实验3 字符串应用与面向对象程序设计 编写一个Java项目，模拟一次包括老师备课，同学上课，布置作业和做作业的课堂教学过程。作业为判断字符串是否为2-重复串及其他字符串操作内容。-Experiment 3 string applications and object-oriented programming to write a Java program to simulate the time, including teacher preparation, the students in