Java基础阶段项目练习总结（持续更新中）
作者：互联网
2022.01.19项目三：开发人员调度软件
通过项目是复习知识的最好方式，写项目的过程中多思考多总结，多看优秀代码，多练习，编程能力才能真正提高。
设计概览
问题①：在写NameListService的构造器时，给employees数组添加元素时直接使用了属性.set方法的方式，应当使用构造器。
问题②：在写NameListService的构造器中的逻辑时，使用了if-else结构导致代码比较复杂和混乱，这里最好使用switch-case的方式
以下是正确代码：
package www.fancy.team.service;
import www.fancy.team.domain.*;
import static www.fancy.team.service.Data.*;
public class NameListService {
private Employee[] employees;
public NameListService() {
employees = new Employee[Data.EMPLOYEES.length];
for (int i = 0; i < employees.length; i++) {
int type = Integer.parseInt(Data.EMPLOYEES[i][0]);
int id = Integer.parseInt(EMPLOYEES[i][1]);
String name = EMPLOYEES[i][2];
int age = Integer.parseInt(EMPLOYEES[i][3]);
double salary = Double.parseDouble(EMPLOYEES[i][4]);
Equipment eq;
double bonus;
int stock;
switch (type) {//问题②
case EMPLOYEE:
employees[i] = new Employee(id, name, age, salary);//问题①
break;
case PROGRAMMER:
eq = createEquipment(i);
employees[i] = new Programmer(id, name, age, salary, eq);
case DESIGNER:
eq = createEquipment(i);
bonus = Double.parseDouble(EMPLOYEES[i][5]);
employees[i] = new Designer(id, name, age, salary, eq, bonus);
case ARCHITECT:
eq = createEquipment(i);
bonus = Double.parseDouble(EMPLOYEES[i][5]);
stock = Integer.parseInt(EMPLOYEES[i][6]);
employees[i] = new Architect(id, name, age, salary, eq, bonus, stock);
}
}
}
private Equipment createEquipment(int j) {
int type = Integer.parseInt(EQIPMENTS[j][0]);
switch (type) {
case PC:
return new PC(EQIPMENTS[j][1], EQIPMENTS[j][2]);
case NOTEBOOK:
return new NoteBook(EQIPMENTS[j][1], Integer.parseInt(EQIPMENTS[j][2]));
case PRINTER:
return new Printer(EQIPMENTS[j][1], EQIPMENTS[j][2]);
}
return null;
}
/**
* @return 2022/1/19
* @Name getAllEmployee
* @Description 获取当前所有员工
* @Author Fancy
* @Version 1.0
*/
public Employee[] getAllEmployee() {
return employees;
}
public Employee getEmployee(int id) throws TeamException {
for (int i = 0; i < employees.length; i++) {
if (employees[i].getId() == id) {
return employees[i];
}
}
throw new TeamException("找不到指定的员工");
}
}
问题③：在写TeamService的getTeam方法来获取当前团队的所有对象时，疑惑为什么不直接return team；
原因是固定长度为5的team不一定被填满，后续对数组进行操作时有可能造成空指针异常。
问题④：在写addMember()方法（向团队中添加成员）时，对多条添加失败的原因进行代码实现时只使用if_else if的结构，导致逻辑理不清，应采用if和if_else if结合来写
问题⑤：在使用equals方法时，写法需要优化一下
问题⑥：没有想到用throw来抛出异常
package www.fancy.team.service;
import www.fancy.team.domain.Employee;
import www.fancy.team.domain.Programmer;
public class TeamService {
private static int counter =1;
private final int MAX_MEMBER = 5;
private Programmer[] team = new Programmer[MAX_MEMBER];
private int total = 0;
public Programmer[] getTeam(){
Programmer[] team = new Programmer[total];
for (int i = 0; i < total; i++) {
team[i] = this.team[i];
}
return team;
}
public void addMember(Employee e){
/*
成员已满，无法添加
该成员不是开发人员，无法添加
该员工已在本开发团队中
该员工已是某团队成员
该员正在休假，无法添加
团队中至多只能有一名架构师
团队中至多只能有两名设计师
团队中至多只能有三名程序员
*/
//成员已满，无法添加
boolean isFlag1 = false;
for(int i=0;i<total;i++){
if(team[i].getId() == e.getId()){
isFlag1 = true;
return;
}
}
if(total == 5){
System.out.println("成员已满，无法添加");
}else if(e.getClass().getName() == "Employee"){
System.out.println("该成员不是开发人员，无法添加");
}else if( isFlag1 == true){
System.out.println("该员工已在本开发团队中");//问题④、⑥
}
Programmer p = (Programmer) e;
if(p.getStatus().getNAME().equals("BUSY")){ //最好写为"BUSY".equals(p.getStatus().getNAME())//问题⑤
}
}
}
正确代码：
package com.atguigu.team.service;
import com.atguigu.team.domain.*;
public class TeamService {
private static int counter = 1;//用于自动生成团队成员的memberId
private final int MAX_MEMBER = 5;//团队人数上限
private Programmer[] team = new Programmer[MAX_MEMBER];//保存当前团队成员
private int total = 0;//团队实际人数
public TeamService() {
}
//返回team中所有程序员构成的数组
public Programmer[] getTeam() {
Programmer[] team = new Programmer[total];
for (int i = 0; i < total; i++) {
team[i] = this.team[i];
}
return team;
}
public void addMember(Employee e) throws TeamException {
if (total >= MAX_MEMBER)
throw new TeamException("成员已满，无法添加");
if (!(e instanceof Programmer))
throw new TeamException("该成员不是开发人员，无法添加");
Programmer p = (Programmer)e;
if (isExist(p))
throw new TeamException("该员工已在本团队中");
if(p.getStatus().getNAME().equals("BUSY")) {
throw new TeamException("该员工已是某团队成员");
}else if(p.getStatus().getNAME().equals("VOCATION")) {
throw new TeamException("该员正在休假，无法添加");
}
// switch (p.getStatus()) {
// case BUSY :throw new TeamException("该员工已是某团队成员");
// case VOCATION:throw new TeamException("该员正在休假，无法添加");
// }
int numOfArch = 0, numOfDsgn = 0, numOfPrg = 0;
for (int i = 0; i < total; i++) {
if (team[i] instanceof Architect) numOfArch++;
else if (team[i] instanceof Designer) numOfDsgn++;
else if (team[i] instanceof Programmer) numOfPrg++;
}
if (p instanceof Architect) {
if (numOfArch >= 1) throw new TeamException("团队中至多只能有一名架构师");
} else if (p instanceof Designer) {
if (numOfDsgn >= 2) throw new TeamException("团队中至多只能有两名设计师");
} else if (p instanceof Programmer) {
if (numOfPrg >= 3) throw new TeamException("团队中至多只能有三名程序员");
}
//添加到数组
p.setStatus(Status.BUSY);
p.setMemberId(counter++);
team[total++] = p;
}
private boolean isExist(Programmer p) {
for (int i = 0; i < total; i++) {
if (team[i].getId() == p.getId()) return true;
}
return false;
}
//删除指定memberId的程序员
public void removeMember(int memberId) throws TeamException {
int n = 0;
//找到指定memberId的员工，并删除
for (; n < total; n++) {
if (team[n].getMemberId() == memberId) {
team[n].setStatus(Status.FREE);
break;
}
}
//如果遍历一遍，都找不到，则报异常
if (n == total)
throw new TeamException("找不到该成员，无法删除");
//后面的元素覆盖前面的元素
for (int i = n + 1; i < total; i++) {
team[i - 1] = team[i];
}
team[--total] = null;
}
}
标签：总结,Java,int,练习,TeamException,team,new,Programmer,total 来源： https://www.cnblogs.com/fancy2022/p/15824785.html