Spring Boot整合MyBatis學習總結

      公司的很多項目都陸陸續續引入了Spring Boot，通過對Spring Boot的接觸了解發現其真的是大大地簡化了開發、簡化了依賴配置，很多功能注解一下就可以實現，真的是太方便了。下面記錄了一個Spring Boot的入門程序實現，包括過濾器、servlet、定時器、全局異常處理、日志、Druid數據源的SQL監控配置。

1，pom.xml文件：

<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>4.0.0</modelVersion>

  <groupId>com.zws</groupId>
  <artifactId>spring-boot</artifactId>
  <version>0.0.1-SNAPSHOT</version>
  <packaging>jar</packaging>

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

  <properties>
    <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
  </properties>
  
  <parent>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-parent</artifactId>
    <version>1.5.10.RELEASE</version>
  </parent>

  <dependencies>
	<dependency>
	    <groupId>org.springframework.boot</groupId>
	    <artifactId>spring-boot-starter-web</artifactId>
	    <exclusions>
	        <exclusion>
	           <groupId>org.springframework.boot</groupId>
	           <artifactId>spring-boot-starter-logging</artifactId>
	        </exclusion>
		</exclusions>
	</dependency>
	
	<dependency>
	    <groupId>org.springframework.boot</groupId>
	    <artifactId>spring-boot-starter-aop</artifactId>
	</dependency>
	
	<dependency>
	    <groupId>org.springframework.boot</groupId>
	    <artifactId>spring-boot-starter-jdbc</artifactId>
	</dependency>
	
	<dependency>
	    <groupId>org.mybatis.spring.boot</groupId>
	    <artifactId>mybatis-spring-boot-starter</artifactId>
	    <version>1.3.1</version>
	</dependency>
	
	<dependency>
	    <groupId>com.alibaba</groupId>
	    <artifactId>druid-spring-boot-starter</artifactId>
	    <version>1.1.0</version>
	</dependency>
	
	<dependency>  
	    <groupId>mysql</groupId>  
	    <artifactId>mysql-connector-java</artifactId>  
	</dependency>
	
	<dependency>
	    <groupId>commons-logging</groupId>
	    <artifactId>commons-logging</artifactId>
	    <version>1.2</version>
	</dependency>
	
	<dependency>
	    <groupId>org.slf4j</groupId>
	    <artifactId>slf4j-api</artifactId>
	</dependency>
	
	<dependency>
	    <groupId>log4j</groupId>
	    <artifactId>log4j</artifactId>
	    <version>1.2.17</version>
	</dependency>
	
	<dependency>
	    <groupId>com.alibaba</groupId>
	    <artifactId>fastjson</artifactId>
	    <version>1.2.46</version>
	</dependency>
	
	<dependency>
	    <groupId>junit</groupId>
	    <artifactId>junit</artifactId>
	    <scope>test</scope>
	</dependency>
  </dependencies>
  
  <build>
      <plugins>
      	  <plugin>
		      <groupId>org.apache.maven.plugins</groupId>
			  <artifactId>maven-compiler-plugin</artifactId>
			  <configuration>
			      <source>1.8</source>
			      <target>1.8</target>
			  </configuration>
		  </plugin>
          <plugin>
              <groupId>org.springframework.boot</groupId>
              <artifactId>spring-boot-maven-plugin</artifactId>
          </plugin>
      </plugins>
  </build>
</project>

可以看到這個文件內容并不多，但是卻引入了很多需要的依賴。這里引入的Spring Boot版本為1.5.10.RELEASE，其中spring-boot-maven-plugin插件是Spring Boot提供的打包用的插件。mybatis-spring-boot-starter為MyBatis集成Spring Boot的依賴。druid-spring-boot-starter為阿里開源數據源Druid集成Spring Boot的依賴，它會下載對應的druid jar包，注意這里并沒有直接引入Druid依賴，如果直接引入Druid依賴jar包，則druid的監控頁面無法顯示sql。

2，Spring Boot配置文件resources/application.properties：

server.port=8080
server.context-path=/app
spring.mvc.throw-exception-if-no-handler-found=true
spring.resources.add-mappings=false

#tomcat訪問日志
server.tomcat.basedir=logs
server.tomcat.accesslog.enabled=true
server.tomcat.accesslog.directory=access
server.tomcat.accesslog.pattern=%t %a "%r" %s %b (%D ms)

datasource.druid.url=jdbc:mysql://localhost/db_boot?useUnicode=true&characterEncoding=utf8&autoReconnect=true&failOverReadOnly=false
datasource.druid.username=root
datasource.druid.password=root
datasource.druid.driver-class-name=com.mysql.jdbc.Driver
datasource.druid.initialSize=5
datasource.druid.minIdle=5
datasource.druid.maxActive=20
datasource.druid.maxWait=60000
datasource.druid.minEvictableIdleTimeMillis=300000
datasource.druid.validationQuery=select 'x'
datasource.druid.testOnBorrow=false
datasource.druid.testOnReturn=false
datasource.druid.testWhileIdle=true
datasource.druid.poolPreparedStatements=false
datasource.druid.maxPoolPreparedStatementPerConnectionSize=100
datasource.druid.filters=stat,wall,log4j

mybatis.config-location=classpath:mybatis/mybatis-config.xml
mybatis.mapper-locations=classpath:mybatis/mapper/*.xml

application.properties文件為Spring Boot的總配置文件，Spring Boot默認會加載resources目錄下的application.properties文件。Spring Boot默認內嵌Tomcat作為web容器，server.port為端口，server.context-path為上下文路徑。datasource開頭的為druid數據源的配置。

3，MyBatis的配置文件resources/mybatis/mybatis-config.xml:

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE configuration PUBLIC "-//mybatis.org//DTD Config 3.0//EN" "http://mybatis.org/dtd/mybatis-3-config.dtd">
<configuration>
	<settings>
		<setting name="cacheEnabled" value="true" />
		<setting name="lazyLoadingEnabled" value="true" />
		<setting name="multipleResultSetsEnabled" value="true" />
		<setting name="useColumnLabel" value="true" />
		<setting name="useGeneratedKeys" value="false" />
		<setting name="autoMappingBehavior" value="PARTIAL" />
		<setting name="autoMappingUnknownColumnBehavior" value="WARNING" />
		<setting name="defaultExecutorType" value="SIMPLE" />
		<setting name="defaultStatementTimeout" value="25" />
		<setting name="defaultFetchSize" value="100" />
		<setting name="safeRowBoundsEnabled" value="false" />
		<setting name="mapUnderscoreToCamelCase" value="false" />
		<setting name="localCacheScope" value="SESSION" />
		<setting name="jdbcTypeForNull" value="OTHER" />
		<setting name="lazyLoadTriggerMethods" value="equals,clone,hashCode,toString" />
	</settings>
	<typeAliases>
		<package name="com.zws.be.user.bean" />
	</typeAliases>
</configuration>

此配置文件的路徑已經配置在了resources/application.properties文件內。

4，resources/mybatis/UserMapper.xml:

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE mapper PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN" "http://mybatis.org/dtd/mybatis-3-mapper.dtd" >
<mapper namespace="com.zws.be.user.mapper.UserMapper" >
    <resultMap id="UserMap" type="User">
        <id column="id" property="id" jdbcType="BIGINT" />
        <result column="name" property="name" jdbcType="VARCHAR" />
        <result column="pass" property="pass" jdbcType="VARCHAR" />
        <result column="create_date" property="createDate" />
    </resultMap>
    <select id="getAll" resultMap="UserMap">
       select id, name, pass, create_date from user
    </select>
    
    <select id="getUserById" resultMap="UserMap" parameterType="long">
    	select id, name, pass, create_date from user where id = #{value}
    </select>
</mapper>

5，Sping Boot啟動類Application.java:

package com.zws.be;

import javax.sql.DataSource;

import org.mybatis.spring.annotation.MapperScan;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.boot.autoconfigure.jdbc.DataSourceBuilder;
import org.springframework.boot.context.properties.ConfigurationProperties;
import org.springframework.boot.web.servlet.ServletComponentScan;
import org.springframework.context.annotation.Bean;
import org.springframework.scheduling.annotation.EnableScheduling;

import com.alibaba.druid.pool.DruidDataSource;

@SpringBootApplication
@MapperScan(basePackages = {"com.zws.be.*.mapper"})
@ServletComponentScan
@EnableScheduling
public class Application {
	
	public static void main(String[] args) {
		SpringApplication.run(Application.class, args);
	}
	
	@Bean("dataSource")
	@ConfigurationProperties("datasource.druid")
	public DataSource getDruidDataSource() {
		return DataSourceBuilder.create().type(DruidDataSource.class).build();
	}
}

這個是程序啟動的入口，里面有mian函數，運行此類即可啟動Spring Boot。注解@MapperScan(basePackages = {"com.zws.be.*.mapper"})指定了映射mapper文件的接口所在的包。@EnableScheduling注解用于開啟Spring的定時組件，下面會有例子。@ServletComponentScan注解搭配@WebServlet和@WebFilter注解使得定義servlet和filter時非常方便。

6，下面是定義一個簡單的restful接口所需的各類：

com.zws.be.user.bean.User：

package com.zws.be.user.bean;

import java.util.Date;

import org.apache.ibatis.type.Alias;
@Alias("User")
public class User {

	private Long id;
	private String name;
	private String pass;
	private Date createDate;
	
	public Long getId() {
		return id;
	}
	public void setId(Long id) {
		this.id = id;
	}
	public String getName() {
		return name;
	}
	public void setName(String name) {
		this.name = name;
	}
	public String getPass() {
		return pass;
	}
	public void setPass(String pass) {
		this.pass = pass;
	}
	public Date getCreateDate() {
		return createDate;
	}
	public void setCreateDate(Date createDate) {
		this.createDate = createDate;
	}
	@Override
	public String toString() {
		return "User [id=" + id + ", name=" + name + ", pass=" + pass + ", createDate=" + createDate + "]";
	}
	
}

com.zws.be.user.mapper.UserMapper：

package com.zws.be.user.mapper;

import java.util.List;

import com.zws.be.user.bean.User;

public interface UserMapper {

	List<User> getAll();
	
	User getUserById(Long id);
}

com.zws.be.user.service.UserService：

package com.zws.be.user.service;

import java.util.List;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;

import com.zws.be.user.bean.User;
import com.zws.be.user.mapper.UserMapper;

@Service
public class UserService {

	@Autowired
	private UserMapper userMapper;
	
	public List<User> getUsers() {
		return userMapper.getAll();
	}
	
	public User getUser(Long id) {
		return userMapper.getUserById(id);
	}
}

com.zws.be.user.controller.UserController：

package com.zws.be.user.controller;

import org.apache.log4j.Logger;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.RestController;

import com.alibaba.fastjson.JSON;
import com.alibaba.fastjson.serializer.SerializerFeature;
import com.zws.be.user.bean.User;
import com.zws.be.user.service.UserService;

@RestController
@RequestMapping("/user")
public class UserController {
	public Logger logger = Logger.getLogger(UserController.class);
	
	@Autowired
	private UserService userService;

	@RequestMapping(value="/{id}", method=RequestMethod.GET, produces = "application/json")
	public String hello(@PathVariable Long id) {
		User user = userService.getUser(id);
		return JSON.toJSONString(user, SerializerFeature.WriteDateUseDateFormat);
	}
}

7，配置Druid的sql監控servlet：

package com.zws.be.filter;

import javax.servlet.annotation.WebServlet;

import com.alibaba.druid.support.http.StatViewServlet;

/**
 * DRUID的sql監控
 * @author wensh.zhu
 * @2018-03-11
 */
@WebServlet(name="monitorSrvlet", urlPatterns= {"/druid/*"})
public class MonitorServlet extends StatViewServlet {
	
	private static final long serialVersionUID = -2211104135110049275L;

}

啟動后訪問http://localhost:8080/app/druid即可進入Druid的sql監控的監控頁面。

8，過濾器例子：

package com.zws.be.filter;

import java.io.IOException;

import javax.servlet.Filter;
import javax.servlet.FilterChain;
import javax.servlet.FilterConfig;
import javax.servlet.ServletException;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;
import javax.servlet.annotation.WebFilter;

import org.apache.log4j.Logger;

@WebFilter(filterName="filterDemo", urlPatterns = {"/*"})
public class FilterDemo implements Filter{
	private Logger logger = Logger.getLogger(FilterDemo.class);

	@Override
	public void destroy() {}

	@Override
	public void doFilter(ServletRequest arg0, ServletResponse arg1, FilterChain chain)
			throws IOException, ServletException {
		logger.info("FilterDemo is working...");
		chain.doFilter(arg0, arg1);
	}

	@Override
	public void init(FilterConfig arg0) throws ServletException {
		
		
	}

}

9，定時器例子：

package com.zws.be.timer;

import org.apache.log4j.Logger;
import org.springframework.scheduling.annotation.Scheduled;
import org.springframework.stereotype.Component;

@Component
public class TimerDemo {
	private Logger logger = Logger.getLogger(getClass());

	@Scheduled(cron = "0/30 * * * * *")  
	public void timer() {
		logger.info("定時器例子");
	}
}

10，全局異常處理：

package com.zws.be.exception;

import org.apache.log4j.Logger;
import org.springframework.web.bind.annotation.ExceptionHandler;
import org.springframework.web.bind.annotation.ResponseBody;
import org.springframework.web.bind.annotation.RestControllerAdvice;
/**
 * 全局異常處理
 * @author wensh.zhu
 * @2018-03-11
 */
@RestControllerAdvice
public class ExceptionAdvice {
	private Logger logger = Logger.getLogger(getClass());
	private String pattern = "抱歉，異常了：{0}";

	@ExceptionHandler(value = {Exception.class})
	@ResponseBody
	public String handleAllException(Exception e, HttpServletRequest req, HttpServletResponse resp) {
		logger.error("接口調用異常", e);
		if (e instanceof NoHandlerFoundException) {
			String reqURI = req.getRequestURI().toString();
			return MessageFormat.format(pattern, "資源" + reqURI + "不存在！！！");
		}
		return MessageFormat.format(pattern, e.getMessage());
	}
}

11，log4j配置文件resources/log4j.properties：

log4j.rootLogger=INFO, stdout, infoLog, errorLog

log4j.appender.stdout = org.apache.log4j.ConsoleAppender
log4j.appender.stdout.layout = org.apache.log4j.PatternLayout
log4j.appender.stdout.layout.conversionPattern = %d{yyyy-MM-dd HH\:mm\:ss}|%p|%C|%M|%L|%m%n

log4j.appender.infoLog=com.zws.be.log.MyRollingFileAppender
log4j.appender.infoLog.File=logs/info/info.log
log4j.appender.infoLog.Threshold = info
log4j.appender.infoLog.layout=org.apache.log4j.PatternLayout
log4j.appender.infoLog.layout.ConversionPattern=%d{yyyy-MM-dd HH\:mm\:ss}|%p|%C|%M|%L|%m%n

log4j.appender.errorLog=com.zws.be.log.MyRollingFileAppender
log4j.appender.errorLog.File=logs/error/error.log
log4j.appender.errorLog.Threshold = error
log4j.appender.errorLog.layout=org.apache.log4j.PatternLayout
log4j.appender.errorLog.layout.ConversionPattern=%d{yyyy-MM-dd HH\:mm\:ss}|%p|%C|%M|%L|%m%n

自定義日志生成文件名稱：

package com.zws.be.log;

import java.io.File;
import java.io.IOException;
import java.io.InterruptedIOException;

import org.apache.log4j.Priority;
import org.apache.log4j.RollingFileAppender;
import org.apache.log4j.helpers.CountingQuietWriter;
import org.apache.log4j.spi.LoggingEvent;

public class MyRollingFileAppender extends RollingFileAppender{

	private long nextRollover = 0L;
	
	public void rollOver() {
		File target, file;
		
		if (qw != null) {
			long size = ((CountingQuietWriter) qw).getCount();
			nextRollover = size + maxFileSize;
		}
		
		boolean renameSuccessed = true;
		if (maxBackupIndex > 0) {
			file = new File(getRollingFileName(fileName, maxBackupIndex));
			if (file.exists()) {
				renameSuccessed = file.delete();
			}
			
			for (int i = maxBackupIndex - 1; i >= 1 && renameSuccessed; i --) {
				file = new File(getRollingFileName(fileName, i));
				if (file.exists()) {
					target = new File(getRollingFileName(fileName, i + 1));
					renameSuccessed = file.renameTo(target);
				}
			}
			
			if (renameSuccessed) {
				target = new File(getRollingFileName(fileName, 1));
				closeFile();
				renameSuccessed = file.renameTo(target);
				
				if (!renameSuccessed) {
					try {
						setFile(fileName, true, bufferedIO, bufferSize);
					} catch (IOException e) {
						if (e instanceof InterruptedIOException) {
							Thread.currentThread().interrupt();
						}
					}
				}
			}
		}
	}
	
	private String getRollingFileName(String fileName, int index) {
		String fName = "";
		String newIndex = index < 10 ? ("0" + index) : String.valueOf(index);
		if (index > 0) {
			fName = fileName.replace(".log", "") + "_" + newIndex + ".log";
		} else {
			fName = fileName;
		}
		return fName;
	}
	
	@Override
	protected void subAppend(LoggingEvent event) {
		super.subAppend(event);
		if (fileName != null && qw != null) {
			long size = ((CountingQuietWriter) qw).getCount();
			if (size >= maxFileSize && size >= nextRollover) {
				rollOver();
			}
		}
	}
	
	@Override
	public boolean isAsSevereAsThreshold(Priority priority) {
		String level = priority.toString();
		if ("ERROR".equals(level)) {
			return getThreshold().equals(priority);
		}
		
		return super.isAsSevereAsThreshold(priority);
	}
}

12，Spring MVC請求參數以及返回信息自動日志的輔助類：

package com.zws.be.log;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.text.MessageFormat;

import org.apache.log4j.Logger;
import org.springframework.core.MethodParameter;
import org.springframework.http.MediaType;
import org.springframework.http.converter.HttpMessageConverter;
import org.springframework.http.server.ServerHttpRequest;
import org.springframework.http.server.ServerHttpResponse;
import org.springframework.web.bind.annotation.ControllerAdvice;
import org.springframework.web.servlet.mvc.method.annotation.ResponseBodyAdvice;
/**
 * 用于請求參數、響應信息的自動日志。
 * @author wensh.zhu
 * @2018-03-11
 */
@ControllerAdvice(basePackages = {"com.zws.be"})
public class LogResponseBodyAdvice implements ResponseBodyAdvice<String>{
	
	private String pattern = "\n---BEGIN---\nReqURI:{0}\nParams:{1}\nMethod:{2}\nReturn:{3}\n---END---";
	
	private Logger logger = Logger.getLogger(LogResponseBodyAdvice.class);

	@Override
	public String beforeBodyWrite(String rtnMsg, MethodParameter param, MediaType arg2,
			Class<? extends HttpMessageConverter<?>> arg3, ServerHttpRequest req, ServerHttpResponse resp) {
		String clazName = param.getDeclaringClass().getName();
		String mtdName = param.getMethod().getName();
		String reqURI = req.getURI().toString();
		String reqParams = getReqParams(req);

		String log = getLog(reqURI, reqParams, clazName + "." + mtdName, rtnMsg);
		logger.info(log);
		return rtnMsg;
	}

	@Override
	public boolean supports(MethodParameter arg0, Class<? extends HttpMessageConverter<?>> arg1) {
		return true;
	}
	
	private String getLog(String reqURI, String reqParams, String proMethod, String rtnMsg) {
		return MessageFormat.format(pattern, reqURI, reqParams, proMethod, rtnMsg);
	}

	private String getReqParams(ServerHttpRequest req) {
		StringBuilder body = new StringBuilder();
		String line = null;
		BufferedReader reader = null;
		try {
			reader = new BufferedReader(new InputStreamReader(req.getBody(), "UTF-8"));
			while ((line = reader.readLine()) != null) {
				body.append(line);
			}
		} catch (IOException e) {
			logger.error("I/O error ", e);
		} finally {
			try {
				if (reader != null) {
					reader.close();
				}
			} catch (IOException e) {
				logger.error("I/O error ", e);
			}
		}
		
		return body.toString();
	}
}

此類功能為將Spring MVC接受到請求的參數、處理請求對應的方法、請求返回內容自動打印到日志文件內，在接口出現問題的時候方便排查，日志輸出樣例：

---BEGIN---
ReqURI:http://localhost:8080/app/user/1
Params:
Method:com.zws.be.user.controller.UserController.hello
Return:{"createDate":"2018-03-04 15:44:25","id":1,"name":"zhangsan","pass":"zhangsan@123"}
---END---

13，運行Application，訪問http://localhost:8080/app/user/1，如下圖：

查看druid的監控：

項目目錄結構圖：