I have this 2 questions. These are few of my classes. Where is my problem? I can`t automaticly make constructor, only manually and in the 1st class, I getting wrong results when loop over arraylist(sorry for my bad english)

**Test Class:**

```
    package schoolPackage;

    public class MainClass {

    public static void main(String[] args) {

        Students student1 = new Students("pe6o", 28);
        Students student2 = new Students("Iv", 15);
        Students student3 = new Students("Ivan ", 2);
        Students student4 = new Students("Ivan M", 155);
        Students student5 = new Students("Ivan Mil", 222);
        Students student6 = new Students("go6o", 12);
        Students student7 = new Students("sa6o", 1224);

        School.addStudent(student1);
        School.addStudent(student2);
        School.addStudent(student3);
        School.addStudent(student4);
        School.addStudent(student5);
        School.addStudent(student6);
        School.addStudent(student7);
        School.allStudentsInfo();

    }

}

```

**School.java:**

```
 package schoolPackage;

    import java.util.ArrayList;
    import java.util.Iterator;

    public class School {

        private static ArrayList<SchoolClass> clasess = new ArrayList<SchoolClass>();
        private static ArrayList<Students> students = new ArrayList<Students>();

        static void addClass(SchoolClass schoolClass) {

            clasess.add(schoolClass);

        }

        static void addStudent(Students student) {
            students.add(student);

        }

        public static void removeStudents(String name) {
            Iterator<Students> studentss = students.iterator();

            while (studentss.hasNext()) {
                Students str = studentss.next();

                if (str.getName().equalsIgnoreCase(name)) {
                    studentss.remove();
                }
            }

        }

        public static void removeSchoolClasses(String ID) {
            Iterator<SchoolClass> SClasses = clasess.iterator();

            while (SClasses.hasNext()) {
                SchoolClass str = SClasses.next();

                if (str.getClassID().equalsIgnoreCase(ID))
                    ;
                SClasses.remove();
            }

        }

        public static void allStudentsInfo() {
            for (Students stud : students) {
                System.out.println(Students.getNumberInClass());
            }
        }

    }

```

**SchoolClass.java**

```
package schoolPackage;

import java.util.ArrayList;

public class SchoolClass {

    private String classID;

    public String getClassID() {
        return classID;
    }

    public void setClassID(String classID) {
        this.classID = classID;
    }

    public SchoolClass(String classID) {
        super();
        this.classID = classID;
    }

    private static ArrayList<Teacher> teachers = new ArrayList<Teacher>();

    private static void addTeacher(Teacher teacher) {

        teachers.add(teacher);

    }

}

```