package com.jkurrent.framework.mybatis;
import com.jkurrent.framework.service.sqlmap.impl.SqlMapFactoryBean;
import org.apache.ibatis.builder.xml.XMLMapperBuilder;
import org.apache.ibatis.executor.ErrorContext;
import org.apache.ibatis.session.Configuration;
import org.springframework.beans.BeansException;
import org.springframework.beans.factory.DisposableBean;
import org.springframework.beans.factory.InitializingBean;
import org.springframework.context.ApplicationContext;
import org.springframework.context.ApplicationContextAware;
import org.springframework.context.ConfigurableApplicationContext;
import org.springframework.core.NestedIOException;
import org.springframework.core.io.Resource;
import org.springframework.core.io.support.PathMatchingResourcePatternResolver;
import org.springframework.core.io.support.ResourcePatternResolver;
import org.springframework.util.ClassUtils;
import org.springframework.util.StringUtils;
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;
/**
* 监听MyBatis的Mapper.xml的修改,自动刷新配置
*
* @author wuzhilang
* @version V1.00
*/
public class XMLMapperLoader implements DisposableBean, InitializingBean, ApplicationContextAware {
private ConfigurableApplicationContext context = null;
private transient String basePackage = null;
private HashMap<String, String> fileMapping = new HashMap<String, String>();
private Scanner scanner = null;
private ScheduledExecutorService service = null;
@Override
public void setApplicationContext(ApplicationContext applicationContext) throws BeansException {
this.context = (ConfigurableApplicationContext) applicationContext;
}
@Override
public void afterPropertiesSet() throws Exception {
try {
service = Executors.newScheduledThreadPool(1);
// 获取xml所在包
basePackage = "sqlmap";
// 触发文件监听事件
scanner = new Scanner();
scanner.scan();
service.scheduleAtFixedRate(new Task(), 5, 5, TimeUnit.SECONDS);
} catch (Exception e1) {
e1.printStackTrace();
}
}
class Task implements Runnable {
@Override
public void run() {
try {
if (scanner.isChanged()) {
// System.out.println("*_SqlMap.xml文件改变,重新加载.");
scanner.reloadXML();
System.out.println("加载完毕.");
}
} catch (Exception e) {
e.printStackTrace();
}
}
}
@SuppressWarnings({"rawtypes"})
class Scanner {
private String[] basePackages;
private static final String XML_RESOURCE_PATTERN = "**\\*_SqlMap.xml";
private ResourcePatternResolver resourcePatternResolver = new PathMatchingResourcePatternResolver();
public Scanner() {
basePackages = StringUtils.tokenizeToStringArray(XMLMapperLoader.this.basePackage,
ConfigurableApplicationContext.CONFIG_LOCATION_DELIMITERS);
}
public Resource[] getResource(String basePackage, String pattern) throws IOException {
String packageSearchPath = ResourcePatternResolver.CLASSPATH_ALL_URL_PREFIX
+ ClassUtils.convertClassNameToResourcePath(context.getEnvironment().resolveRequiredPlaceholders(
basePackage)) + "/" + pattern;
Resource[] resources = resourcePatternResolver.getResources(packageSearchPath);
return resources;
}
public void reloadXML() throws Exception {
Set<Map.Entry<String, SqlMapFactoryBean>> set = context.getBeansOfType(SqlMapFactoryBean.class).entrySet();
for(Map.Entry<String, SqlMapFactoryBean> entry : set) {
System.out.println("更新数据源:" + entry);
SqlMapFactoryBean factory = entry.getValue();
Configuration configuration = factory.getSqlSessionFactory().getConfiguration();
// 移除加载项
removeConfig(configuration);
// 重新扫描加载
for (String basePackage : basePackages) {
Resource[] resources = getResource(basePackage, XML_RESOURCE_PATTERN);
if (resources != null) {
for (int i = 0; i < resources.length; i++) {
if (resources[i] == null) {
continue;
}
try {
XMLMapperBuilder xmlMapperBuilder = new XMLMapperBuilder(resources[i].getInputStream(),
configuration, resources[i].toString(), configuration.getSqlFragments());
xmlMapperBuilder.parse();
} catch (Exception e) {
throw new NestedIOException("Failed to parse mapping resource: '" + resources[i] + "'", e);
} finally {
ErrorContext.instance().reset();
}
}
}
}
}
}
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");
}
private void clearMap(Class<?> classConfig, Configuration configuration, String fieldName) throws Exception {
Field field = classConfig.getDeclaredField(fieldName);
field.setAccessible(true);
Map mapConfig = (Map) field.get(configuration);
mapConfig.clear();
}
private void clearSet(Class<?> classConfig, Configuration configuration, String fieldName) throws Exception {
Field field = classConfig.getDeclaredField(fieldName);
field.setAccessible(true);
Set setConfig = (Set) field.get(configuration);
setConfig.clear();
}
public void scan() throws IOException {
if (!fileMapping.isEmpty()) {
return;
}
for (String basePackage : basePackages) {
Resource[] resources = getResource(basePackage, XML_RESOURCE_PATTERN);
if (resources != null) {
for (int i = 0; i < resources.length; i++) {
String multi_key = getValue(resources[i]);
fileMapping.put(resources[i].getFile().getPath(), multi_key);
}
}
}
}
private String getValue(Resource resource) throws IOException {
String contentLength = String.valueOf((resource.contentLength()));
String lastModified = String.valueOf((resource.lastModified()));
return new StringBuilder(contentLength).append(lastModified).toString();
}
public boolean isChanged() throws IOException {
boolean isChanged = false;
for (String basePackage : basePackages) {
Resource[] resources = getResource(basePackage, XML_RESOURCE_PATTERN);
if (resources != null) {
for (int i = 0; i < resources.length; i++) {
String name = resources[i].getFile().getPath();
String value = fileMapping.get(name);
String multi_key = getValue(resources[i]);
if (!multi_key.equals(value)) {
System.out.println(name + "文件改变, 准备重新加载");
isChanged = true;
fileMapping.put(name, multi_key);
}
}
}
}
return isChanged;
}
}
@Override
public void destroy() throws Exception {
if (service != null) {
service.shutdownNow();
}
}
public String getBasePackage() {
return basePackage;
}
public void setBasePackage(String basePackage) {
this.basePackage = basePackage;
}
}