正则表达式（二）

public static void main(String[] args) {
      String str1,str2,str3,pattern;    
      str1="fa";
      str2="f2";
      pattern="[a-z][0-9]";//匹配的格式两个字符，第一个字符范围是小写字母a-z，第二个范围是数字0-9
      Pattern r=Pattern.compile(pattern);
      Matcher m1=r.matcher(str1);
      Matcher m2=r.matcher(str2);
      System.out.println(m1.matches());//false
      System.out.println(m2.matches());//true
      //===============================================
      
      str1="中1";
      str2="1中";   
      //^代表字符串开头，$代表字符串结尾，\u4e00-\u9fa5是汉字
      pattern="^[\u4e00-\u9fa5][0-9]$";//匹配的格式两个字符,以汉字开头，数字结尾
      Pattern r1=Pattern.compile(pattern);
      Matcher m3=r1.matcher(str1);
      Matcher m4=r1.matcher(str2);
      System.out.println(m3.matches());//true
      System.out.println(m4.matches());//false
      
      //====================================================
      
      str1="1";
      str2="中";
      str3="1中";
      pattern="^[\u4e00-\u9fa50-9]$";//匹配的格式是一个字符，汉字或者数字
      Pattern r2=Pattern.compile(pattern);
      Matcher m5=r2.matcher(str1);
      Matcher m6=r2.matcher(str2);
      Matcher m7=r2.matcher(str3);
      System.out.println(m5.matches());//true
      System.out.println(m6.matches());//true
      System.out.println(m7.matches());//false
      
      //======================================
      
      str1="123456中8";
      str2="123456789";      
      //{8}代表匹配8次，长度=8，{8,}代表匹配8次以上，长度>=
      pattern="^[\u4e00-\u9fa50-9]{8}$";//
      Pattern r3=Pattern.compile(pattern);
      Matcher m8=r3.matcher(str1);
      Matcher m9=r3.matcher(str2);
      System.out.println(m8.matches());//true
      System.out.println(m9.matches());//false      
    }