学习流程-2024-11

学习流程2024-11-15：

1.如何理解springboot项目，将.html资源文件放在resources/templates文件夹下？

分析：这是一种“约定大于配置”。一般将.html模版文件放在resouces/templates文件夹下。

2.那将图片文件、css文件、js文件等分别放到单独的文件夹，然后再把文件夹放到resources/images文件夹下，也是springboot的约定大于配置是吧？

分析：是的。

学习流程2024-11-23：

1.问题：idea直接创建springboot项目时jdk最低要求17。

解决方法：在idea新建springboot项目时spring initializr选项卡将server url由https://start.spring.io改为https://start.aliyun.com

补充：新建项目时依赖里，选web、devtools（用于热部署）、lombok。

学习流程2024-11-27：

1.流程：

1.1maven下载完依赖后删掉项目文件夹结构里没用的maven、git相关：.mvn文件夹、.gitignore、mvnw、mvnw.cmd、HELP.md文件。

学习流程2024-11-28：

/**
 * @RestController声明返回的不应被解释为视图名
 *
 * @author konglingchao
 * @Description:
 * @date 2024/11/28
 */
@RestController
public class HelloController {
    @GetMapping("/hello")
    public String hello() {
        return "hello, world";
    }
}

运行项目，浏览器访问localhost:8086/hello，(8086是自己配的端口），页面成功显示"hello, world"。

@Data
@AllArgsConstructor
@NoArgsConstructor
public class Department {
    private Integer id;
    private String departmentName;
}

public class DepartmentDao {
    private static Map<Integer, Department> departments = null;
    
    static {
        departments = new HashMap<>();
        departments.put(101, new Department(101, "教学部"));
        departments.put(102, new Department(102, "市场部"));
        departments.put(103, new Department(103, "教研部"));
        departments.put(104, new Department(104, "运营部"));
        departments.put(105, new Department(105, "后勤部"));
    }

    public Collection<Department> getDepartments() {
        return departments.values();
    }

    public Department getDepartmentById(Integer id) {
        return departments.get(id);
    }
}

学习流程2024-11-29：

@Data
@NoArgsConstructor
public class Employee {
    private Integer id;
    private String lastName;
    private String email;
    private String gender; // M：男male /meɪl/；F：女female /ˈfiː.meɪl/
    private Department department;
    private Date birth;

    public Employee(Integer id, String lastName, String email, String gender, Department department) {
        this.id = id;
        this.lastName = lastName;
        this.email = email;
        this.gender = gender;
        this.department = department;
        // 仅用于测试
        this.birth = new Date();
    }
}

学习流程2024-11-30：

public class EmployeeDao {
    @Autowired
    private DepartmentDao departmentDao;

    private static Map<Integer, Employee> employees = null;

    static {
        employees = new HashMap<Integer, Employee>();
        employees.put(1001, new Employee(1001, "AA", "A24734673@qq.com", "M", new Department(101, "教学部")));
        employees.put(1002, new Employee(1002, "BB", "B24734673@qq.com", "F", new Department(102, "市场部")));
        employees.put(1003, new Employee(1003, "CC", "C24734673@qq.com", "M", new Department(103, "教研部")));
        employees.put(1004, new Employee(1004, "DD", "D24734673@qq.com", "F", new Department(104, "运营部")));
        employees.put(1005, new Employee(1005, "EE", "E24734673@qq.com", "M", new Department(105, "后勤部")));
    }

    /**
     * 初始id，主键自增
     */
    private int initId = 1006;

    /**
     * 新增雇员
     */
    public int addEmployee(Employee employee) {
        if (StringUtils.isEmpty(employee.getId())) {
            employee.setId(initId++);
        }
        employee.setDepartment(departmentDao.getDepartmentById(employee.getDepartment().getId()));
        employees.put(employee.getId(), employee);
        return 1;
    }

    /**
     * 删除雇员
     */
    public int deleteEmployee(int id) {
        if (employees.containsKey(id)) {
            employees.remove(id);
            return 1;
        } else {
            return 0;
        }
    }

    /**
     * 修改雇员
     */
    public int updateEmployee(Employee employee) {
        int id = employee.getId();
        if (employees.containsKey(id)) {
            employee.setDepartment(departmentDao.getDepartmentById(employee.getDepartment().getId()));
            employees.put(id, employee);
            return 1;
        } else {
            return 0;
        }
    }

    /**
     * 通过id查询雇员
     */
    public Employee getEmployeeById(int id) {
        return employees.get(id);
    }

    /**
     * 获取所有雇员
     */
    public Collection<Employee> getAllEmployees() {
        return employees.values();
    }
}