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);
}
}