Spring 基础知识四

本是古典何须时尚 2023-10-10 11:06 7阅读 0赞

**第一 Spring JdbcTemplate**

1.1 JdbcTemplate 概述

spring 框架中提供的一个对象，是对原始 Jdbc API 对象的简单封装

1.2 JdbcTemplate 环境搭建

1.2.1 spring+mysql8 +c3p0 版本基础jar 包依赖：

<dependency>
    			<groupId>org.springframework</groupId>
    			<artifactId>spring-jdbc</artifactId>
    			<version>5.0.2.RELEASE</version>
    		</dependency>
    		<dependency>
    			<groupId>org.springframework</groupId>
    			<artifactId>spring-tx</artifactId>
    			<version>5.0.2.RELEASE</version>
    		</dependency>
    		
    		<dependency>
    			<groupId>c3p0</groupId>
    			<artifactId>c3p0</artifactId>
    			<version>0.9.1.2</version>
    		</dependency>
    		
    		<dependency>
    			<groupId>mysql</groupId>
    			<artifactId>mysql-connector-java</artifactId>
    			<version>8.0.15</version>
    		</dependency>

spring 配置文件(c3p0.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">
    
    	
    	<bean id="jdbcTemplate"
    		class="org.springframework.jdbc.core.JdbcTemplate">
    		<property name="dataSource" ref="dataSource"></property>
    	</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/myblog?useSSL=false&serverTimezone=UTC&allowPublicKeyRetrieval=true"></property>
    		<property name="user" value="root"></property>
    		<property name="password" value="123456"></property>
    	</bean>
    
    </beans>

演示代码:

package com.zzg.jdbc.template.c3p0;
    
    import org.springframework.context.ApplicationContext;
    import org.springframework.context.support.ClassPathXmlApplicationContext;
    import org.springframework.jdbc.core.JdbcTemplate;
    
    public class C3p0Test {
    
    	public static void main(String[] args) {
    		// TODO Auto-generated method stub
    		//1.获取 Spring 容器
    		ApplicationContext ac = new ClassPathXmlApplicationContext("c3p0.xml");
    		//2.根据 id 获取 bean 对象
    		JdbcTemplate jt = (JdbcTemplate) ac.getBean("jdbcTemplate");
    		//3.执行操作
    		jt.execute("insert into blog_tag(name) values ('Java架构')");
    	}
    
    }

1.2.2 spring+mysql8 +DBCP版本基础jar 包依赖：

<dependency>
    			<groupId>org.springframework</groupId>
    			<artifactId>spring-jdbc</artifactId>
    			<version>5.0.2.RELEASE</version>
    		</dependency>
    		<dependency>
    			<groupId>org.springframework</groupId>
    			<artifactId>spring-tx</artifactId>
    			<version>5.0.2.RELEASE</version>
    		</dependency>
    		
    		<dependency>
    			<groupId>org.apache.commons</groupId>
    			<artifactId>commons-dbcp2</artifactId>
    			<version>2.5.0</version>
    		</dependency>
    		<dependency>
    			<groupId>org.apache.commons</groupId>
    			<artifactId>commons-pool2</artifactId>
    			<version>2.6.0</version>
    		</dependency>
    		
    		<dependency>
    			<groupId>mysql</groupId>
    			<artifactId>mysql-connector-java</artifactId>
    			<version>8.0.15</version>
    		</dependency>

spring 配置文件(dbcp.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">
    
    	
    	<bean id="jdbcTemplate"
    		class="org.springframework.jdbc.core.JdbcTemplate">
    		<property name="dataSource" ref="dataSource"></property>
    	</bean>
    
    	
    	<bean id="dataSource"
    		class="org.apache.commons.dbcp2.BasicDataSource">
    		<property name="driverClassName" value="com.mysql.cj.jdbc.Driver"></property>
    		<property name="url" value="jdbc:mysql://localhost:3306/myblog?useSSL=false&serverTimezone=UTC&allowPublicKeyRetrieval=true"></property>
    		<property name="username" value="root"></property>
    		<property name="password" value="123456"></property>
    	</bean>
    
    </beans>

演示代码:

package com.zzg.jdbc.template.dbcp;
    
    import org.springframework.context.ApplicationContext;
    import org.springframework.context.support.ClassPathXmlApplicationContext;
    import org.springframework.jdbc.core.JdbcTemplate;
    
    public class DbcpTest {
    
    	public static void main(String[] args) {
    		// TODO Auto-generated method stub
    		// 1.获取 Spring 容器
    		ApplicationContext ac = new ClassPathXmlApplicationContext("dbcp.xml");
    		// 2.根据 id 获取 bean 对象
    		JdbcTemplate jt = (JdbcTemplate) ac.getBean("jdbcTemplate");
    		// 3.执行操作
    		jt.execute("insert into blog_tag(name) values ('前端架构')");
    	}
    
    }

1.2.3 spring+mysql8 +spring 内置数据源 版本基础jar 包依赖：

依赖jar 文件在此省略

spring 配置文件(basic.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">
    
    	
    	<bean id="jdbcTemplate"
    		class="org.springframework.jdbc.core.JdbcTemplate">
    		<property name="dataSource" ref="dataSource"></property>
    	</bean>
    
    	
    	<bean id="dataSource"
    		class="org.springframework.jdbc.datasource.DriverManagerDataSource">
    		<property name="driverClassName"
    			value="com.mysql.cj.jdbc.Driver"></property>
    		<property name="url" value="jdbc:mysql://localhost:3306/myblog?useSSL=false&serverTimezone=UTC&allowPublicKeyRetrieval=true"></property>
    		<property name="username" value="root"></property>
    		<property name="password" value="123456"></property>
    	</bean>
    
    </beans>

演示代码:

package com.zzg.jdbc.template.basic;
    
    import org.springframework.context.ApplicationContext;
    import org.springframework.context.support.ClassPathXmlApplicationContext;
    import org.springframework.jdbc.core.JdbcTemplate;
    
    public class BasicTest {
    
    	public static void main(String[] args) {
    		// TODO Auto-generated method stub
    		// 1.获取 Spring 容器
    		ApplicationContext ac = new ClassPathXmlApplicationContext("basic.xml");
    		// 2.根据 id 获取 bean 对象
    		JdbcTemplate jt = (JdbcTemplate) ac.getBean("jdbcTemplate");
    		// 3.执行操作
    		jt.execute("insert into blog_tag(name) values ('Java基础知识')");
    	}
    
    }

1.2.4 spring 读取配置文件信息方法(\*.properties)

第一种方式:

定义mysql 数据库连接配置文件(jdbc.properties)

jdbc.driverClass=com.mysql.cj.jdbc.Driver
    jdbc.url=jdbc:mysql://localhost:3306/myblog?useSSL=false&serverTimezone=UTC&allowPublicKeyRetrieval=true
    jdbc.username=root
    jdbc.password=123456

spring 引入外部配置文件

演示实例：

<?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">
    
    	<bean
    		class="org.springframework.beans.factory.config.PropertyPlaceholderConfigurer">
    		<property name="location" value="classpath:jdbc.properties" />
    	</bean>
    
    	
    	<bean id="jdbcTemplate"
    		class="org.springframework.jdbc.core.JdbcTemplate">
    		<property name="dataSource" ref="dataSource"></property>
    	</bean>
    
    	
    	<bean id="dataSource"
    		class="org.springframework.jdbc.datasource.DriverManagerDataSource">
    		<property name="driverClassName" value="${jdbc.driverClass}"></property>
    		<property name="url" value="${jdbc.url}"></property>
    		<property name="username" value="${jdbc.username}"></property>
    		<property name="password" value="${jdbc.password}"></property>
    	</bean>
    
    </beans>

第二种方式:

spring 扫描引入资源配置文件(\*.properties)

<context:property-placeholder location="classpath:jdbc.properties"/>

演示实例:

<?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:property-placeholder location="classpath:jdbc.properties"/>
    
    	
    	<bean id="jdbcTemplate"
    		class="org.springframework.jdbc.core.JdbcTemplate">
    		<property name="dataSource" ref="dataSource"></property>
    	</bean>
    
    	
    	<bean id="dataSource"
    		class="org.springframework.jdbc.datasource.DriverManagerDataSource">
    		<property name="driverClassName" value="${jdbc.driverClass}"></property>
    		<property name="url" value="${jdbc.url}"></property>
    		<property name="username" value="${jdbc.username}"></property>
    		<property name="password" value="${jdbc.password}"></property>
    	</bean>
    
    </beans>

1.3 JdbcTemplate 增删改查

spring的配置文件(common.xml)

核心功能代码:

package com.zzg.jdbc.template;
    
    import java.sql.ResultSet;
    import java.sql.SQLException;
    import java.util.List;
    
    import org.springframework.context.ApplicationContext;
    import org.springframework.context.support.ClassPathXmlApplicationContext;
    import org.springframework.jdbc.core.JdbcTemplate;
    import org.springframework.jdbc.core.RowMapper;
    
    import com.alibaba.fastjson.JSONObject;
    
    public class Common {
    
    	public static void main(String[] args) {
    		// TODO Auto-generated method stub
    		// 1.获取 Spring 容器
    				ApplicationContext ac = new ClassPathXmlApplicationContext("common.xml");
    				// 2.根据 id 获取 bean 对象
    				JdbcTemplate jt = (JdbcTemplate) ac.getBean("jdbcTemplate");
    				
    				// 调用新增方法
    				// insert(jt, "大数据学习教程");
    				
    				// 调用修改方法
    				// update(jt,"黑马程序员-大数据学习教程", 7);
    				
    				// 调用删除方法
    				// delete(jt, 7);
    				// 调用查询方法
    				select(jt);
    	}
    	
    	public static void insert(JdbcTemplate jt, String name) {
    		jt.execute("insert into blog_tag(name) values ('" + name + "')");
    	}
    	
    	public static void update(JdbcTemplate jt, String name, Integer id) {
    		jt.update("update blog_tag set name = ? where id = ?", name, id);
    	}
    	
    	public static void select(JdbcTemplate jt) {
    		
    	List<JSONObject> list =	jt.query("select * from blog_tag", new RowMapper() {
    
    			@Override
    			public Object mapRow(ResultSet rs, int rowNum) throws SQLException {
    				// TODO Auto-generated method stub
    				JSONObject object = new JSONObject();
    				Integer id = rs.getInt(1);
    				String name = rs.getString(2);
    				
    				object.put("id", id);
    				object.put("name", name);
    				return object;
    			}
    			
    		});
    	
    		System.out.println(list.toString());
    	}
    	
    	public static void delete(JdbcTemplate jt, Integer id) {
    		jt.update("delete from blog_tag where id = ?", id);
    	}
    
    }