符：[^\s]
\w 单词字符：[a-zA-Z_0-9]
\W 非单词字符：[^\w]
*/
public static void main(String[] args) {
//demo1();
//demo2();
//demo3();
//demo4();
//demo5();
//demo6();
String regex = "\\W";
System.out.println("a".matches(regex));
System.out.println("z".matches(regex));
System.out.println("_".matches(regex));
System.out.println("%".matches(regex));
}
private static void demo6() {
String regex = "\\w";
System.out.println("a".matches(regex));
System.out.println("z".matches(regex));
System.out.println("_".matches(regex));
System.out.println("%".matches(regex));
}
private static void demo5() {
String regex = "\\S";
System.out.println(" ".matches(regex));
System.out.println(" ".matches(regex));
System.out.println("a".matches(regex));
}
private static void demo4() {
String regex = "\\s";
System.out.println(" ".matches(regex));
System.out.println(" ".matches(regex)); //一个tab键
System.out.println(" ".matches(regex)); //四个空格
}
private static void demo3() {
String regex = "\\D";
System.out.println("0".matches(regex));
System.out.println("9".matches(regex));
System.out.println("a".matches(regex));
}
private static void demo2() {
String regex = "\\d"; //\代表转义字符,如果想表示\d的话,需要\\d
System.out.println("0".matches(regex));
System.out.println("a".matches(regex));
System.out.println("9".matches(regex));
}
private static void demo1() {
String regex = "..";
System.out.println("a".matches(regex));
System.out.println("ab".matches(regex));
}
}
3.結果
