import java.util.regex.Matcher; import java.util.regex.Pattern; public class RegexDemo { public static void main(String[] args) { // 1. compile(String regex) 将给定的正则表达式编译到模式中。 // 2. matcher(CharSequence input) 创建匹配给定输入与此模式的匹配器。 // 3. matches() 尝试将整个区域与模式匹配。 String str = "abc"; // 1.编译正则规则形式 Pattern p = Pattern.compile("abc"); // 2.将正则进行匹配 Matcher m = p.matcher(str); // 3.进行判断 boolean b = m.matches(); System.out.println(b); String str2 = "agx"; Pattern p2 = Pattern.compile("[abc][efgh][xyz]"); Matcher m2 = p2.matcher(str2); boolean b2 = m2.matches(); System.out.println(b2); String str3 = "agx"; System.out.println(str3.matches("[abc][efgh][xyz]")); String str4 = "D"; Pattern p4 = Pattern.compile("[a-zA-Z]"); Matcher m4 = p4.matcher(str4); boolean b4 = m4.matches(); System.out.println(b4); String str5 = "5"; System.out.println(str5.matches("[0-9]")); String str6 = "Hello world, this is java code."; String pattern6 = ".*world.*"; boolean b6 = Pattern.matches(pattern6, str6); System.out.println(b6); String str7 = "I have a dream."; String pattern7 = ".*dream"; boolean b7 = Pattern.matches(pattern7, str7); System.out.println(b7); } }