[JAVA Spring] MVC패턴이란?

public class Employee {
    // declaring the variables
    private String EmployeeName;
    private String EmplyeeId;
    private String EmployeeDepartment;

    // defining getter and setter methods
       public String getId() {
          return EmployeeId;
       }

       public void setId(String id) {
          this.EmployeeId = id;
       }

       public String getName() {
          return EmployeeName;
       }

       public void setName(String name) {
          this.EmployeeName = name;
       }

       public String getDepartment() {
              return EmployeeDepartment;
           }

       public void setDepartment(String Department) {
              this.EmployeeDepartment = Department;
           }

}

public class EmployeeView {
    // method to displyay the Employee details
    public vod printEmployeeDetails(String EmployeeName, String EmployeeId, String EmployeeDepartment) {
        System.out.println("Employee Details: ");
        System.out.println("Name: " + EmployeeName);
        System.out.println("Employee ID: " + EmployeeId);
        System.out.println("Employee Department: " + EmployeeDepartment);
    }
}

public class EmplyeeContoller {
    // declaring the variable model and view
    private Employee model;
    private EmployeeView view;

    public EmployeeController(Employee model, Employee view) {
        this.model = model;
        this.view = view;
    }

    public void setEmployeeName(String name) {
        model.setName(name);
    }

    public String getEmployeeName(){
          return model.getName();
    }

    public void setEmployeeId(Stirng id) {
        model.setId(id);
    }

    public void getEmployeeId() {
        return model.getId();
    }

    public void setEmployeeDepartment(String Department){
        model.setDepartment(Department);
    }

    public String getEmployeeDepartment(){
        return model.getDepartment();
    }

    // method to update view
    public void updateView() {
        view.printEmployeeDetails(model.getName(), model.getId(), model.getDepartment())
    }
}

// model data( variables)에 대한 set/get이 이뤄진다.

package com.example.webserver;

import jakarta.annotation.PostConstruct;
import lombok.Getter;
import lombok.extern.slf4j.Slf4j;
import org.springframework.stereotype.Repository;

import java.sql.*;
import java.util.HashMap;

@Getter
@Repository
@Slf4j
public class DataBaseModel {
    private Connection connection;
    private final Object dataBaseLock = new Object();
    private final String url = "jdbc:mariadb://localhost:3306/http";
    private final String user = "root";
    private final String password = "3353";

    @PostConstruct
    public void startConnection() {
        log.info("start connection!!");
        try {
            this.connection = DriverManager.getConnection(url, user, password);
            log.info("connecting success");
        } catch (SQLException e) {
            log.error("<<DataBaseManger>>\n - sql err: " + e.getMessage() + "\n");
        }
    }
    public boolean putText(String key, String value) {
        String sql = "INSERT INTO texts (text_id, text_value) VALUES (?, ?)";

        try {
            PreparedStatement preparedStatement = connection.prepareStatement(sql);
            preparedStatement.setString(1, key);
            preparedStatement.setString(2, value);

            int effectedRows = preparedStatement.executeUpdate();
            preparedStatement.close();

            if (effectedRows > 0) {
                log.info("A new row has been inserted successfully.");
                return true;
            } else {
                log.error("A new row insertion failed");
                return false;
            }
        } catch (SQLException e) {
            log.error("DataBase Manger: putText err: " + e.getMessage());
            return false;
        }
    }

    --- 생략 ---
}

package com.example.webserver;

import lombok.AllArgsConstructor;

import org.springframework.http.HttpStatus;
import org.springframework.http.ResponseEntity;
import org.springframework.web.bind.annotation.*;

import java.time.LocalDateTime;
import java.time.format.DateTimeFormatter;
import java.util.HashMap;

@RestController
@AllArgsConstructor
public class DataController {
    DataBaseModel dataBaseModel;

    @GetMapping("/time")
    public ResponseEntity<String> getTime() {
        LocalDateTime now = LocalDateTime.now();
        String formattedNow = now.format(DateTimeFormatter.ofPattern("yyyy-MM-dd HH:mm:ss"));

        return ResponseEntity.ok(formattedNow);
    }
    @GetMapping("/textall")
    public ResponseEntity<HashMap<String, String>> getTextAll() {
        HashMap<String, String> texts = dataBaseModel.getTextAll();
        if (texts != null && !texts.isEmpty()) {
            return ResponseEntity.ok(texts);
        }
        return ResponseEntity.noContent().build();
    }

    @GetMapping("/text/{id}")
    public ResponseEntity<String> getText(@PathVariable("id") String id) {
        String text = dataBaseModel.getText(id);
        if (text != null) {
            return ResponseEntity.ok(text);
        }
        return ResponseEntity.notFound().build();
    }

    @PostMapping("/text/{id}")
    public ResponseEntity<String> postText(@PathVariable("id") String id, @RequestBody String data) {
        boolean isSaved = dataBaseModel.putText(id, data);
        if (isSaved) {
            return ResponseEntity.status(HttpStatus.CREATED).body("Save successfully");
        }
        return ResponseEntity.status(HttpStatus.SERVICE_UNAVAILABLE).body("Error occurred");
    }

    @DeleteMapping("/text/{id}")
    public ResponseEntity<String> deleteText(@PathVariable("id") String id) {
        boolean isDeleted = dataBaseModel.deleteText(id);
        if (isDeleted) {
            return ResponseEntity.status(HttpStatus.ACCEPTED).body("Delete Successfully");
        }
        return ResponseEntity.notFound().build();
    }

}