dbutils的環境搭建以及使用

DBUtils的簡單實現方式

第一步、創建Java工程【此處使用的是maven工程】並導入jar包

<!--導入mysql數據庫驅動-->
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <version>5.1.46</version>
        </dependency>
        <!--導入dbutils包-->
        <dependency>
            <groupId>commons‐dbutils</groupId>
            <artifactId>commons‐dbutils</artifactId>
            <version>1.6</version>
        </dependency>
        <!--導入連接池包-->
        <dependency>
            <groupId>c3p0</groupId>
            <artifactId>c3p0</artifactId>
            <version>0.9.1.2</version>
        </dependency>
        <!--導入spring包-->
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-context</artifactId>
            <version>5.1.5.RELEASE</version>
        </dependency>
        <!--導入junit包用於測試-->
        <dependency>
            <groupId>junit</groupId>
            <artifactId>junit</artifactId>
            <version>4.12</version>
        </dependency>

第二步、創建數據庫

CREATE TABLE `account` (
  `id` int(11) NOT NULL AUTO_INCREMENT,
  `name` varchar(40) DEFAULT NULL,
  `money` float DEFAULT NULL,
  PRIMARY KEY (`id`)
) ENGINE=InnoDB AUTO_INCREMENT=11 DEFAULT CHARSET=utf8

第三步、創建JavaBean(又稱Pojo對象)

public class Account {
   private Integer id;
   private String name;
   private Double money;

    public Integer getId() {
        return id;
    }

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

    public String getName() {
        return name;
    }

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

    public Double getMoney() {
        return money;
    }

    public void setMoney(Double money) {
        this.money = money;
    }

    @Override
    public String toString() {
        return "Account{" +
                "id=" + id +
                ", name='" + name + '\'' +
                ", money=" + money +
                '}';
    }
}

第四步、創建Dao接口

import java.util.List;

public interface AccountDao {

    public Account findById(Integer id);

    public List<Account> findAll();

    public void save(Account account);

    public void update(Account account);

    public void deleteById(Integer id);

}

第五步、編寫實現類

public class AccountDaoImp implements AccountDao{


    private QueryRunner queryRunner;

    //依賴注入
    public void setQueryRunner(QueryRunner queryRunner){
        this.queryRunner=queryRunner;
    }

    @Override
    public Account findById(Integer id) {
        Account account=new Account();
        //此處要求如下
        //第二個 參數是頂級接口ResultSetHandler的實現類
        // 如果返回一個對象用BeanResultSetHandler
        //如果返回多個對象使用BeanListHandler
        //要求數據庫字段和實體類字段要要一致
        //如果不一致需要實現ResultSetHandler接口
        try{
        account=queryRunner.query("select * from account where id= ?",new BeanHandler<Account>(Account.class),id);
        }        catch (Exception e){
            e.printStackTrace();
        }
        return account;
    }

    @Override
    public List<Account> findAll() {
        List<Account> list=new ArrayList<>();
        try{
            list=queryRunner.query("select * from account where id= ?",new BeanListHandler<Account>(Account.class));
        }        catch (Exception e){
            e.printStackTrace();
        }
        return list;
    }

    @Override
    public void save(Account account) {

    }

    @Override
    public void update(Account account) {

    }

    @Override
    public void deleteById(Integer id) {

    }
}

第六步、測試

使用Junit調用實現類進行測試！

DBUtils的Spring下的使用

前四步相同，下面從第五步開始

第五步、編寫Spring配置文件

<?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:aop="http://www.springframework.org/schema/aop"
       xmlns:context="http://www.springframework.org/schema/context"
       xmlns:tx="http://www.springframework.org/schema/tx"
       xmlns:mvc="http://www.springframework.org/schema/mvc"
       xsi:schemaLocation="http://www.springframework.org/schema/beans
          http://www.springframework.org/schema/beans/spring-beans-4.3.xsd
          http://www.springframework.org/schema/aop
          http://www.springframework.org/schema/aop/spring-aop-4.3.xsd
          http://www.springframework.org/schema/context
          http://www.springframework.org/schema/context/spring-context-4.3.xsd
          http://www.springframework.org/schema/mvc
          http://www.springframework.org/schema/mvc/spring-mvc-4.3.xsd
          http://www.springframework.org/schema/tx
          http://www.springframework.org/schema/tx/spring-tx-4.3.xsd">

    <!--    把dataSource交給IOC容器-->
    <bean id="dataSource" class="com.mchange.v2.c3p0.ComboPooledDataSource">
        <property name="driverClass" value="com.mysql.jdbc.Driver"/>
        <property name="jdbcUrl" value="jdbc:mysql:///mybatis"/>
        <property name="user" value="root"/>
        <property name="password" value="root"/>
    </bean>

    <!--    把queryRunner對象交給IOC容器-->
    <bean id="queryRunner" class="org.apache.commons.dbutils.QueryRunner">
        <constructor-arg name="ds" ref="dataSource"/>
    </bean>

    <!--    為accountDao注入依賴-->
    <bean id="accountDao" class="AccountDaoImp">
        <property name="queryRunner" ref="queryRunner"/>
    </bean>

　　<!-- 把實現類對象交給IOC容器--> <bean id="" class=""> <constructor-arg name="ds" ref="dataSource"/> </bean>

</beans>

第六步、編寫實現類

在實現類中通過從IOC容器獲取對象就可以

第七步、測試