Data table and simple Java conversion _A practical case of reference relationship

To carry out relationship design, the data table corresponds to the following relationships: 1. An employee belongs to a department and needs to add a department reference; 2. An employee has a leader, and the leader must be related to himself and cited by himself 3. A department has multiple employees

//部门类class Dept{    private int deptno;//部门编号
    private String dname;//部门名称
    private String loc;//部门位置

    private Emp emps[];//“引用关系” 多个雇员,描述多这个概念应该使用对象数组进行完成

    //明确定义一个无参构造
    public Dept(){      
    }    public Dept(int deptno,String dname,String loc){//有参构造
        this.deptno = deptno;        this.dname = dname;        this.loc = loc;
    }    //setter方法
    public void setDeptno(int d){        this.deptno = d;
    }    public void setDname(String n){        this.dname = n;
    }    public void setLoc(String l){        this.loc = l;
    }    //对象数组的setter方法
    public void setEmp(Emp[] e){        this.emps = e ;
    }    //getter方法
    public int getDeptno(){        return deptno;
    }    public String getDname(){        return dname;
    }    public String getLoc(){        return loc;
    }    //对象数组的getter方法
    public Emp[] getEmp(){        return emps;
    }    //取得完整信息
    public String getInfo(){        return "部门编号：" + this.deptno + "，名称：" + this.dname + "，位置：" + this.loc;
    }

}//员工类class Emp{    private int empno;    private String ename ;    private String job ;    private double sal;    private double comm ;    private Dept dept;//“引用关系” 在雇员里面保存部门信息

    private Emp mgr;//“引用关系” 在雇员里面设置领导信息

    public Emp(){//无参构造
    }    public Emp(int empno,String ename, String job, double sal, double comm){//有参构造
        this.empno = empno;        this.ename = ename ;        this.job = job;        this.sal = sal ;        this.comm = comm ;
    }    //setter方法
    public void setEmpno(int e){        this.empno = e;
    }    public void setEname(String n){        this.ename = n ;
    }    public void setJob(String j){        this.job = j ;
    }    public void setSal(double s){        this.sal = s ;
    }    public void setComm(double c){        this.comm = c ;
    }    public void setMgr(Emp m){        this.mgr = m;
    }    public void setDept(Dept d){        this.dept = d;
    }    //getter方法
    public int getEmpno(){        return empno;
    }    public String getEname(){        return ename;
    }    public String getJbo(){        return job;
    }    public double getSal(){        return sal;
    }    public double getComm(){        return comm;
    }    public Emp getMgr(){        return mgr;
    }    public Dept getDept(){        return dept;
    }    public String getInfo(){//取得完整信息
        return "雇员编号：" + this.empno + "，姓名：" + this.ename + "，职位：" + this.job + "，工资：" + this.sal + "，佣金：" + this.comm ;
    }
}//测试类，设置数据并取出public class TestDemo {

    public static void main(String[] args) {        // 产生各自的独立对象，设置数据
        Dept dept = new Dept(10,"ACCOUNTING","New York");
        Emp ea = new Emp(1234,"Yiyao","CLERK",900.0,0.0);
        Emp eb = new Emp(1235,"Acan", "MANAGER",4000.0,9.0);
        Emp ec = new Emp(1236,"Dramatic","PRESIDENT",9000.0,80.0);        //设置雇员和领导关系
        ea.setMgr(eb);
        eb.setMgr(ec);        //设置雇员和部门关系
        ea.setDept(dept);
        eb.setDept(dept);
        ec.setDept(dept);        //部门与雇员
        dept.setEmp(new Emp[]{ea,eb,ec});        //取得数据
        System.out.println(ea.getInfo());
        System.out.println("\t|-" + ea.getMgr().getInfo());
        System.out.println("\t|-" + ea.getDept().getInfo());

        System.out.println("-----------------------------------------");//分割线

        System.out.println(dept.getInfo());        for(int x = 0; x < dept.getEmp().length; x++){
            System.out.println("\t|-" + dept.getEmp()[x].getInfo());            if(dept.getEmp()[x].getMgr() != null){
                System.out.println("\t\t|-" + dept.getEmp()[x].getMgr().getInfo());
            }
        }

    }

}

//部门类class Dept{    private int deptno;//部门编号
    private String dname;//部门名称
    private String loc;//部门位置

    private Emp emps[];//“引用关系” 多个雇员,描述多这个概念应该使用对象数组进行完成

    //明确定义一个无参构造
    public Dept(){      
    }    public Dept(int deptno,String dname,String loc){//有参构造
        this.deptno = deptno;        this.dname = dname;        this.loc = loc;
    }    //setter方法
    public void setDeptno(int d){        this.deptno = d;
    }    public void setDname(String n){        this.dname = n;
    }    public void setLoc(String l){        this.loc = l;
    }    //对象数组的setter方法
    public void setEmp(Emp[] e){        this.emps = e ;
    }    //getter方法
    public int getDeptno(){        return deptno;
    }    public String getDname(){        return dname;
    }    public String getLoc(){        return loc;
    }    //对象数组的getter方法
    public Emp[] getEmp(){        return emps;
    }    //取得完整信息
    public String getInfo(){        return "部门编号：" + this.deptno + "，名称：" + this.dname + "，位置：" + this.loc;
    }

}//员工类class Emp{    private int empno;    private String ename ;    private String job ;    private double sal;    private double comm ;    private Dept dept;//“引用关系” 在雇员里面保存部门信息

    private Emp mgr;//“引用关系” 在雇员里面设置领导信息

    public Emp(){//无参构造
    }    public Emp(int empno,String ename, String job, double sal, double comm){//有参构造
        this.empno = empno;        this.ename = ename ;        this.job = job;        this.sal = sal ;        this.comm = comm ;
    }    //setter方法
    public void setEmpno(int e){        this.empno = e;
    }    public void setEname(String n){        this.ename = n ;
    }    public void setJob(String j){        this.job = j ;
    }    public void setSal(double s){        this.sal = s ;
    }    public void setComm(double c){        this.comm = c ;
    }    public void setMgr(Emp m){        this.mgr = m;
    }    public void setDept(Dept d){        this.dept = d;
    }    //getter方法
    public int getEmpno(){        return empno;
    }    public String getEname(){        return ename;
    }    public String getJbo(){        return job;
    }    public double getSal(){        return sal;
    }    public double getComm(){        return comm;
    }    public Emp getMgr(){        return mgr;
    }    public Dept getDept(){        return dept;
    }    public String getInfo(){//取得完整信息
        return "雇员编号：" + this.empno + "，姓名：" + this.ename + "，职位：" + this.job + "，工资：" + this.sal + "，佣金：" + this.comm ;
    }
}//测试类，设置数据并取出public class TestDemo {

    public static void main(String[] args) {        // 产生各自的独立对象，设置数据
        Dept dept = new Dept(10,"ACCOUNTING","New York");
        Emp ea = new Emp(1234,"Yiyao","CLERK",900.0,0.0);
        Emp eb = new Emp(1235,"Acan", "MANAGER",4000.0,9.0);
        Emp ec = new Emp(1236,"Dramatic","PRESIDENT",9000.0,80.0);        //设置雇员和领导关系
        ea.setMgr(eb);
        eb.setMgr(ec);        //设置雇员和部门关系
        ea.setDept(dept);
        eb.setDept(dept);
        ec.setDept(dept);        //部门与雇员
        dept.setEmp(new Emp[]{ea,eb,ec});        //取得数据
        System.out.println(ea.getInfo());
        System.out.println("\t|-" + ea.getMgr().getInfo());
        System.out.println("\t|-" + ea.getDept().getInfo());

        System.out.println("-----------------------------------------");//分割线

        System.out.println(dept.getInfo());        for(int x = 0; x < dept.getEmp().length; x++){
            System.out.println("\t|-" + dept.getEmp()[x].getInfo());            if(dept.getEmp()[x].getMgr() != null){
                System.out.println("\t\t|-" + dept.getEmp()[x].getMgr().getInfo());
            }
        }

    }

}

Related articles:

A simple example of converting Java basic byte[] to various data types

Look at implicit conversions in MySQL and Oracle from Java type conversion

The above is the detailed content of Data table and simple Java conversion _A practical case of reference relationship. For more information, please follow other related articles on the PHP Chinese website!