Java Teacher 类实例化错误及解决方法

在 Java 中，类名是大小写敏感的。当我们试图使用小写 'teacher' 实例化 Teacher 类时，会遇到编译错误。

错误代码示例：

class Teacher{
    String name,college,department;
    int age;
     public void teacher(){
         name = '老师';
         age = 0;
         college = '大学';
         department = '系部';
    }

    public void assignmentNA(String username, int userage){
         this.name = username;
         this.age = userage;
    }
    void assignmentNACD(String username, int userage, String usercollege, String userdepartment){
        this.name = username;
        this.age = userage;
        this.age = userage;
        this.college = usercollege;
        this.department = userdepartment;
    }
    public void printInfo(){
        System.out.println('name'+ name);
        System.out.println('age'+ age);
        System.out.println('college'+ college);
        System.out.println('department'+ department);
    }
}


public class TeacherTest{
    public static void main(String[] args) {
        Teacher t1 = new teacher(); // 这里错误
    }
}

错误原因：

在 TeacherTest 类中，创建 Teacher 对象时应该使用 Teacher 类而不是 teacher 类（注意大小写）。

正确代码：

class Teacher{
    String name,college,department;
    int age;
     public void teacher(){
         name = '老师';
         age = 0;
         college = '大学';
         department = '系部';
    }

    public void assignmentNA(String username, int userage){
         this.name = username;
         this.age = userage;
    }
    void assignmentNACD(String username, int userage, String usercollege, String userdepartment){
        this.name = username;
        this.age = userage;
        this.age = userage;
        this.college = usercollege;
        this.department = userdepartment;
    }
    public void printInfo(){
        System.out.println('name'+ name);
        System.out.println('age'+ age);
        System.out.println('college'+ college);
        System.out.println('department'+ department);
    }
}


public class TeacherTest{
    public static void main(String[] args) {
        Teacher t1 = new Teacher(); // 修改后的代码
    }
}

总结：

在 Java 中，类名是大小写敏感的。创建对象时，必须使用正确的类名，并且确保大小写一致。