spring-boot使用教程(一)：让程序跑起来

简介

spring-boot是由Pivotal团队提供的全新框架，其设计目的是用来简化新Spring应用的初始搭建以及开发过程。该框架使用了特定的方式来进行配置，从而使开发人员不再需要定义样板化的配置。通过这种方式，Boot致力于在蓬勃发展的快速应用开发领域（rapid application development）成为领导者。

参考项目：https://github.com/bigbeef/cppba-spring-boot
开源地址：https://github.com/bigbeef
个人博客：http://blog.cppba.com

文件结构

maven的pom.xml配置

<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/maven-v4_0_0.xsd">
    <modelVersion>4.0.0</modelVersion>

    <groupId>com.cppbba</groupId>
    <artifactId>cppba-spring-boot</artifactId>
    <packaging>war</packaging>
    <version>1.0.0</version>

    <name>cppba-spring-boot Maven Webapp</name>
    <url>http://maven.apache.org</url>

    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>1.3.6.RELEASE</version>
    </parent>

    <properties>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
        <jdk.version>1.7</jdk.version>
        <spring.version>4.3.0.RELEASE</spring.version>
        <hibernate.version>4.3.11.Final</hibernate.version>
    </properties>

    <dependencies>
        <!--spring-->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-jdbc</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-orm</artifactId>
        </dependency>
        <!--mysql-->
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
        </dependency>
        <!-- hibernate-->
        <dependency>
            <groupId>org.hibernate</groupId>
            <artifactId>hibernate-entitymanager</artifactId>
            <version>${hibernate.version}</version>
        </dependency>
        <!--druid-->
        <dependency>
            <groupId>com.alibaba</groupId>
            <artifactId>druid</artifactId>
            <version>1.0.20</version>
        </dependency>
    </dependencies>

    <build>
        <finalName>cppba-spring-boot</finalName>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
            </plugin>
        </plugins>
    </build>
</project>

创建Application.java

package com.cppba;

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.core.env.Environment;

import java.net.UnknownHostException;

// same as @Configuration @EnableAutoConfiguration @ComponentScan
@SpringBootApplication
public class Application {
    public static void main(String[] args) throws UnknownHostException {
        SpringApplication app = new SpringApplication(Application.class);
        Environment environment = app.run(args).getEnvironment();
    }
}

创建DatabaseConfiguration.java

package com.cppba.config;

import com.alibaba.druid.pool.DruidDataSource;
import org.springframework.boot.bind.RelaxedPropertyResolver;
import org.springframework.context.ApplicationContextException;
import org.springframework.context.EnvironmentAware;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.core.env.Environment;
import org.springframework.orm.hibernate4.HibernateTransactionManager;
import org.springframework.orm.hibernate4.LocalSessionFactoryBean;
import org.springframework.transaction.annotation.EnableTransactionManagement;
import org.springframework.util.StringUtils;

import javax.sql.DataSource;
import java.sql.SQLException;
import java.util.Arrays;
import java.util.Properties;

@Configuration
@EnableTransactionManagement
public class DatabaseConfiguration implements EnvironmentAware {

    private Environment environment;
    private RelaxedPropertyResolver datasourcePropertyResolver;

    //从application.yml中读取资源
    @Override
    public void setEnvironment(Environment environment) {
        this.environment = environment;
        this.datasourcePropertyResolver = new RelaxedPropertyResolver(environment,
                "spring.datasource.");
    }

    //datasource
    @Bean(initMethod = "init", destroyMethod = "close")
    public DataSource dataSource() throws SQLException {
        if (StringUtils.isEmpty(datasourcePropertyResolver.getProperty("url"))) {
            System.out.println("Your database connection pool configuration is incorrect!" +
                    " Please check your Spring profile, current profiles are:"+
            Arrays.toString(environment.getActiveProfiles()));
            throw new ApplicationContextException(
                    "Database connection pool is not configured correctly");
        }
        DruidDataSource druidDataSource = new DruidDataSource();
        druidDataSource.setUrl(datasourcePropertyResolver.getProperty("url"));
        druidDataSource.setUsername(datasourcePropertyResolver
                .getProperty("username"));
        druidDataSource.setPassword(datasourcePropertyResolver
                .getProperty("password"));
        druidDataSource.setInitialSize(1);
        druidDataSource.setMinIdle(1);
        druidDataSource.setMaxActive(20);
        druidDataSource.setMaxWait(60000);
        druidDataSource.setTimeBetweenEvictionRunsMillis(60000);
        druidDataSource.setMinEvictableIdleTimeMillis(300000);
        druidDataSource.setValidationQuery("SELECT　'x'");
        druidDataSource.setTestWhileIdle(true);
        druidDataSource.setTestOnBorrow(false);
        druidDataSource.setTestOnReturn(false);
        return druidDataSource;
    }

    //sessionFactory
    @Bean
    public LocalSessionFactoryBean sessionFactory() throws SQLException{
        LocalSessionFactoryBean localSessionFactoryBean = new LocalSessionFactoryBean();
        localSessionFactoryBean.setDataSource(this.dataSource());
        Properties properties1 = new Properties();
        properties1.setProperty("hibernate.dialect","org.hibernate.dialect.MySQL5Dialect");
        properties1.setProperty("hibernate.show_sql","false");
        localSessionFactoryBean.setHibernateProperties(properties1);
        localSessionFactoryBean.setPackagesToScan("*");
        return localSessionFactoryBean;
    }

    //txManager事务开启
    @Bean
    public HibernateTransactionManager txManager() throws SQLException {
        HibernateTransactionManager hibernateTransactionManager = new HibernateTransactionManager();
        hibernateTransactionManager.setSessionFactory(sessionFactory().getObject());
        return hibernateTransactionManager;
    }
}

创建CommonAction.java(这是一个测试类)

package com.cppba.web;

import org.hibernate.SQLQuery;
import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.springframework.transaction.annotation.Transactional;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;

import javax.annotation.Resource;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
import java.util.List;

@RestController
@Transactional
public class CommonAction {

    @Resource
    private SessionFactory sessionFactory;

    @RequestMapping("test")
    public void test(HttpServletResponse response){
        Session session = sessionFactory.getCurrentSession();
        SQLQuery sqlQuery = session.createSQLQuery("select * from user");
        List list = sqlQuery.list();
        System.out.printf(list.size()+"");
        try {
            response.setContentType("application/json");
            response.setHeader("Cache-Control", "no-cache");
            response.setCharacterEncoding("UTF-8");
            response.getWriter().write("{\"msg\":\"调用成功\"}");
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}

创建application.yml

server:
    port: 8080
    address: localhost

spring:
    datasource:
        url: jdbc:mysql://localhost:3306/cppba
        username: root
        password: root

启动项目

我们点击启动按钮

控制台会打印如下内容：

启动成功
接下来我们访问http://127.0.0.1:8080/test
(我的CommonAction中RequestMapping(“test”),所以访问路径是test)

到此spring-boot配置成功！