Spring笔记6 基于xml的IoC案例（实现CRUD）

https://www.bilibili.com/video/av47952931
p35~37

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数据库部分

mysql中建一张account表

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maven工程

项目结构

pom.xml

<project xmlns="http://maven.apache.org/POM/4.0.0"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0modelVersion>

    <groupId>com.coconutnutgroupId>
    <artifactId>day02_02_account_xmlartifactId>
    <version>1.0-SNAPSHOTversion>

    <packaging>jarpackaging>


    <dependencies>

        <dependency>
            <groupId>org.springframeworkgroupId>
            <artifactId>spring-contextartifactId>
            <version>5.0.2.RELEASEversion>
        dependency>


        <dependency>
            <groupId>commons-dbutilsgroupId>
            <artifactId>commons-dbutilsartifactId>
            <version>1.4version>
        dependency>


        <dependency>
            <groupId>mysqlgroupId>
            <artifactId>mysql-connector-javaartifactId>
            <version>8.0.16version>
        dependency>


        <dependency>
            <groupId>com.mchangegroupId>
            <artifactId>c3p0artifactId>
            <version>0.9.5.2version>
        dependency>


        <dependency>
            <groupId>junitgroupId>
            <artifactId>junitartifactId>
            <version>4.10version>
        dependency>
    dependencies>

project>

实体类

Account.java

package com.cc.domain;

import java.io.Serializable;

/**
 * 账户的实体类
 */
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 +
                '}';
    }
}

业务层

IAccountService.java

package com.cc.service;

import com.cc.domain.Account;

import java.util.List;

/**
 * 账户的业务层接口
 */
public interface IAccountService {

    /**
     * 增
     * @param account
     */
    void createAccount(Account account);

    /**
     * 删
     * @param accountId
     */
    void deleteAccount(Integer accountId);

    /**
     * 改
     * @param account
     */
    void updateAccount(Account account);

    /**
     * 查一个
     * @param accountId
     * @return
     */
    Account retrieveAccountById(Integer accountId);

    /**
     * 查所有
     * @return
     */
    List<Account> retrieveAllAccounts();

}

AccountServiceImpl.java

package com.cc.service.impl;

import com.cc.dao.IAccountDao;
import com.cc.domain.Account;
import com.cc.service.IAccountService;

import java.util.List;

/**
 * 账户的业务层实现类
 */
public class AccountServiceImpl implements IAccountService {

    private IAccountDao accountDao;

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

    public void createAccount(Account account) {
        accountDao.createAccount(account);
    }

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

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

    public Account retrieveAccountById(Integer accountId) {
        return accountDao.retrieveAccountById(accountId);
    }

    public List<Account> retrieveAllAccounts() {
        return accountDao.retrieveAllAccounts();
    }
}

持久层

IAccountDao.java

package com.cc.dao;

import com.cc.domain.Account;

import java.util.List;

/**
 * 账户的持久层接口
 */
public interface IAccountDao {

    void createAccount(Account account);

    void deleteAccount(Integer accountId);

    void updateAccount(Account account);

    Account retrieveAccountById(Integer accountId);

    List<Account> retrieveAllAccounts();

}

AccountDaoImpl.java

package com.cc.dao.impl;

import com.cc.dao.IAccountDao;
import com.cc.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;

/**
 * 账户的持久层实现类
 */
public class AccountDaoImpl implements IAccountDao {

    private QueryRunner runner;

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

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

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

    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);
        }
    }

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

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

}

beans.xml

<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">


    <bean id="accountService" class="com.cc.service.impl.AccountServiceImpl">

        <property name="accountDao" ref="accountDao">property>
    bean>
    

    <bean id="accountDao" class="com.cc.dao.impl.AccountDaoImpl">

        <property name="runner" ref="runner">property>
    bean>
    

    <bean id="runner" class="org.apache.commons.dbutils.QueryRunner" scope="prototype">

        <constructor-arg name="ds" ref="dataSource">constructor-arg>
    bean>


    <bean id="dataSource" class="com.mchange.v2.c3p0.ComboPooledDataSource">

        <property name="driverClass" value="com.mysql.cj.jdbc.Driver">property>
        <property name="jdbcUrl" value="jdbc:mysql://localhost:3306/groot?characterEncoding=utf8">property>
        <property name="user" value="root">property>
        <property name="password" value="iamgroot">property>
    bean>

beans>

测试方法

AccountServiceTest.java

package com.cc.test;

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

import java.util.List;

/**
 * 使用Junit测试配置
 */
public class AccountServiceTest {

    @Test
    public void testCreate(){
        // 1.获取容器
        ApplicationContext ac = new ClassPathXmlApplicationContext("beans.xml");
        // 2.得到业务层对象
        IAccountService as = ac.getBean("accountService",IAccountService.class);
        // 3.执行方法
        Account account = new Account();
        account.setName("ddd");
        account.setMoney(10f);
        as.createAccount(account);
    }

    @Test
    public void testDelete(){
        // 1.获取容器
        ApplicationContext ac = new ClassPathXmlApplicationContext("beans.xml");
        // 2.得到业务层对象
        IAccountService as = ac.getBean("accountService",IAccountService.class);
        // 3.执行方法
        as.deleteAccount(2);
    }

    @Test
    public void testUpdate(){
        // 1.获取容器
        ApplicationContext ac = new ClassPathXmlApplicationContext("beans.xml");
        // 2.得到业务层对象
        IAccountService as = ac.getBean("accountService",IAccountService.class);
        // 3.执行方法
        Account account = as.retrieveAccountById(1);
        account.setMoney(2000f);
        as.updateAccount(account);
    }

    @Test
    public void testRetrieveOne(){
        // 1.获取容器
        ApplicationContext ac = new ClassPathXmlApplicationContext("beans.xml");
        // 2.得到业务层对象
        IAccountService as = ac.getBean("accountService",IAccountService.class);
        // 3.执行方法
        Account account = as.retrieveAccountById(1);

        System.out.println(account);
    }

    @Test
    public void testRetrieveAll(){
        // 1.获取容器
        ApplicationContext ac = new ClassPathXmlApplicationContext("beans.xml");
        // 2.得到业务层对象
        IAccountService as = ac.getBean("accountService",IAccountService.class);
        // 3.执行方法
        List<Account> accounts = as.retrieveAllAccounts();

        for(Account account : accounts){
            System.out.println(account);
        }
    }

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测试

testRetrieveAll()

testRetrieveOne()

testCreate()

testDelete()

testUpdate()

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遇到的bug

执行testRetrieveAll()时

BUG01

警告: Exception encountered during context initialization - cancelling refresh attempt: org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'accountService' defined in class path resource [beans.xml]: Error setting property values; nested exception is org.springframework.beans.NotWritablePropertyException: Invalid property 'accountDao ' of bean class [com.cc.service.impl.AccountServiceImpl]: Bean property 'accountDao ' is not writable or has an invalid setter method. Did you mean 'accountDao'?

org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'accountService' defined in class path resource [beans.xml]: Error setting property values; nested exception is org.springframework.beans.NotWritablePropertyException: Invalid property 'accountDao ' of bean class [com.cc.service.impl.AccountServiceImpl]: Bean property 'accountDao ' is not writable or has an invalid setter method. Did you mean 'accountDao'?

at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.applyPropertyValues(AbstractAutowireCapableBeanFactory.java:1650)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.populateBean(AbstractAutowireCapableBeanFactory.java:1357)
...

其中

Bean property 'accountDao ' is not writable or has an invalid setter method. Did you mean 'accountDao'?

发现多打了个空格

beans.xml中
<property name="accountDao " ref="accountDao">property>
改为
<property name="accountDao" ref="accountDao">property>

改过来之后

BUG02

警告: com.mchange.v2.resourcepool.BasicResourcePool$ScatteredAcquireTask@63fd9b65 -- Acquisition Attempt Failed!!! Clearing pending acquires. While trying to acquire a needed new resource, we failed to succeed more than the maximum number of allowed acquisition attempts (30). Last acquisition attempt exception: 
java.sql.SQLException: Unknown initial character set index '255' received from server. Initial client character set can be forced via the 'characterEncoding' property.
at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:1055)
...

似乎是编码问题

beans.xml中
<property name="jdbcUrl" value="jdbc:mysql://localhost:3306/groot">property>
改为
<property name="jdbcUrl" value="jdbc:mysql://localhost:3306/groot?characterEncoding=utf8">property>

改了之后

BUG03

警告: com.mchange.v2.resourcepool.BasicResourcePool$ScatteredAcquireTask@4879bf70 -- Acquisition Attempt Failed!!! Clearing pending acquires. While trying to acquire a needed new resource, we failed to succeed more than the maximum number of allowed acquisition attempts (30). Last acquisition attempt exception: 
java.sql.SQLException: Unknown system variable 'tx_isolation'
at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:1055)

查一下解决方啊

https://blog.csdn.net/always_younger/article/details/80421783

说是mysql-connector-java版本太低的原因

pom.xml中
<dependency>
	<groupId>mysqlgroupId>
	<artifactId>mysql-connector-javaartifactId>
	<version>5.1.6version>
dependency>
改为
<dependency>
	<groupId>mysqlgroupId>
	<artifactId>mysql-connector-javaartifactId>
	<version>8.0.16version>
dependency>

还有一点小问题

Loading class `com.mysql.jdbc.Driver'. This is deprecated. The new driver class is `com.mysql.cj.jdbc.Driver'. The driver is automatically registered via the SPI and manual loading of the driver class is generally unnecessary.

把过时的类换掉

beans.xml中
<property name="driverClass" value="com.mysql.jdbc.Driver">property>
改为
<property name="driverClass" value="com.mysql.cj.jdbc.Driver">property>

就好了！

Account{id=1, name='aaa', money=1000.0}
Account{id=2, name='bbb', money=1000.0}
Account{id=3, name='ccc', money=1000.0}

Process finished with exit code 0