请教，为何输入“数据结构”后，打印出来的是乱码？谢谢

package com.imooc.collection;

import java.util.ArrayList;
import java.util.Arrays;
import java.util.HashSet;
import java.util.List;
import java.util.Scanner;
import java.util.Set;

public class SetTest {
	public List<Course> coursesToSelect;
	private Scanner console;
	public Student student;
	public SetTest(){
		this.coursesToSelect=new ArrayList<Course>();
	}

public void testAdd(){
		Course cr1=new Course("1","数据结构");
		coursesToSelect.add(cr1);
		
		Course cr2=new Course("2","C");
		coursesToSelect.add(0, cr2);
		
		Course[] course={new Course("3","汇编语言"),new Course("4","计算机原理")};
		coursesToSelect.addAll(Arrays.asList(course));
		
		Course[] course2={new Course("5","离散数学"),new Course("6","大学英语")};
		coursesToSelect.addAll(4, Arrays.asList(course2));

	}

public void testForEach(){
	System.out.println("待选课程如下：(通过foreach来选择)");
	for(Course cr:coursesToSelect){
		//Course cr=(Course)obj;
		System.out.println(cr.id+" "+cr.name);
	}
}

	public void testListContains(){
		Course course=coursesToSelect.get(0);
		System.out.println("取得课程："+course.name);
		System.out.println("备选课程中是否包含课程："+course.name+","+coursesToSelect.contains(course));
		Course course2=new Course(course.id,course.name);
		System.out.println("新创建课程："+course2.name);
		System.out.println("备选课程中是否包含课程："+course2.name+","+coursesToSelect.contains(course2));
	}

	public void createStudentAndSelectCourse(){
		student=new Student("1","小莫");
		System.out.println("欢迎学生："+student.name+"选课！");
		console=new Scanner(System.in);
		
		for(int i=0;i<3;i++){
			System.out.println("请输入课程ID");
			String courseId=console.next();
			for(Course cr:coursesToSelect){
				if(cr.id.equals(courseId)){
					student.courses.add(cr);
				}
			}
		}
	}
	public void testSetContains(){
		System.out.println("请输入学生已选的课程名称：");
		console=new Scanner(System.in);
		String name=console.next();
		Course course2=new Course();
		course2.name=name;
		System.out.println("新创建课程："+course2.name);
		System.out.println("已选课程中是否包含课程："+course2.name+","+student.courses.contains(course2));
	}
	
	public static void main(String[] args) {
		// TODO Auto-generated method stub
		SetTest st=new SetTest();
		st.testAdd();
		st.testForEach();
		st.createStudentAndSelectCourse();
		st.testForEachForSet(st.student);
		st.testSetContains();
	}
	
	public void testForEachForSet(Student student){
		System.out.println("共选择了："+student.courses.size());
		for(Course cr:student.courses){
			System.out.println("选择了课程："+cr.name);
		}
	}

}