java构造方法的简单问题

public class Student{
String name;
Float score;
public void setName(String _name) {
name=_name;
}
public String getName(){
return name;
}
public void setScore(Float _score) {
score=_score;
}
public float getScore(){
return score;
}
Student(){
stu1.setName();
stu1.setScore();
}
Student(String _name,Float _score) {
name=_name;
score=_score;
}
public void introduce(){
System.out.println("我的名字是"+name+",我的成绩为"+score+"!");
} 
}

public class Examp01{
public static void main(String[] args) {
Student stu1=new Student();
stu1.setName("Tom");
stu1.setScore("95.5");
stu1.introduce();
Student stu2=new Student("john",100.0);
stu2.introduce();
}

}