Java : String作业

import java.util.Arrays;
public class Diyi {
  public static void main(String[] args) {
    xiazhi121();
  }
  public static void xiazhi121() {
    char[] nums = { 'A', 'B', 'C' };
    char[] array= nums;
    String sum = Arrays.toString(array);//转换成String类型
    System.out.println(sum);
  }
}

import java.util.Scanner;
public class Dier {
  public static void main(String[] args) {
        xiazhi121();
  }
  public static void xiazhi121() {
    Scanner sc = new Scanner(System.in);
    System.out.println("请输入需要反转的字符串：");
        String line = sc.nextLine();
    StringBuffer fanzhuang = new StringBuffer(line);
        fanzhuang = fanzhuang.reverse();//字符串反序输出
        System.out.println("反转之后的字符串为：" +"\n" + fanzhuang);
  }
}

public class Disan {
  public static void main(String[] args) {
    xiazhi121();
  }
    public static void xiazhi121(){
      String s = "ddffffbbbdddbbbfdsa";
      System.out.println("第一个字符串为："+s);
      String s2="bbb";
      System.out.println("第二个字符串为："+s2);
        String s1 = s.replace("bbb", "");
        int count = (s.length() -s1.length())/s2.length();//统计次数
        System.out.println("第二个字符串在第一个字符串出现的次数："+count+"次");
    }
}

public class Dishi {
  public static void main(String args[]) {
    deldteCharAt();
  }
  public static void deldteCharAt() {
    String str = "abcdDaCBA123";
    System.out.println("删除前的字符串为：" + str);
    String strNew = str.replace("a", "");//删除字符
    System.out.println("删除a字符之后：" + strNew);
  }
}

import java.util.Scanner;
public class Diwu {
  public static void main(String[] args) {
    xiazhi121();
  }
  public static void xiazhi121() {
    Scanner sc = new Scanner(System.in);
    System.out.println("请输入一个网站名：");
    String line = sc.nextLine();
    String[] firstArray = line.split("\\.");//按照“.”分割
    for (String a : firstArray) {
      System.out.print(a + "    ");//按要求输出
    }
  }
}

public class Diliu {
  public static void main(String[] args) {
    xiazhi121();
  }
  public static void xiazhi121() {
    String str = "      abc    ";
    System.out.println("去除空格前：" + str);
    String quchu = str.trim();//忽略字符串首尾处空白
    System.out.println("去除空格后：" + quchu);
  }
}

import java.util.Scanner;
public class Diqi {
  public static void main(String[] args) {
    xiazhi121();
  }
  public static void xiazhi121() {
    Scanner sc = new Scanner(System.in);
    System.out.println("请输入一个身份证号：");
    String s = sc.nextLine();
    int i = 18;
    if (i != s.length()) {
      System.out.println("输入身份证号码有误");//多活动少提示输入错误
    } else {
      String year = s.substring(6, 10);//取身份证的年份
      String month = s.substring(10, 12);//取身份证的月份
      String day = s.substring(12, 14);//取身份证的天
      System.out.println("出生年月日为：" + year + "年" + month + "月" + day + "日");
      String sex = s.substring(16, 17);//取身份证代表性别的位数
      int a = Integer.valueOf(sex);
      if (a % 2 == 0) {
        System.out.println("此身份证号码的人是女性");
      } else {
        System.out.println("此身份证号码的人是男性");
      }
      String[] sun = { "11", "12", "13", "14", "15", "21", "22", "23", "31", "32", "33", "34", "35", "36", "37",
          "41", "42", "43", "44", "45", "46", "50", "51", "52", "53", "54", "61", "62", "63", "64", "65",
          "71", "81", "82" };//身份证对应的身份证第一位和第二位
      String[] sum = { "北京市", "天津市", "河北省", "山西省", "内蒙古自治区", "辽宁省", "吉林省", "黑龙江省", "上海市", " 江苏省", "浙江省", "安徽省",
          "福建省", "江西省", "山东省", " 河南省", "湖北省", " 湖南省", "广东省", " 广西壮族自治区", "海南省", "重庆市", "四川省", "贵州省", "云南省",
          " 西藏自治区", "陕西省", "甘肃省", "青海省", "宁夏回族自治区", "新疆维吾尔自治区", "台湾省", "香港特别行政区", "澳门特别行政区" };
      String pos = (s.substring(0, 2));//取出身份证一二位
      int sheng;
      for ( sheng = 0; sheng < sun.length; sheng++) {
        if (pos.equals(sun[sheng])) {
          break;//找到对应的省份退出循环
        }
      }
      System.out.println("此身份证的省份为：" + sum[sheng]);
    }
  }
}