請教，為何輸入“數(shù)據(jù)結構”后，打印出來的是亂碼？謝謝

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","數(shù)據(jù)結構");
		coursesToSelect.add(cr1);
		
		Course?cr2=new?Course("2","C");
		coursesToSelect.add(0,?cr2);
		
		Course[]?course={new?Course("3","匯編語言"),new?Course("4","計算機原理")};
		coursesToSelect.addAll(Arrays.asList(course));
		
		Course[]?course2={new?Course("5","離散數(shù)學"),new?Course("6","大學英語")};
		coursesToSelect.addAll(4,?Arrays.asList(course2));

	}

public?void?testForEach(){
	System.out.println("待選課程如下：(通過foreach來選擇)");
	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("取得課程："+course.name);
		System.out.println("備選課程中是否包含課程："+course.name+","+coursesToSelect.contains(course));
		Course?course2=new?Course(course.id,course.name);
		System.out.println("新創(chuàng)建課程："+course2.name);
		System.out.println("備選課程中是否包含課程："+course2.name+","+coursesToSelect.contains(course2));
	}

	public?void?createStudentAndSelectCourse(){
		student=new?Student("1","小莫");
		System.out.println("歡迎學生："+student.name+"選課！");
		console=new?Scanner(System.in);
		
		for(int?i=0;i<3;i++){
			System.out.println("請輸入課程ID");
			String?courseId=console.next();
			for(Course?cr:coursesToSelect){
				if(cr.id.equals(courseId)){
					student.courses.add(cr);
				}
			}
		}
	}
	public?void?testSetContains(){
		System.out.println("請輸入學生已選的課程名稱：");
		console=new?Scanner(System.in);
		String?name=console.next();
		Course?course2=new?Course();
		course2.name=name;
		System.out.println("新創(chuàng)建課程："+course2.name);
		System.out.println("已選課程中是否包含課程："+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("共選擇了："+student.courses.size());
		for(Course?cr:student.courses){
			System.out.println("選擇了課程："+cr.name);
		}
	}

}