【java】根据身份证，输出年月日

判断身份证：要么是15位，要么是18位，最后一位可以为字母，并写程序提出其中的年月日。

 15位和18位的身份证号码都是从7位到第12位为身份证为日期类型

package myDemo;import java.util.regex.Matcher;import java.util.regex.Pattern;public class IDRegex {public static void main(String[] args) {// 测试是否为合法的身份证号码String[] strs = { "130681198712092019", "13068119871209201x","13068119871209201", "123456789012345", "12345678901234x","1234567890123" };Pattern p1 = Pattern.compile("(\\d{17}[0-9a-zA-Z]|\\d{14}[0-9a-zA-Z])");  //正则表达式必须先编译为此类的实例for (int i = 0; i < strs.length; i++) {Matcher matcher = p1.matcher(strs[i]);  //创建匹配器System.out.println(strs[i] + ":" + matcher.matches());}Pattern p2 = Pattern.compile("\\d{6}(\\d{8}).*"); // 用于提取出生日字符串Pattern p3 = Pattern.compile("(\\d{4})(\\d{2})(\\d{2})");// 用于将生日字符串进行分解为年月日for (int i = 0; i < strs.length; i++) {Matcher matcher = p2.matcher(strs[i]);boolean b = matcher.find();if (b) {String s = matcher.group(1);Matcher matcher2 = p3.matcher(s);if (matcher2.find()) {System.out.println("生日为" + matcher2.group(1) + "年"+ matcher2.group(2) + "月"                              + matcher2.group(3) + "日");}}}}}