使用 Spring JDBC 的聚合

Question

我正在学习 Spring JDBC 插入数据库，但我无法将我的 2 个聚合 class 插入到一起。（地址为 class 的员工）。如何将 Address class' 变量添加到 Employee table？代码如下，谢谢。

Employee.java

package model;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.beans.factory.annotation.Qualifier;

public class Employee {

private int id;
private String name;
private String surname;
private int age;
private String gender;
private String contact;

public Employee(int id, String name, String surname, int age, String gender, String contact, Address address) {
    super();
    this.id = id;
    this.name = name;
    this.surname = surname;
    this.age = age;
    this.gender = gender;
    this.contact = contact;
    this.address = address;
}


private Address address;

public int getId() {
    return id;
}

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

public String getName() {
    return name;
}

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

public String getSurname() {
    return surname;
}

public void setSurname(String surname) {
    this.surname = surname;
}

public int getAge() {
    return age;
}

public void setAge(int age) {
    this.age = age;
}

public String getGender() {
    return gender;
}

public void setGender(String gender) {
    this.gender = gender;
}

public String getContact() {
    return contact;
}

public void setContact(String contact) {
    this.contact = contact;
}

public Address getAddress() {
    return address;
}

public void setAddress(Address address) {
    this.address = address;
}

@Override
public String toString() {
    return "Employee [id=" + id + ", name=" + name + ", surname=" + surname + ", age=" + age + ", gender=" + gender
            + ", contact=" + contact + ", address=" + address + "]";
}

}

Address.java

package model;

public class Address {
    private String address;
    private String city;
    private String country;

    public Address(String address, String city, String country) {
        super();
        this.address = address;
        this.city = city;
        this.country = country;
    }

    public String getAddress() {
        return address;
    }

    public void setAddress(String address) {
        this.address = address;
    }

    public String getCity() {
        return city;
    }

    public void setCity(String city) {
        this.city = city;
    }

    public String getCountry() {
        return country;
    }

    public void setCountry(String country) {
        this.country = country;
    }

    @Override
    public String toString() {
        return "[" + address + ", city=" + city + ", country=" + country + "]";
    }

}

EmployeeDAO.java

package dao;

import java.sql.SQLException;

import model.Employee;

public interface EmployeeDAO {

    public void saveEmployee(Employee employee) throws Exception;
}

EmployeeDAOImpl.java

package dao;

import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.SQLException;

import javax.sql.DataSource;

import org.springframework.stereotype.Repository;

import model.Employee;


public class EmployeeDAOImpl implements EmployeeDAO {

    private final static String INSERT_EMPLOYEE = "insert into employee (id, name, surname, age, gender, contact) values (?,?,?,?,?,?)";
    private DataSource dataSource;

    public DataSource getDataSource() {
        return dataSource;
    }

    public void setDataSource(DataSource dataSource) {
        this.dataSource = dataSource;
    }

    @Override
    public void saveEmployee(Employee employee) throws SQLException {
        try {
            Connection connection = dataSource.getConnection();
            PreparedStatement preparedStatement = connection.prepareStatement(INSERT_EMPLOYEE);
            preparedStatement.setInt(1, employee.getId());
            preparedStatement.setString(2, employee.getName());
            preparedStatement.setString(3, employee.getSurname());
            preparedStatement.setInt(4, employee.getAge());
            preparedStatement.setString(5, employee.getGender());
            preparedStatement.setString(6, employee.getContact());
            //index 7,8 and 9 are address, city and country...
            preparedStatement.executeUpdate();
            preparedStatement.close();
            System.out.println("Employee is inserted..." + employee);

        } catch (SQLException e) {
            e.printStackTrace();
        }
    }

}

xml 文件

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xmlns:context="http://www.springframework.org/schema/context"
    xsi:schemaLocation="http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans.xsd
http://www.springframework.org/schema/context
http://www.springframework.org/schema/context/spring-context.xsd ">
    <bean
        class="org.springframework.beans.factory.config.PropertyPlaceholderConfigurer">
        <property name="location">
            <value>myconfiguration/jdbc.properties</value>
        </property>
    </bean>
    <bean id="dataSourceId"
        class="org.springframework.jdbc.datasource.DriverManagerDataSource">
        <property name="driverClassName"
            value="${jdbc.driverClassName}" />
        <property name="url" value="${jdbc.url}" />
        <property name="username" value="${jdbc.username}" />
        <property name="password" value="${jdbc.password}" />
    </bean>
    <bean id="employeeDAOImplId" class="dao.EmployeeDAOImpl">
        <property name="dataSource" ref="dataSourceId" />
    </bean>
</beans>

MainTest.java

package test;

import org.springframework.context.support.ClassPathXmlApplicationContext;

import dao.EmployeeDAO;
import model.Employee;

public class MainTest {

    public static void main(String[] args) throws Exception {
        ClassPathXmlApplicationContext context = new ClassPathXmlApplicationContext("EmployeeJDBC.xml");

        EmployeeDAO dao = context.getBean(EmployeeDAO.class);

        Employee employee = new Employee(1, "John", "Doe", 24, "M", "+15555555555", null); // here null, i couldn't fix.
        // Address address = new Address("RandAddress", "RandCity", "RandCountry");

        dao.saveEmployee(employee);

    }
}

Answer 1

根据您的设计，您应该能够向 insert 查询添加适当的列，并更新参数：

// EmployeeDAOImpl

private final static String INSERT_EMPLOYEE = "insert into employee (id, name, surname, age, gender, contact, address, city, country) values (?,?,?,?,?,?,?,?,?)";

// ...
@Override
    public void saveEmployee(Employee employee) throws SQLException {
        try {
            Connection connection = dataSource.getConnection();
            PreparedStatement preparedStatement = connection.prepareStatement(INSERT_EMPLOYEE);
            preparedStatement.setInt(1, employee.getId());
            preparedStatement.setString(2, employee.getName());
            preparedStatement.setString(3, employee.getSurname());
            preparedStatement.setInt(4, employee.getAge());
            preparedStatement.setString(5, employee.getGender());
            preparedStatement.setString(6, employee.getContact());
            //index 7,8 and 9 are address, city and country...
            preparedStatement.setString(7, employee.getAddress().getAddress());
            preparedStatement.setString(8, employee.getAddress().getCity());
            preparedStatement.setString(9, employee.getAddress().getCountry());

            preparedStatement.executeUpdate();
            preparedStatement.close();
            System.out.println("Employee is inserted..." + employee);

        } catch (SQLException e) {
            e.printStackTrace();
        }
    }

并设置MainTest中的字段：

public class MainTest {

    public static void main(String[] args) throws Exception {
        ClassPathXmlApplicationContext context = new ClassPathXmlApplicationContext("EmployeeJDBC.xml");

        EmployeeDAO dao = context.getBean(EmployeeDAO.class);

        Address address = new Address("RandAddress", "RandCity", "RandCountry");
        Employee employee = new Employee(1, "John", "Doe", 24, "M", "+15555555555", address); 

        dao.saveEmployee(employee);

    }
}

使用 Spring JDBC 的聚合

Using aggregation with Spring JDBC

java

jdbc

spring-jdbc