[SPRING] MyBatis mapper.xml 수정시 서버 재시작없이 반영하기

MyBais를 사용할때 mapper.xml에서 쿼리를 바꾸고 적용시키려면 서버를 재시작 시켜야하는 부분이 번거롭다.

서버를 재시작하지않고 수정된 쿼리를 적용시키는 방법을 알아보자!

 

- RefreshableSqlSessionFactoryBean.java

import java.io.IOException;
import java.lang.reflect.InvocationHandler;
import java.lang.reflect.Method;
import java.lang.reflect.Proxy;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.Timer;
import java.util.TimerTask;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.ibatis.session.SqlSessionFactory;
import org.mybatis.spring.SqlSessionFactoryBean;
import org.springframework.beans.factory.DisposableBean;
import org.springframework.core.io.Resource;
import java.util.concurrent.locks.Lock;
import java.util.concurrent.locks.ReentrantReadWriteLock;

/**
 * mybatis mapper 자동 감지 후 자동으로 서버 재시작이 필요 없이 반영
 *
 * @author sbcoba
 */
public class RefreshableSqlSessionFactoryBean extends SqlSessionFactoryBean implements DisposableBean {
	private static final Log log = LogFactory.getLog(RefreshableSqlSessionFactoryBean.class);
	private SqlSessionFactory proxy;
	private int interval = 500;
	private Timer timer;
	private TimerTask task;
	private Resource[] mapperLocations;
	/**
	 * 파일 감시 쓰레드가 실행중인지 여부.
	 */
	private boolean running = false;
	private final ReentrantReadWriteLock rwl = new ReentrantReadWriteLock();
	private final Lock r = rwl.readLock();
	private final Lock w = rwl.writeLock();

	public void setMapperLocations(Resource[] mapperLocations) {
		super.setMapperLocations(mapperLocations);
		this.mapperLocations = mapperLocations;
	}

	public void setInterval(int interval) {
		this.interval = interval;
	}

	/**
	 * @throws Exception
	 */
	public void refresh() throws Exception {
		if (log.isInfoEnabled()) {
			log.info("refreshing sqlMapClient.");
		}
		w.lock();
		try {
			super.afterPropertiesSet();
		} finally {
			w.unlock();
		}
	}

	/**
	 * 싱글톤 멤버로 SqlMapClient 원본 대신 프록시로 설정하도록 오버라이드.
	 */
	public void afterPropertiesSet() throws Exception {
		super.afterPropertiesSet();
		setRefreshable();
	}

	private void setRefreshable() {
		proxy = (SqlSessionFactory) Proxy.newProxyInstance(SqlSessionFactory.class.getClassLoader(),
				new Class[] { SqlSessionFactory.class }, new InvocationHandler() {
					public Object invoke(Object proxy, Method method, Object[] args) throws Throwable {
						// log.debug("method.getName() : " + method.getName());
						return method.invoke(getParentObject(), args);
					}
				});
		task = new TimerTask() {
			private Map<Resource, Long> map = new HashMap<Resource, Long>();

			public void run() {
				if (isModified()) {
					try {
						refresh();
					} catch (Exception e) {
						log.error("caught exception", e);
					}
				}
			}

			private boolean isModified() {
				boolean retVal = false;
				if (mapperLocations != null) {
					for (int i = 0; i < mapperLocations.length; i++) {
						Resource mappingLocation = mapperLocations[i];
						retVal |= findModifiedResource(mappingLocation);
					}
				}
				return retVal;
			}

			private boolean findModifiedResource(Resource resource) {
				boolean retVal = false;
				List<String> modifiedResources = new ArrayList<String>();
				try {
					long modified = resource.lastModified();
					if (map.containsKey(resource)) {
						long lastModified = ((Long) map.get(resource)).longValue();
						if (lastModified != modified) {
							map.put(resource, new Long(modified));
							modifiedResources.add(resource.getDescription());
							retVal = true;
						}
					} else {
						map.put(resource, new Long(modified));
					}
				} catch (IOException e) {
					log.error("caught exception", e);
				}
				if (retVal) {
					if (log.isInfoEnabled()) {
						log.info("modified files : " + modifiedResources);
					}
				}
				return retVal;
			}
		};
		timer = new Timer(true);
		resetInterval();
	}

	private Object getParentObject() throws Exception {
		r.lock();
		try {
			return super.getObject();
		} finally {
			r.unlock();
		}
	}

	public SqlSessionFactory getObject() {
		return this.proxy;
	}

	public Class<? extends SqlSessionFactory> getObjectType() {
		return (this.proxy != null ? this.proxy.getClass() : SqlSessionFactory.class);
	}

	public boolean isSingleton() {
		return true;
	}

	public void setCheckInterval(int ms) {
		interval = ms;
		if (timer != null) {
			resetInterval();
		}
	}

	private void resetInterval() {
		if (running) {
			timer.cancel();
			running = false;
		}
		if (interval > 0) {
			timer.schedule(task, 0, interval);
			running = true;
		}
	}

	public void destroy() throws Exception {
		timer.cancel();
	}
}

 

- context-mapper.xml 설정

1. bean의 class는 위의 RefreshableSqlSessionFactoryBean.java 의 경로

2. property mapperLocations의 value는 재로딩 될 xml 파일 경로

<!-- SqlSession setup for MyBatis Database Layer -->
<bean id="sqlSession" class="패키지경로.RefreshableSqlSessionFactoryBean">
	<property name="dataSource" ref="dataSource" />
	<property name="configLocation" value="classpath:/MapperConfig.xml" />
	<property name="mapperLocations" value="classpath:/패키지경로/**/maper.xml" />
</bean>