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  • 吴裕雄--天生自然java开发常用类库学习笔记:一对多关系范例

    import java.util.List ;
    import java.util.ArrayList ;
    public class School{
        private String name ;
        private List<Student> allStudents ;
        public School(){
            this.allStudents = new ArrayList<Student>() ;
        }
        public School(String name){
            this() ;
            this.setName(name) ;
        }
        public void setName(String name){
            this.name = name ;
        }
        public String getName(){
            return this.name; 
        }
        public List<Student> getAllStudents(){
            return this.allStudents ;
        }
        public String toString(){
            return "学校名称:" + this.name ;
        }
    };
    public class Student{
        private String name ;
        private int age ;
        private School school; // 一个学生属于一个学校
        public Student(String name,int age){
            this.setName(name) ;
            this.setAge(age) ;
        }
        public void setSchool(School school){
            this.school = school ;
        }
        public School getSchool(){
            return this.school ;
        }
        public void setName(String name){
            this.name = name ;
        }
        public void setAge(int age){
            this.age = age ;
        }
        public String getName(){
            return this.name; 
        }
        public int getAge(){
            return this.age ;
        }
        public String toString(){
            return "学生姓名:" + this.name + ";年龄:" + this.age ;
        }
    };
    import java.util.Iterator ;
    public class TestDemo{
        public static void main(String args[]){
            School sch = new School("清华大学") ;    // 定义学校
            Student s1 = new Student("张三",21) ;
            Student s2 = new Student("李四",22) ;
            Student s3 = new Student("王五",23) ;
            sch.getAllStudents().add(s1) ;
            sch.getAllStudents().add(s2) ;
            sch.getAllStudents().add(s3) ;
            s1.setSchool(sch) ;
            s2.setSchool(sch) ;
            s3.setSchool(sch) ;
            System.out.println(sch) ;
            Iterator<Student> iter = sch.getAllStudents().iterator() ;
            while(iter.hasNext()){
                System.out.println("	|- " + iter.next()) ;
            }
        }
    };
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  • 原文地址:https://www.cnblogs.com/tszr/p/12152787.html
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