package com.st.tks.utils.mybatis;

import com.google.common.collect.Sets;
import org.apache.commons.lang3.StringUtils;
import org.apache.ibatis.builder.xml.XMLMapperBuilder;
import org.apache.ibatis.executor.ErrorContext;
import org.apache.ibatis.session.Configuration;
import org.apache.ibatis.session.SqlSessionFactory;
import org.slf4j.LoggerFactory;
import org.springframework.beans.BeansException;
import org.springframework.context.ApplicationContext;
import org.springframework.context.ApplicationContextAware;
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.stereotype.Component;
import org.springframework.util.ClassUtils;

import javax.annotation.PostConstruct;
import java.io.;
import java.lang.reflect.Field;
import java.util.;

@Component
public class MapperRefresh implements ApplicationContextAware {

private static org.slf4j.Logger log = LoggerFactory.getLogger(MapperRefresh.class.getName());private static String filename = "/conf/mybatis-refresh.properties";private static Properties prop = new Properties();private ApplicationContext applicationContext ;private static boolean enabled; // 是否启用Mapper刷新线程功能private static boolean refresh; // 刷新启用后，是否启动了刷新线程private Set<String> location; // Mapper实际资源路径private Resource[] mapperLocations; // Mapper资源路径private Configuration configuration; // MyBatis配置对象private Long beforeTime = 0L; // 上一次刷新时间private static int delaySeconds; // 延迟刷新秒数private static int sleepSeconds; // 休眠时间private static String mappingPath; // xml文件夹匹配字符串，需要根据需要修改private static final String XML_RESOURCE_PATTERN = "**/*.xml";private String basePackage = "/mybatis";static { try { prop.load(MapperRefresh.class.getResourceAsStream(filename)); } catch (Exception e) { log.error("Load mybatis-refresh “"+filename+"” file error."); } enabled = "true".equalsIgnoreCase(getPropString("enabled")); delaySeconds = getPropInt("delaySeconds"); sleepSeconds = getPropInt("sleepSeconds"); mappingPath = getPropString("mappingPath"); delaySeconds = delaySeconds == 0 ? 50 : delaySeconds; sleepSeconds = sleepSeconds == 0 ? 3 : sleepSeconds; mappingPath = StringUtils.isBlank(mappingPath) ? "mappings" : mappingPath; log.debug("[enabled] " + enabled); log.debug("[delaySeconds] " + delaySeconds); log.debug("[sleepSeconds] " + sleepSeconds); log.debug("[mappingPath] " + mappingPath);}@PostConstructpublic void start() throws IOException { SqlSessionFactory factory = applicationContext.getBean(SqlSessionFactory.class); Configuration configuration = factory.getConfiguration(); this.configuration = configuration ; mapperLocations = getResource(basePackage, XML_RESOURCE_PATTERN); exeTask();}public static boolean isRefresh() { return refresh;}public void exeTask() { beforeTime = System.currentTimeMillis(); log.debug("[location] " + location); log.debug("[configuration] " + configuration); if (enabled) { // 启动刷新线程 final MapperRefresh runnable = this; new Thread(new Runnable() { @Override public void run() { if (location == null){ location = Sets.newHashSet(); log.debug("MapperLocation's length:" + mapperLocations.length); for (Resource mapperLocation : mapperLocations) { String s = mapperLocation.toString().replaceAll("\\\\", "/"); s = s.substring("file [".length(), s.lastIndexOf(mappingPath) + mappingPath.length()); if (!location.contains(s)) { location.add(s); log.debug("Location:" + s); } } log.debug("Locarion's size:" + location.size()); } try { Thread.sleep(delaySeconds * 1000); } catch (InterruptedException e2) { e2.printStackTrace(); } refresh = true; log.info("========= Enabled refresh mybatis mapper ========="); while (true) { try { for (String s : location) { runnable.refresh(s, beforeTime); } } catch (Exception e1) { e1.printStackTrace(); } try { Thread.sleep(sleepSeconds * 1000); } catch (InterruptedException e) { e.printStackTrace(); } } } }, "MyBatis-Mapper-Refresh").start(); }}/** * 执行刷新 * @param filePath 刷新目录 * @param beforeTime 上次刷新时间 * @throws NestedIOException 解析异常 * @throws FileNotFoundException 文件未找到 * @author ThinkGem */@SuppressWarnings({ "rawtypes", "unchecked" })private void refresh(String filePath, Long beforeTime) throws Exception { // 本次刷新时间 Long refrehTime = System.currentTimeMillis(); // 获取需要刷新的Mapper文件列表 List<File> fileList = this.getRefreshFile(new File(filePath), beforeTime); if (fileList.size() > 0) { log.debug("Refresh file: " + fileList.size()); } for (int i = 0; i < fileList.size(); i++) { InputStream inputStream = new FileInputStream(fileList.get(i)); String resource = fileList.get(i).getAbsolutePath(); try { // 清理原有资源，更新为自己的StrictMap方便，增量重新加载 String[] mapFieldNames = new String[]{ "mappedStatements", "caches", "resultMaps", "parameterMaps", "keyGenerators", "sqlFragments" }; for (String fieldName : mapFieldNames){ Field field = configuration.getClass().getDeclaredField(fieldName); field.setAccessible(true); Map map = ((Map)field.get(configuration)); if (!(map instanceof StrictMap)){ Map newMap = new StrictMap(StringUtils.capitalize(fieldName) + "collection"); for (Object key : map.keySet()){ try { newMap.put(key, map.get(key)); }catch(IllegalArgumentException ex){ newMap.put(key, ex.getMessage()); } } field.set(configuration, newMap); } } // 清理已加载的资源标识，方便让它重新加载。 Field loadedResourcesField = configuration.getClass().getDeclaredField("loadedResources"); loadedResourcesField.setAccessible(true); Set loadedResourcesSet = ((Set)loadedResourcesField.get(configuration)); loadedResourcesSet.remove(resource); //重新编译加载资源文件。 XMLMapperBuilder xmlMapperBuilder = new XMLMapperBuilder(inputStream, configuration, resource, configuration.getSqlFragments()); xmlMapperBuilder.parse(); } catch (Exception e) { throw new NestedIOException("Failed to parse mapping resource: '" + resource + "'", e); } finally { ErrorContext.instance().reset(); } if (log.isDebugEnabled()) { log.debug("Refresh file: " + fileList.get(i).getAbsolutePath()); log.debug("Refresh filename: " + fileList.get(i).getName()); } } if (fileList.size() > 0) { this.beforeTime = refrehTime; }}/** * 获取需要刷新的文件列表 * @param dir 目录 * @param beforeTime 上次刷新时间 * @return 刷新文件列表 */private List<File> getRefreshFile(File dir, Long beforeTime) { List<File> fileList = new ArrayList<File>(); File[] files = dir.listFiles(); if (files != null) { for (int i = 0; i < files.length; i++) { File file = files[i]; if (file.isDirectory()) { fileList.addAll(this.getRefreshFile(file, beforeTime)); } else if (file.isFile()) { if (this.checkFile(file, beforeTime)) { fileList.add(file); } } else { System.out.println("Error file." + file.getName()); } } } return fileList;}/** * 判断文件是否需要刷新 * @param file 文件 * @param beforeTime 上次刷新时间 * @return 需要刷新返回true，否则返回false */private boolean checkFile(File file, Long beforeTime) { if (file.lastModified() > beforeTime) { return true; } return false;}/** * 获取整数属性 * @param key * @return */private static int getPropInt(String key) { int i = 0; try { i = Integer.parseInt(getPropString(key)); } catch (Exception e) { } return i;}/** * 获取字符串属性 * @param key * @return */private static String getPropString(String key) { return prop == null ? null : prop.getProperty(key);}@Overridepublic void setApplicationContext(ApplicationContext applicationContext) throws BeansException { this.applicationContext = applicationContext ;}/** * 重写 org.apache.ibatis.session.Configuration.StrictMap 类 * 来自 MyBatis3.4.0版本，修改 put 方法，允许反复 put更新。 */public static class StrictMap<V> extends HashMap<String, V> { private static final long serialVersionUID = -4950446264854982944L; private String name; public StrictMap(String name, int initialCapacity, float loadFactor) { super(initialCapacity, loadFactor); this.name = name; } public StrictMap(String name, int initialCapacity) { super(initialCapacity); this.name = name; } public StrictMap(String name) { super(); this.name = name; } public StrictMap(String name, Map<String, ? extends V> m) { super(m); this.name = name; } @SuppressWarnings("unchecked") public V put(String key, V value) { // ThinkGem 如果现在状态为刷新，则刷新(先删除后添加) if (MapperRefresh.isRefresh()) { remove(key); } // ThinkGem end if (containsKey(key)) { throw new IllegalArgumentException(name + " already contains value for " + key); } if (key.contains(".")) { final String shortKey = getShortName(key); if (super.get(shortKey) == null) { super.put(shortKey, value); } else { super.put(shortKey, (V) new Ambiguity(shortKey)); } } return super.put(key, value); } public V get(Object key) { V value = super.get(key); if (value == null) { throw new IllegalArgumentException(name + " does not contain value for " + key); } if (value instanceof Ambiguity) { throw new IllegalArgumentException(((Ambiguity) value).getSubject() + " is ambiguous in " + name + " (try using the full name including the namespace, or rename one of the entries)"); } return value; } private String getShortName(String key) { final String[] keyparts = key.split("\\."); return keyparts[keyparts.length - 1]; } protected static class Ambiguity { private String subject; public Ambiguity(String subject) { this.subject = subject; } public String getSubject() { return subject; } }}public Resource[] getResource(String basePackage, String pattern) throws IOException { String packageSearchPath = ResourcePatternResolver.CLASSPATH_ALL_URL_PREFIX + ClassUtils.convertClassNameToResourcePath(applicationContext.getEnvironment().resolveRequiredPlaceholders( basePackage)) + "/" + pattern; ResourcePatternResolver resourcePatternResolver = new PathMatchingResourcePatternResolver(); Resource[] resources = resourcePatternResolver.getResources(packageSearchPath); return resources;}

}