自动刷新xml

@RestController
@SpringBootApplication
public class RenrenApplication {
    @Autowired
    XMLMapperLoader xmlMapperLoader;
public static void main(String[] args) {
    SpringApplication.run(RenrenApplication.class, args);
}


/**
 * 第一种方式，通过Spring的方式创建Bean来管理，在构造方法中会启动新的线程
 *
 * @return
 */
@Bean
public XMLMapperLoader xmlMapperLoader(SqlSessionFactory sqlSessionFactory) {
    return new XMLMapperLoader(sqlSessionFactory, "classpath:mapper/**/*.xml");
}

/**
 * 第二种方式 通过URL来刷新
 *
 * @return
 */
@RequestMapping("refresh")
public String refreshMyBatisXml() {
    return xmlMapperLoader.readMapperXml();
}

}

package io.renren.common.utils;
import java.io.IOException;

import java.lang.reflect.Field;

import java.util.HashMap;

import java.util.Map;

import java.util.Set;

import java.util.concurrent.Executors;

import java.util.concurrent.ScheduledExecutorService;

import java.util.concurrent.TimeUnit;
import org.apache.ibatis.builder.xml.XMLMapperBuilder;

import org.apache.ibatis.session.Configuration;

import org.apache.ibatis.session.SqlSessionFactory;

import org.slf4j.Logger;

import org.slf4j.LoggerFactory;

import org.springframework.core.io.Resource;

import org.springframework.core.io.support.PathMatchingResourcePatternResolver;
/**


@author yuxuan

*/

public class XMLMapperLoader {
private Logger logger = LoggerFactory.getLogger(XMLMapperLoader.class);

private SqlSessionFactory sqlSessionFactory;

private Resource[] mapperLocations;

private String packageSearchPath = "classpath:mapper/**/*.xml";

private HashMap<String, Long> fileMapping = new HashMap<String, Long>();
public XMLMapperLoader(SqlSessionFactory sqlSessionFactory, String packageSearchPath) {

this.sqlSessionFactory = sqlSessionFactory;

if (packageSearchPath != null && packageSearchPath != "") 

//        startThreadListener();

}
public void startThreadListener() {

ScheduledExecutorService service = Executors.newScheduledThreadPool(1);

//每5秒执行一次

service.scheduleAtFixedRate(new Runnable() {

@Override

public void run() {

readMapperXml();

}

}, 0, 5, TimeUnit.SECONDS);

}
public String readMapperXml() {

try {

org.apache.ibatis.session.Configuration configuration = sqlSessionFactory.getConfiguration();

// step.1 扫描文件

try {

this.scanMapperXml();

} catch (IOException e) {

return "packageSearchPath扫描包路径配置错误";

}
     for (String name : configuration.getMappedStatementNames()) {
         logger.debug(name);
     }

     // step.2 判断是否有文件发生了变化
     if (this.isChanged()) {
         // step.2.1 清理
         this.removeConfig(configuration);
         // step.2.2 重新加载
         for (Resource configLocation : mapperLocations) {
             try {
                 XMLMapperBuilder xmlMapperBuilder = new XMLMapperBuilder(configLocation.getInputStream(), configuration, configLocation.toString(), configuration.getSqlFragments());
                 xmlMapperBuilder.parse();
                 logger.debug(&quot;mapper文件[&quot; + configLocation.getFilename() + &quot;]缓存加载成功&quot;);
             } catch (IOException e) {
                 logger.debug(&quot;mapper文件[&quot; + configLocation.getFilename() + &quot;]不存在或内容格式不对&quot;);
                 continue;
             }
         }
     }

     for (String name : configuration.getMappedStatementNames()) {
         logger.debug(name);
     }
     return &quot;刷新mybatis xml配置语句成功&quot;;
 } catch (Exception e) {
     e.printStackTrace();
     return &quot;刷新mybatis xml配置语句失败&quot;;
 }

}
public void setPackageSearchPath(String packageSearchPath)
public void setSqlSessionFactory(SqlSessionFactory sqlSessionFactory)
/**

扫描xml文件所在的路径

@throws IOException

*/

private void scanMapperXml() throws IOException {

this.mapperLocations = new PathMatchingResourcePatternResolver().getResources(packageSearchPath);

}

/**


清空Configuration中几个重要的缓存



@param configuration


@throws Exception

*/

private void removeConfig(Configuration configuration) throws Exception {

Class<?> classConfig = configuration.getClass();

clearMap(classConfig, configuration, "mappedStatements");

clearMap(classConfig, configuration, "caches");

clearMap(classConfig, configuration, "resultMaps");

clearMap(classConfig, configuration, "parameterMaps");

clearMap(classConfig, configuration, "keyGenerators");

clearMap(classConfig, configuration, "sqlFragments");
clearSet(classConfig, configuration, "loadedResources");


}
@SuppressWarnings("rawtypes")

private void clearMap(Class<?> classConfig, Configuration configuration, String fieldName) throws Exception {

Field field = null;

if (configuration.getClass().getName().equals("com.baomidou.mybatisplus.core.MybatisConfiguration"))  else 

field.setAccessible(true);

Map mapConfig = (Map) field.get(configuration);

mapConfig.clear();

}
@SuppressWarnings("rawtypes")

private void clearSet(Class<?> classConfig, Configuration configuration, String fieldName) throws Exception {

Field field = null;

if (configuration.getClass().getName().equals("com.baomidou.mybatisplus.core.MybatisConfiguration"))  else 

field.setAccessible(true);

Set setConfig = (Set) field.get(configuration);

setConfig.clear();

}
/**


判断文件是否发生了变化



@param resource


@return


@throws IOException

*/

private boolean isChanged() throws IOException {

boolean flag = false;

for (Resource resource : mapperLocations) {

String resourceName = resource.getFilename();
 boolean addFlag = !fileMapping.containsKey(resourceName);// 此为新增标识

 // 修改文件:判断文件内容是否有变化
 Long compareFrame = fileMapping.get(resourceName);
 long lastFrame = resource.contentLength() + resource.lastModified();
 boolean modifyFlag = null != compareFrame && compareFrame.longValue() != lastFrame;// 此为修改标识

 // 新增或是修改时,存储文件
 if (addFlag || modifyFlag) {
     fileMapping.put(resourceName, Long.valueOf(lastFrame));// 文件内容帧值
     flag = true;
 }

}

return flag;

}




}