大数据-java基础-第07章 字符串练习

1.输入内容，结尾以#键结束，并打印出内容

public class Exercise0102 { public static void main(String[] args) { // TODO Auto-generated method stub Scanner sc =new Scanner(System.in); int i =0; String couse1=" "; System.out.println("请输入内容 ："); while(i >=0){ String couse =sc.next(); char last =couse.charAt(couse.length()-1); if(last == '#') { break; } i++; couse1 = couse1+couse; } System.out.print("所有课程信息为："); System.out.print(couse1); } }

2.根据姓名和性别在控制台打印出，例如：姓名：李凯，性别：男。控制台输出：您好：李先生

public class Exercise0202 { public static void main(String[] args) { Scanner sn = new Scanner(System.in); System.out.println("请输入您的信息(格式为：姓 名,性别)："); String name = sn.nextLine(); name = name.replace(" ", "-"); int index1 =name.indexOf("-"); String name1; name1 = name.substring(0, index1); char sex = name.charAt(name.length()-1); if(sex =='男') { System.out.print("您好，"+name1+"先生"); }else { System.out.print("您好，"+name1+"女士"); } } }

3.设置一个小系统，登录邮箱和密码，邮箱进行判断，密码进行判断

public class Exercise04 { public static void main(String[] args) { System.out.print("***************用户登录系统************"); Scanner sc = new Scanner (System.in); System.out.print("\n请输入账号邮箱："); String email = sc.next(); if(email.indexOf("@")>0 &&email.indexOf("@")< email.indexOf(".")) { System.out.print("账号邮箱正确,请继续..."); }else { System.out.print("请输入账号邮箱有误！！,请重新输入"); } System.out.print("\n请输入第一次密码(区分大小写)："); String password1 = sc.next(); if (password1.length() < 8 || password1.length() > 16) { System.out.print("密码长度在8-16之间,请重新输入"); int i=0; while (i<3) { System.out.print("请在此输入第一次密码(区分大小写)："); password1 = sc.next(); i++; System.out.print("输入次数超过3次，请重新登录本系统"); } } else { System.out.print("请输入第二次密码(区分大小写)："); String password2 = sc.next(); if (password2.length() < 8 || password2.length() > 16) { System.out.print("密码长度在8-16之间,请重新输入"); } if(password1.equals(password2)) { System.out.print("密码正确"); }else { System.out.print("重新输入密码"); } } } }