剛剛接觸springboot，對很多東西都不熟悉，例如，它的註解方式，他的配置方式等；聽說它很牛逼，所以就嘗試著去學習。在基本熟悉springboot的第一個程序之後。想到當時spring整合mybatis時使用了數據源連接數據庫，所以自己也想嘗試使用c3p0連接數據庫。所以就有了以下的內容：
首先第一步，創建maven項目導入包：
pom.xml
<parent> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-parent</artifactId> <version>1.4.1.RELEASE</version> </parent> <dependencies> <dependency> <groupId>junit</groupId> <artifactId>junit</artifactId> <version>4.12</version> <scope>test</scope> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-test</artifactId> <version>1.4.1.RELEASE</version> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-web</artifactId> <version>1.4.1.RELEASE</version> </dependency> <dependency> <groupId>org.mybatis.spring.boot</groupId> <artifactId>mybatis-spring-boot-starter</artifactId> <version>1.1.1</version> </dependency> <dependency> <groupId>mysql</groupId> <artifactId>mysql-connector-java</artifactId> <version>5.1.33</version> </dependency> <dependency> <groupId>c3p0</groupId> <artifactId>c3p0</artifactId> <version>0.9.1.2</version> </dependency> </dependencies> <build> <plugins> <plugin> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-maven-plugin</artifactId> </plugin> </plugins> </build>
應用服務類
import org.mybatis.spring.annotation.MapperScan;import org.springframework.boot.SpringApplication;import org.springframework.boot.autoconfigure.EnableAutoConfiguration;import org.springframework.boot.autoconfigure.SpringBootApplication;@SpringBootApplication@MapperScan(value="com.myk.spring.t3")//掃描mapper包@EnableAutoConfiguration//自動載入應用程序所需的所有Bean，當使用Exclude這個屬性時，是禁止自動配置某個類public class Application { public static void main(String[] args) { SpringApplication.run(Application.class, args); }}配置文件內容（配置數據庫）
datasource: url: jdbc:mysql://ip:port/databaseName driver-class: com.mysql.jdbc.Driver username: *** password: ***
準備無誤，嘗試啟用應用服務，沒有報錯即可繼續配置數據源，嘗試很多方法，自己注入是不可能的，所以，我就想到spring的配置，嘗試按照那樣的方式去配置，所以，DataSourceConfig.java
import javax.sql.DataSource;import org.mybatis.spring.SqlSessionFactoryBean;import org.springframework.beans.factory.annotation.Qualifier;import org.springframework.boot.autoconfigure.jdbc.DataSourceBuilder;import org.springframework.boot.context.properties.ConfigurationProperties;import org.springframework.context.annotation.Bean;import org.springframework.context.annotation.Configuration;import org.springframework.context.annotation.Primary;import com.mchange.v2.c3p0.ComboPooledDataSource;@Configurationpublic class DataSourceConfig { @Bean(name="dataSource") @Qualifier(value="dataSource")//限定描述符除了能根據名字進行注入，但能進行更細粒度的控制如何選擇候選者@Primary//用@Primary區分主數據源@ConfigurationProperties(prefix="c3p0.primary")//指定配置文件中，前綴為c3p0的屬性值public DataSource dataSource(){ return DataSourceBuilder.create().type(ComboPooledDataSource.class).build();//創建數據源} /** *返回sqlSessionFactory */ @Bean public SqlSessionFactoryBean sqlSessionFactoryBean(){ SqlSessionFactoryBean sqlSessionFactory = new SqlSessionFactoryBean(); sqlSessionFactory.setDataSource(dataSource()); return sqlSessionFactory; }}也許會有疑問，為什麼這裡只需要一個sqlSessionFactory，這個具體要去熟悉spring整合mybatis。還有看看底層就明白了這樣就可以自動裝配了。
數據源都準備好了，嘗試連接數據庫吧
編輯接口
ExamPleMapper.java
import java.util.List;public interface ExamPleMapper { public List<Users> getUsers();}編輯Mapper xml文件
<?xml version="1.0" encoding="UTF-8"?><!DOCTYPE mapperPUBLIC "-//mybatis.org//DTD Mapper 3.0//EN""http://mybatis.org/dtd/mybatis-3-mapper.dtd"><mapper namespace="com.*.ExamPleMapper"> <select id="getUsers" resultType="com.*.Users"> select * from users </select></mapper>
編輯實體類，因為要將結果反射到bean類中
Users.java
public class Users { private int userid; private String username; @Override public String toString() { return "Users [userid=" + userid + ", username=" + username + "]"; } public int getUserid() { return userid; } public void setUserid(int userid) { this.userid = userid; } public String getUsername() { return username; } public void setUsername(String username) { this.username = username; } public Users(int userid, String username) { super(); this.userid = userid; this.username = username; } public Users() { super(); // TODO Auto-generated constructor stub }}編輯實現
Example2.java
import java.util.List;import org.springframework.beans.factory.annotation.Autowired;import org.springframework.web.bind.annotation.RequestMapping;import org.springframework.web.bind.annotation.ResponseBody;import org.springframework.web.bind.annotation.RestController;@RestController@RequestMapping(value="/example2")//映射public class Example2 { @Autowired public ExamPleMapper examPleMapper; @ResponseBody @RequestMapping(value="/gu") public List<Users> getUsers(){ return examPleMapper.getUsers(); }}輸入地址：http://localhost:8080/example2/gu
面顯示結果：
[{“userid”:1,”username”:”as”},{“userid”:2,”username”:”we”},{“userid”:3,”username”:”zx”}]
以上就是本文的全部內容，希望對大家的學習有所幫助，也希望大家多多支持武林網。