最初启动服务后Mapper XML文件,必须重启服务才能生效,这样就大大影响了我们的开发效率。
网上同学们也有实现类似功能,但都是全部清空,全部刷新XML,这样硬件消耗比较严重,加载时间也比较长。我们只修改了几行SQL就没有必要全部加载,只需要加载修改的问题就行了。
后来为了急需解决这个问题,进行修改MyBatis源码实现Mapper XML增量刷新,直接覆盖方式实现,使用classloader的加载机制优先加载,并应用到了jeesite中,但是经过MyBatis几次升级后,不得不需要重新修改,部署也麻烦,入侵性太强。
周末有幸又重新研究下源代码将刷新部分,分离出来,实现MyBatis Mapper文件动态重新加载,只加载修改的文件,今天分享出来,不多说,看源码,注释很详细:
/** * Copyright (c) 2012-Now https://github.com/thinkgem/jeesite. */ package com.thinkgem.jeesite.mybatis.thread; import java.io.File; import java.io.FileInputStream; import java.io.FileNotFoundException; import java.io.InputStream; import java.lang.reflect.Field; import java.util.ArrayList; import java.util.HashMap; import java.util.List; import java.util.Map; import java.util.Properties; import java.util.Set; 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.log4j.Logger; import org.springframework.core.NestedIOException; import org.springframework.core.io.Resource; import com.google.common.collect.Sets; /** * 刷新MyBatis Mapper XML 线程 * @author ThinkGem * @version 2016-5-29 */ public class MapperRefresh implements java.lang.Runnable { public static Logger log = Logger.getLogger(MapperRefresh.class); private static String filename = "/mybatis-refresh.properties"; private static Properties prop = new Properties(); 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 static { try { prop.load(MapperRefresh.class.getResourceAsStream(filename)); } catch (Exception e) { e.printStackTrace(); System.out.println("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); } public static boolean isRefresh() { return refresh; } public MapperRefresh(Resource[] mapperLocations, Configuration configuration) { this.mapperLocations = mapperLocations; this.configuration = configuration; } @Override public void run() { 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 java.lang.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; System.out.println("========= 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(); } System.out.println("Refresh file: " + mappingPath + StringUtils.substringAfterLast(fileList.get(i).getAbsolutePath(), mappingPath)); if (log.isDebugEnabled()) { log.debug("Refresh file: " + fileList.get(i).getAbsolutePath()); log.debug("Refresh filename: " + fileList.get(i).getName()); } } // 如果刷新了文件,则修改刷新时间,否则不修改 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); } /** * 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); MapperRefresh.log.debug("refresh key:" + key.substring(key.lastIndexOf(".") + 1)); } // 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; } } } }
MyBatis有几个不太好的地方,是当实体类别名重名的时候,Mapper XML有错误的时候,系统启动时会一直等待无法正常启动(其实是加载失败后又重新加载,进入了死循环),这里我也顺便重写下SqlSessionFactoryBean.java文件,解决这个问题,在这个文件里也加入启动上面写的线程类:
1、修改实体类重名的时候抛出并打印异常,否则系统会一直递归造成无法启动。
2、MapperXML有错误的时候抛出并打印异常,否则系统会一直递归造成无法启动。
3、加入启动MapperRefresh.java线程服务。
/** * Copyright 2010-2015 the original author or authors. * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ package com.thinkgem.jeesite.mybatis.spring; import static org.springframework.util.Assert.notNull; import static org.springframework.util.ObjectUtils.isEmpty; import static org.springframework.util.StringUtils.hasLength; import static org.springframework.util.StringUtils.tokenizeToStringArray; import java.io.IOException; import java.sql.SQLException; import java.util.Properties; import javax.sql.DataSource; import org.apache.ibatis.builder.xml.XMLConfigBuilder; import org.apache.ibatis.builder.xml.XMLMapperBuilder; import org.apache.ibatis.executor.ErrorContext; import org.apache.ibatis.logging.Log; import org.apache.ibatis.logging.LogFactory; import org.apache.ibatis.mapping.DatabaseIdProvider; import org.apache.ibatis.mapping.Environment; import org.apache.ibatis.plugin.Interceptor; import org.apache.ibatis.reflection.factory.ObjectFactory; import org.apache.ibatis.reflection.wrapper.ObjectWrapperFactory; import org.apache.ibatis.session.Configuration; import org.apache.ibatis.session.SqlSessionFactory; import org.apache.ibatis.session.SqlSessionFactoryBuilder; import org.apache.ibatis.transaction.TransactionFactory; import org.apache.ibatis.type.TypeHandler; import org.mybatis.spring.transaction.SpringManagedTransactionFactory; import org.springframework.beans.factory.FactoryBean; import org.springframework.beans.factory.InitializingBean; import org.springframework.context.ApplicationEvent; import org.springframework.context.ApplicationListener; import org.springframework.context.ConfigurableApplicationContext; import org.springframework.context.event.ContextRefreshedEvent; import org.springframework.core.NestedIOException; import org.springframework.core.io.Resource; import org.springframework.jdbc.datasource.TransactionAwareDataSourceProxy; import com.thinkgem.jeesite.common.mybatis.thread.MapperRefresh; /** * {@code FactoryBean} that creates an MyBatis {@code SqlSessionFactory}. * This is the usual way to set up a shared MyBatis {@code SqlSessionFactory} in a Spring application context; * the SqlSessionFactory can then be passed to MyBatis-based DAOs via dependency injection. * * Either {@code DataSourceTransactionManager} or {@code JtaTransactionManager} can be used for transaction * demarcation in combination with a {@code SqlSessionFactory}. JTA should be used for transactions * which span multiple databases or when container managed transactions (CMT) are being used. * * @author Putthibong Boonbong * @author Hunter Presnall * @author Eduardo Macarron * * @see #setConfigLocation * @see #setDataSource * @version $Id$ * @modify ThinkGem 2016-5-24 来自 MyBatisSpring1.2.3版本 */ public class SqlSessionFactoryBean implements FactoryBean<SqlSessionFactory>, InitializingBean, ApplicationListener<ApplicationEvent> { private static final Log LOGGER = LogFactory.getLog(SqlSessionFactoryBean.class); private Resource configLocation; private Resource[] mapperLocations; private DataSource dataSource; private TransactionFactory transactionFactory; private Properties configurationProperties; private SqlSessionFactoryBuilder sqlSessionFactoryBuilder = new SqlSessionFactoryBuilder(); private SqlSessionFactory sqlSessionFactory; //EnvironmentAware requires spring 3.1 private String environment = SqlSessionFactoryBean.class.getSimpleName(); private boolean failFast; private Interceptor[] plugins; private TypeHandler<?>[] typeHandlers; private String typeHandlersPackage; private Class<?>[] typeAliases; private String typeAliasesPackage; private Class<?> typeAliasesSuperType; //issue #19. No default provider. private DatabaseIdProvider databaseIdProvider; private ObjectFactory objectFactory; private ObjectWrapperFactory objectWrapperFactory; /** * Sets the ObjectFactory. * * @since 1.1.2 * @param objectFactory */ public void setObjectFactory(ObjectFactory objectFactory) { this.objectFactory = objectFactory; } /** * Sets the ObjectWrapperFactory. * * @since 1.1.2 * @param objectWrapperFactory */ public void setObjectWrapperFactory(ObjectWrapperFactory objectWrapperFactory) { this.objectWrapperFactory = objectWrapperFactory; } /** * Gets the DatabaseIdProvider * * @since 1.1.0 * @return */ public DatabaseIdProvider getDatabaseIdProvider() { return databaseIdProvider; } /** * Sets the DatabaseIdProvider. * As of version 1.2.2 this variable is not initialized by default. * * @since 1.1.0 * @param databaseIdProvider */ public void setDatabaseIdProvider(DatabaseIdProvider databaseIdProvider) { this.databaseIdProvider = databaseIdProvider; } /** * Mybatis plugin list. * * @since 1.0.1 * * @param plugins list of plugins * */ public void setPlugins(Interceptor[] plugins) { this.plugins = plugins; } /** * Packages to search for type aliases. * * @since 1.0.1 * * @param typeAliasesPackage package to scan for domain objects * */ public void setTypeAliasesPackage(String typeAliasesPackage) { this.typeAliasesPackage = typeAliasesPackage; } /** * Super class which domain objects have to extend to have a type alias created. * No effect if there is no package to scan configured. * * @since 1.1.2 * * @param typeAliasesSuperType super class for domain objects * */ public void setTypeAliasesSuperType(Class<?> typeAliasesSuperType) { this.typeAliasesSuperType = typeAliasesSuperType; } /** * Packages to search for type handlers. * * @since 1.0.1 * * @param typeHandlersPackage package to scan for type handlers * */ public void setTypeHandlersPackage(String typeHandlersPackage) { this.typeHandlersPackage = typeHandlersPackage; } /** * Set type handlers. They must be annotated with {@code MappedTypes} and optionally with {@code MappedJdbcTypes} * * @since 1.0.1 * * @param typeHandlers Type handler list */ public void setTypeHandlers(TypeHandler<?>[] typeHandlers) { this.typeHandlers = typeHandlers; } /** * List of type aliases to register. They can be annotated with {@code Alias} * * @since 1.0.1 * * @param typeAliases Type aliases list */ public void setTypeAliases(Class<?>[] typeAliases) { this.typeAliases = typeAliases; } /** * If true, a final check is done on Configuration to assure that all mapped * statements are fully loaded and there is no one still pending to resolve * includes. Defaults to false. * * @since 1.0.1 * * @param failFast enable failFast */ public void setFailFast(boolean failFast) { this.failFast = failFast; } /** * Set the location of the MyBatis {@code SqlSessionFactory} config file. A typical value is * "WEB-INF/mybatis-configuration.xml". */ public void setConfigLocation(Resource configLocation) { this.configLocation = configLocation; } /** * Set locations of MyBatis mapper files that are going to be merged into the {@code SqlSessionFactory} * configuration at runtime. * * This is an alternative to specifying "<sqlmapper>" entries in an MyBatis config file. * This property being based on Spring's resource abstraction also allows for specifying * resource patterns here: e.g. "classpath*:sqlmap/*-mapper.xml". */ public void setMapperLocations(Resource[] mapperLocations) { this.mapperLocations = mapperLocations; } /** * Set optional properties to be passed into the SqlSession configuration, as alternative to a * {@code <properties>} tag in the configuration xml file. This will be used to * resolve placeholders in the config file. */ public void setConfigurationProperties(Properties sqlSessionFactoryProperties) { this.configurationProperties = sqlSessionFactoryProperties; } /** * Set the JDBC {@code DataSource} that this instance should manage transactions for. The {@code DataSource} * should match the one used by the {@code SqlSessionFactory}: for example, you could specify the same * JNDI DataSource for both. * * A transactional JDBC {@code Connection} for this {@code DataSource} will be provided to application code * accessing this {@code DataSource} directly via {@code DataSourceUtils} or {@code DataSourceTransactionManager}. * * The {@code DataSource} specified here should be the target {@code DataSource} to manage transactions for, not * a {@code TransactionAwareDataSourceProxy}. Only data access code may work with * {@code TransactionAwareDataSourceProxy}, while the transaction manager needs to work on the * underlying target {@code DataSource}. If there's nevertheless a {@code TransactionAwareDataSourceProxy} * passed in, it will be unwrapped to extract its target {@code DataSource}. * */ public void setDataSource(DataSource dataSource) { if (dataSource instanceof TransactionAwareDataSourceProxy) { // If we got a TransactionAwareDataSourceProxy, we need to perform // transactions for its underlying target DataSource, else data // access code won't see properly exposed transactions (i.e. // transactions for the target DataSource). this.dataSource = ((TransactionAwareDataSourceProxy) dataSource).getTargetDataSource(); } else { this.dataSource = dataSource; } } /** * Sets the {@code SqlSessionFactoryBuilder} to use when creating the {@code SqlSessionFactory}. * * This is mainly meant for testing so that mock SqlSessionFactory classes can be injected. By * default, {@code SqlSessionFactoryBuilder} creates {@code DefaultSqlSessionFactory} instances. * */ public void setSqlSessionFactoryBuilder(SqlSessionFactoryBuilder sqlSessionFactoryBuilder) { this.sqlSessionFactoryBuilder = sqlSessionFactoryBuilder; } /** * Set the MyBatis TransactionFactory to use. Default is {@code SpringManagedTransactionFactory} * * The default {@code SpringManagedTransactionFactory} should be appropriate for all cases: * be it Spring transaction management, EJB CMT or plain JTA. If there is no active transaction, * SqlSession operations will execute SQL statements non-transactionally. * * <b>It is strongly recommended to use the default {@code TransactionFactory}.</b> If not used, any * attempt at getting an SqlSession through Spring's MyBatis framework will throw an exception if * a transaction is active. * * @see SpringManagedTransactionFactory * @param transactionFactory the MyBatis TransactionFactory */ public void setTransactionFactory(TransactionFactory transactionFactory) { this.transactionFactory = transactionFactory; } /** * <b>NOTE:</b> This class <em>overrides</em> any {@code Environment} you have set in the MyBatis * config file. This is used only as a placeholder name. The default value is * {@code SqlSessionFactoryBean.class.getSimpleName()}. * * @param environment the environment name */ public void setEnvironment(String environment) { this.environment = environment; } /** * {@inheritDoc} */ @Override public void afterPropertiesSet() throws Exception { notNull(dataSource, "Property 'dataSource' is required"); notNull(sqlSessionFactoryBuilder, "Property 'sqlSessionFactoryBuilder' is required"); this.sqlSessionFactory = buildSqlSessionFactory(); } /** * Build a {@code SqlSessionFactory} instance. * * The default implementation uses the standard MyBatis {@code XMLConfigBuilder} API to build a * {@code SqlSessionFactory} instance based on an Reader. * * @return SqlSessionFactory * @throws IOException if loading the config file failed */ protected SqlSessionFactory buildSqlSessionFactory() throws IOException { Configuration configuration; XMLConfigBuilder xmlConfigBuilder = null; if (this.configLocation != null) { xmlConfigBuilder = new XMLConfigBuilder(this.configLocation.getInputStream(), null, this.configurationProperties); configuration = xmlConfigBuilder.getConfiguration(); } else { if (LOGGER.isDebugEnabled()) { LOGGER.debug("Property 'configLocation' not specified, using default MyBatis Configuration"); } configuration = new Configuration(); configuration.setVariables(this.configurationProperties); } if (this.objectFactory != null) { configuration.setObjectFactory(this.objectFactory); } if (this.objectWrapperFactory != null) { configuration.setObjectWrapperFactory(this.objectWrapperFactory); } if (hasLength(this.typeAliasesPackage)) { String[] typeAliasPackageArray = tokenizeToStringArray(this.typeAliasesPackage, ConfigurableApplicationContext.CONFIG_LOCATION_DELIMITERS); for (String packageToScan : typeAliasPackageArray) { // ThinkGem 修改实体类重名的时候抛出并打印异常,否则系统会一直递归造成无法启动 try { configuration.getTypeAliasRegistry().registerAliases(packageToScan, typeAliasesSuperType == null ? Object.class : typeAliasesSuperType); } catch (Exception ex) { LOGGER.error("Scanned package: '" + packageToScan + "' for aliases", ex); throw new NestedIOException("Scanned package: '" + packageToScan + "' for aliases", ex); } finally { ErrorContext.instance().reset(); } // ThinkGem end if (LOGGER.isDebugEnabled()) { LOGGER.debug("Scanned package: '" + packageToScan + "' for aliases"); } } } if (!isEmpty(this.typeAliases)) { for (Class<?> typeAlias : this.typeAliases) { configuration.getTypeAliasRegistry().registerAlias(typeAlias); if (LOGGER.isDebugEnabled()) { LOGGER.debug("Registered type alias: '" + typeAlias + "'"); } } } if (!isEmpty(this.plugins)) { for (Interceptor plugin : this.plugins) { configuration.addInterceptor(plugin); if (LOGGER.isDebugEnabled()) { LOGGER.debug("Registered plugin: '" + plugin + "'"); } } } if (hasLength(this.typeHandlersPackage)) { String[] typeHandlersPackageArray = tokenizeToStringArray(this.typeHandlersPackage, ConfigurableApplicationContext.CONFIG_LOCATION_DELIMITERS); for (String packageToScan : typeHandlersPackageArray) { configuration.getTypeHandlerRegistry().register(packageToScan); if (LOGGER.isDebugEnabled()) { LOGGER.debug("Scanned package: '" + packageToScan + "' for type handlers"); } } } if (!isEmpty(this.typeHandlers)) { for (TypeHandler<?> typeHandler : this.typeHandlers) { configuration.getTypeHandlerRegistry().register(typeHandler); if (LOGGER.isDebugEnabled()) { LOGGER.debug("Registered type handler: '" + typeHandler + "'"); } } } if (xmlConfigBuilder != null) { try { xmlConfigBuilder.parse(); if (LOGGER.isDebugEnabled()) { LOGGER.debug("Parsed configuration file: '" + this.configLocation + "'"); } } catch (Exception ex) { throw new NestedIOException("Failed to parse config resource: " + this.configLocation, ex); } finally { ErrorContext.instance().reset(); } } if (this.transactionFactory == null) { this.transactionFactory = new SpringManagedTransactionFactory(); } configuration.setEnvironment(new Environment(this.environment, this.transactionFactory, this.dataSource)); if (this.databaseIdProvider != null) { try { configuration.setDatabaseId(this.databaseIdProvider.getDatabaseId(this.dataSource)); } catch (SQLException e) { throw new NestedIOException("Failed getting a databaseId", e); } } if (!isEmpty(this.mapperLocations)) { for (Resource mapperLocation : this.mapperLocations) { if (mapperLocation == null) { continue; } try { XMLMapperBuilder xmlMapperBuilder = new XMLMapperBuilder(mapperLocation.getInputStream(), configuration, mapperLocation.toString(), configuration.getSqlFragments()); xmlMapperBuilder.parse(); } catch (Exception e) { // ThinkGem MapperXML有错误的时候抛出并打印异常,否则系统会一直递归造成无法启动 LOGGER.error("Failed to parse mapping resource: '" + mapperLocation + "'", e); throw new NestedIOException("Failed to parse mapping resource: '" + mapperLocation + "'", e); } finally { ErrorContext.instance().reset(); } if (LOGGER.isDebugEnabled()) { LOGGER.debug("Parsed mapper file: '" + mapperLocation + "'"); } } // ThinkGem 启动刷新MapperXML定时器(有助于开发者调试)。 new MapperRefresh(this.mapperLocations, configuration).run(); } else { if (LOGGER.isDebugEnabled()) { LOGGER.debug("Property 'mapperLocations' was not specified or no matching resources found"); } } return this.sqlSessionFactoryBuilder.build(configuration); } /** * {@inheritDoc} */ @Override public SqlSessionFactory getObject() throws Exception { if (this.sqlSessionFactory == null) { afterPropertiesSet(); } return this.sqlSessionFactory; } /** * {@inheritDoc} */ @Override public Class<? extends SqlSessionFactory> getObjectType() { return this.sqlSessionFactory == null ? SqlSessionFactory.class : this.sqlSessionFactory.getClass(); } /** * {@inheritDoc} */ @Override public boolean isSingleton() { return true; } /** * {@inheritDoc} */ @Override public void onApplicationEvent(ApplicationEvent event) { if (failFast && event instanceof ContextRefreshedEvent) { // fail-fast -> check all statements are completed this.sqlSessionFactory.getConfiguration().getMappedStatementNames(); } } }
相关推荐
总的来说,通过合理配置IDEA的自动构建选项,以及Mybatis Plus的热加载设置,我们可以实现在修改Mapper XML文件后,无需重启Tomcat即可看到更新效果,大大提高开发效率。如果遇到XML文件未被自动检测到更新的情况,...
"Spring+mvc+mybatis Mapper xml自动加载"这个主题聚焦于如何在开发过程中优化配置,使得改动Mapper XML文件后,无需重启Tomcat服务器,就可以立即生效,从而提高开发效率。 Spring MVC是Spring框架的一部分,它...
MyBatis热部署Mapper增量更新是一种提高开发效率的方法,它允许开发者在运行时动态地替换或更新mapper文件,而无需中断服务。这种方式可以显著减少开发过程中的等待时间,提升开发体验。 要实现MyBatis的Mapper热...
"mybatis xml文件自动生成"是开发过程中的一个重要环节,它可以帮助开发者提高效率,减少手动编写XML映射文件和对应的POJO(Plain Old Java Object)类的工作量。 MyBatis的Mapper文件是其核心组成部分之一,它包含...
本篇文章将深入探讨MyBatis的Mapper和XML文件生成,以及如何使用`mybatis-generator-core-1.3.2`工具进行自动化生成。 首先,让我们理解Mapper接口。Mapper接口是MyBatis中的一个关键概念,它允许开发者定义数据库...
在Spring Boot集成MyBatis的过程中,`mapper.xml`配置文件起着至关重要的作用。它用于定义SQL语句,实现数据库的CRUD操作。本示例将深入探讨如何配置`mapper.xml`,并提供新增、修改、删除、查询及分页查询的实践...
mybatis修改了mapper xml不用重启tomcat,热发布热更新.zip
mybatis基本文件xml、mapper等自动生成工具 可自己根据自己的项目路径自行配置文件夹路径,本DEMO是使用的mysql数据库,可自行更换其他数据源 本DEMO会自动生成dao、model、mapper、xml文件,自带基本方法,可自动...
4. **整合**:最后,将生成的文件导入到Maven项目中,并在项目中配置MyBatis的SqlSessionFactory,确保能正确加载Mapper XML文件。 关于`mysql-connector-java-5.1.38.jar`,这是一个MySQL的JDBC驱动包,它是连接...
idea好用的插件:Free Mybatis自动对应mapper层的xml文件
MyBatis Generator(MBG)是一款强大的工具,用于自动生成MyBatis的Mapper接口、XML映射文件以及对应的实体类。这款工具极大地提高了开发效率,减少了手动编写这些基础代码的工作量,使得开发者能够更专注于业务逻辑...
标题和描述所提及的问题是关于如何在Mapper.xml文件中处理字符串形式的参数,这些参数由逗号分隔,并在`AND`语句中拼接`OR`子句来实现动态查询。这种场景在处理用户多选过滤条件时非常常见,比如在一个搜索框中,...
Mybatis 是一个流行的Java持久层框架,它简化了数据库操作,允许开发者将SQL语句直接写在XML映射文件中,提供了动态SQL的功能。在Eclipse这样的集成开发环境中,为了提高开发效率,我们可以配置Mybatis的插件,使得...
本文将深入探讨如何在SpringBoot项目中整合MyBatis,并实现自动生成Mapper.xml文件、DAO接口以及对应的Model类。 首先,我们需要确保项目已经集成了SpringBoot和MyBatis的基础配置。这通常涉及以下步骤: 1. 添加...
4. **代码生成器**:MyBatis提供了一个强大的代码生成器(MyBatis Generator,MBG),可以根据数据库表结构自动生成Mapper接口、Mapper XML文件以及实体类。这大大减少了手动编码的工作量,保证了代码的规范性和一致...
Mybatis Mapper通过动态代理机制,使得我们可以直接在XML映射文件中定义SQL,然后在接口中声明对应的方法,系统会在运行时自动生成实现类,这样就消除了对实现类的直接依赖。 下面我们将详细探讨Mybatis Mapper的几...
在Spring Boot和MyBatis框架集成的开发过程中,自动化生成DAO层接口与对应的XML配置文件可以极大地提高开发效率。下面将详细介绍如何实现这一功能,并深入探讨相关知识点。 首先,Spring Boot是一个快速开发框架,...
3. **Mapper接口和XML映射文件**:Mapper接口是DAO接口的具体实现,它通过MyBatis的动态SQL功能来执行SQL。XML映射文件则包含了具体的SQL语句,包括元素(用于设置参数)、元素(用于获取结果集)。MBG会根据表的...
MyBatis Mapper映射文件
用mybatis-plus的自动生成器,我们一般只用到entity和mapperXML,其他mapper接口和service类都要自己写。 可以下载之后,根据自己表生成mapperXML,然后用全局替换来修改一些细节。