重點內(nèi)容IoC和AOP

Spring

Spring是分層的 Java SE/EE應(yīng)用 full-stack 輕量級開源框架作儿，以 IoC（Inverse Of Control：反轉(zhuǎn)控制）和 AOP（Aspect Oriented Programming：面向切面編程）為內(nèi)核伴逸，提供了展現(xiàn)層 SpringMVC 和持久層 Spring JDBC 以及業(yè)務(wù)層事務(wù)管理等眾多的企業(yè)級應(yīng)用技術(shù)，還能整合開源世界眾多著名的第三方框架和類庫维蒙，逐漸成為使用最多的Java EE 企業(yè)應(yīng)用開源框架
spring 的體系結(jié)構(gòu)

編寫XML 配置spring賬戶轉(zhuǎn)賬案例
實體類Account .java

package com.neusoft.domain;

import java.io.Serializable;

/**
 * @author Eric Lee
 * @date 2020/9/5 11:01
 */
public class Account implements Serializable {
    private Integer id;
    private String name;
    private Float 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 Float getMoney() {
        return money;
    }

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

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

Dao

package com.neusoft.dao;

import com.neusoft.domain.Account;

import java.util.List;

public interface IAccountDao {

    List<Account> findAllAccount();

    Account findAccountById(Integer accountId);

    void saveAccount(Account account);

    void updateAccount(Account account);

    void deleteAccount(Integer accountId);

}

impl

package com.neusoft.dao.Impl;

import com.neusoft.dao.IAccountDao;
import com.neusoft.domain.Account;
import org.apache.commons.dbutils.QueryRunner;
import org.apache.commons.dbutils.handlers.BeanHandler;
import org.apache.commons.dbutils.handlers.BeanListHandler;

import java.sql.SQLException;
import java.util.List;

/**
 * @author Eric Lee
 * @date 2020/9/5 11:10
 */
public class AccountDaoImpl  implements IAccountDao {

    private QueryRunner runner;

    public void setRunner(QueryRunner runner) {
        this.runner = runner;
    }

    @Override
    public List<Account> findAllAccount() {
        try {
            return runner.query("select * from account", new BeanListHandler<Account>(Account.class));
        } catch (SQLException e) {
            throw new RuntimeException(e);
        }
    }

    @Override
    public Account findAccountById(Integer accountId) {
        try {
            return runner.query("select * from account where id = ?", new BeanHandler<Account>(Account.class), accountId);
        } catch (SQLException e) {
            throw new RuntimeException(e);
        }
    }

    @Override
    public void saveAccount(Account account) {
        try {
            runner.update("insert into account(name,money) values (?, ?)",account.getName(), account.getMoney());
        } catch (SQLException e) {
            throw new RuntimeException(e);
        }
    }

    @Override
    public void updateAccount(Account account) {

        try {
            runner.update("update account set name= ? , money = ? where id=? ",account.getName(), account.getMoney(), account.getId());
        } catch (SQLException e) {
            throw new RuntimeException(e);
        }

    }

    @Override
    public void deleteAccount(Integer accountId) {

        try {
            runner.update("delete from account where id = ?", accountId);
        } catch (SQLException e) {
            throw new RuntimeException(e);
        }

    }
}

bean.xml

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xsi:schemaLocation="http://www.springframework.org/schema/beans
        http://www.springframework.org/schema/beans/spring-beans.xsd">
<!--    配置service-->
    <bean id="accountService" class="com.neusoft.service.impl.AccountServiceImpl">
        <property name="accountDao" ref="accountDao"></property>
    </bean>
<!--    配置dao-->
    <bean id="accountDao" class="com.neusoft.dao.Impl.AccountDaoImpl">
<!--        注入qr-->
        <property name="runner" ref="runner"></property>
    </bean>

<!--    配置QueryRunner-->

    <bean id="runner" class="org.apache.commons.dbutils.QueryRunner">
<!--        注入數(shù)據(jù)源-->
        <constructor-arg name="ds" ref="dataSource"></constructor-arg>
    </bean>

    <!--    配置數(shù)據(jù)源-->
    <bean id="dataSource" class="com.mchange.v2.c3p0.ComboPooledDataSource">
        <property name="driverClass" value="com.mysql.jdbc.Driver"></property>
        <property name="jdbcUrl" value="jdbc:mysql://localhost:3306/java9_spring"></property>
        <property name="user" value="root"></property>
        <property name="password" value="root"></property>

    </bean>

</beans>

service

package com.neusoft.service;

import com.neusoft.domain.Account;

import java.util.List;

public interface IAccountService {

    // 查詢所有
    List<Account> findAllAccount();

    Account findAccountById(Integer accountId);

    void  saveAccount(Account account);

    void  updateAccount(Account account);

    void deleteAccount(Integer accountId);

}

實現(xiàn)

package com.neusoft.service.impl;

import com.neusoft.dao.IAccountDao;
import com.neusoft.dao.Impl.AccountDaoImpl;
import com.neusoft.domain.Account;
import com.neusoft.service.IAccountService;

import java.util.List;

/**
 * @author Eric Lee
 * @date 2020/9/5 11:39
 */
public class AccountServiceImpl implements IAccountService {
    private IAccountDao accountDao;

    public void setAccountDao(IAccountDao accountDao) {
        this.accountDao = accountDao;
    }

    @Override
    public List<Account> findAllAccount() {
        return accountDao.findAllAccount();
    }

    @Override
    public Account findAccountById(Integer accountId) {
        return accountDao.findAccountById(accountId);
    }

    @Override
    public void saveAccount(Account account) {
        accountDao.saveAccount(account);
    }

    @Override
    public void updateAccount(Account account) {
        accountDao.updateAccount(account);
    }

    @Override
    public void deleteAccount(Integer accountId) {
            accountDao.deleteAccount(accountId);
    }
}

Test

package com.neusoft.test;

import com.neusoft.domain.Account;
import com.neusoft.service.IAccountService;
import org.junit.Test;
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;

import java.util.List;

/**
 * @author Eric Lee
 * @date 2020/9/5 14:09
 */
public class TestAccountService {

    ApplicationContext ac = new ClassPathXmlApplicationContext("bean.xml");
    IAccountService as = ac.getBean("accountService", IAccountService.class);

    @Test
    public void testFindAll() {

        //3.執(zhí)行方法
        List<Account> accounts = as.findAllAccount();
        for(Account account : accounts){
            System.out.println(account);
        }
    }

    @Test
    public void testFindOne() {
        //3.執(zhí)行方法
        Account account = as.findAccountById(1);
        System.out.println(account);
    }

    @Test
    public void testSave() {
        Account account = new Account();
        account.setName("test");
        account.setMoney(12345f);
        //3.執(zhí)行方法
        as.saveAccount(account);

    }

    @Test
    public void testUpdate() {
        //3.執(zhí)行方法
        Account account = as.findAccountById(4);
        account.setMoney(23456f);
        as.updateAccount(account);
    }

    @Test
    public void testDelete() {
        //3.執(zhí)行方法
        as.deleteAccount(4);
    }
}

使用注解進行配置

bean.xml

<?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">

    <context:component-scan base-package="com.neusoft">

    </context:component-scan>
<!--    配置QueryRunner-->

    <bean id="runner" class="org.apache.commons.dbutils.QueryRunner">
<!--        注入數(shù)據(jù)源-->
        <constructor-arg name="ds" ref="dataSource"></constructor-arg>
    </bean>

    <!--    配置數(shù)據(jù)源-->
    <bean id="dataSource" class="com.mchange.v2.c3p0.ComboPooledDataSource">
        <property name="driverClass" value="com.mysql.jdbc.Driver"></property>
        <property name="jdbcUrl" value="jdbc:mysql://localhost:3306/java9_spring"></property>
        <property name="user" value="root"></property>
        <property name="password" value="root"></property>

    </bean>

</beans>

核心修改
將對象交給spring去管理，指定掃描的包名

 <context:component-scan base-package="com.neusoft">
 </context:component-scan>

service層

image

dao層

image

@Component

image

作用
把資源讓 spring 來管理果覆。相當于在 xml 中配置一個 bean颅痊。
屬性
value：指定 bean 的 id。如果不指定 value 屬性局待，默認 bean 的 id 是當前類的類名斑响。首字母小寫菱属。

@Controller @Service @Repository

他們?nèi)齻€注解都是針對一個的衍生注解，他們的作用及屬性都是一模一樣的舰罚。
他們只不過是提供了更加明確的語義化纽门。
@Controller ：一般用于表現(xiàn)層的注解。
@Service ：一般用于業(yè)務(wù)層的注解营罢。
@Repository ：一般用于持久層的注解
細節(jié)：如果注解中有且只有一個屬性要賦值時是赏陵，且名稱是 value ，value 在賦值是可以不寫

@Autowired

作用：自動按照類型注入饲漾。當使用注解注入屬性時蝙搔，set方法可以省略。它只能注入其他 bean 類型能颁。當有多個類型匹配時杂瘸，使用要注入的對象變量名稱作為 bean 的 id，在 spring 容器查找伙菊，找到了也可以注入成功败玉。找不到就報錯。
相當于： <property name="accountDao" ref="accountDao"></property>