起因

项目中同时依赖了Spring和MyBatis，并使用mybatis-spring集成MyBatis和Spring。

使用maven打包为可执行jar文件运行，打包插件为：maven-shade-plugin。

<!-- 打包可执行jar文件 -->

<plugin>

        <groupId>org.apache.maven.plugins</groupId>

        <artifactId>maven-shade-plugin</artifactId>

        <version>3.1.0</version>

        <executions>

                <execution>

                        <phase>package</phase>

                        <goals>

                                <goal>shade</goal>

                        </goals>

                        <configuration>

                                <transformers>

                                        <transformer implementation="org.apache.maven.plugins.shade.resource.ManifestResourceTransformer">

                                                <mainClass>org.chench.Main</mainClass>

                                        </transformer>

                                </transformers>

                        </configuration>

                </execution>

        </executions>

</plugin>

但是在执行java -jar package.jar命令时报错：

2017-10-23 10:40:54,942  INFO [main] - Loading XML bean definitions from class path resource [spring-mybatis.xml]

2017-10-23 10:40:54,960 DEBUG [main] - Using JAXP provider [com.sun.org.apache.xerces.internal.jaxp.DocumentBuilderFactoryImpl]

2017-10-23 10:40:55,011 DEBUG [main] - Loading schema mappings from [META-INF/spring.schemas]

2017-10-23 10:40:55,013 DEBUG [main] - Loaded schema mappings: {http://mybatis.org/schema/mybatis-spring.xsd=org/mybatis/spring/config/mybatis-spring-1.2.xsd, http://mybatis.org/schema/mybatis-spring-1.2.xsd=org/mybatis/spring/config/mybatis-spring-1.2.xsd}

2017-10-23 10:40:56,458 DEBUG [main] - Loading bean definitions

2017-10-23 10:40:56,471 DEBUG [main] - Loaded NamespaceHandler mappings: {http://mybatis.org/schema/mybatis-spring=org.mybatis.spring.config.NamespaceHandler}

Exception in thread "main" org.springframework.beans.factory.parsing.BeanDefinitionParsingException: Configuration problem: Unable to locate Spring NamespaceHandler for XML schema namespace [http://www.springframework.org/schema/context]

Offending resource: class path resource [spring-mybatis.xml]

        at org.springframework.beans.factory.parsing.FailFastProblemReporter.error(FailFastProblemReporter.java:72)

        at org.springframework.beans.factory.parsing.ReaderContext.error(ReaderContext.java:119)

        at org.springframework.beans.factory.parsing.ReaderContext.error(ReaderContext.java:111)

        at org.springframework.beans.factory.xml.BeanDefinitionParserDelegate.error(BeanDefinitionParserDelegate.java:281)

        at org.springframework.beans.factory.xml.BeanDefinitionParserDelegate.parseCustomElement(BeanDefinitionParserDelegate.java:1363)

        at org.springframework.beans.factory.xml.BeanDefinitionParserDelegate.parseCustomElement(BeanDefinitionParserDelegate.java:1352)

        at org.springframework.beans.factory.xml.DefaultBeanDefinitionDocumentReader.parseBeanDefinitions(DefaultBeanDefinitionDocumentReader.java:178)

        at org.springframework.beans.factory.xml.DefaultBeanDefinitionDocumentReader.doRegisterBeanDefinitions(DefaultBeanDefinitionDocumentReader.java:148)

        at org.springframework.beans.factory.xml.DefaultBeanDefinitionDocumentReader.registerBeanDefinitions(DefaultBeanDefinitionDocumentReader.java:98)

        at org.springframework.beans.factory.xml.XmlBeanDefinitionReader.registerBeanDefinitions(XmlBeanDefinitionReader.java:507)

        at org.springframework.beans.factory.xml.XmlBeanDefinitionReader.doLoadBeanDefinitions(XmlBeanDefinitionReader.java:391)

        at org.springframework.beans.factory.xml.XmlBeanDefinitionReader.loadBeanDefinitions(XmlBeanDefinitionReader.java:335)

        at org.springframework.beans.factory.xml.XmlBeanDefinitionReader.loadBeanDefinitions(XmlBeanDefinitionReader.java:303)

        at org.springframework.beans.factory.support.AbstractBeanDefinitionReader.loadBeanDefinitions(AbstractBeanDefinitionReader.java:187)

        at org.springframework.beans.factory.support.AbstractBeanDefinitionReader.loadBeanDefinitions(AbstractBeanDefinitionReader.java:223)

        at org.springframework.beans.factory.support.AbstractBeanDefinitionReader.loadBeanDefinitions(AbstractBeanDefinitionReader.java:194)

        at org.springframework.beans.factory.support.AbstractBeanDefinitionReader.loadBeanDefinitions(AbstractBeanDefinitionReader.java:258)

        at org.springframework.context.support.AbstractXmlApplicationContext.loadBeanDefinitions(AbstractXmlApplicationContext.java:128)

        at org.springframework.context.support.AbstractXmlApplicationContext.loadBeanDefinitions(AbstractXmlApplicationContext.java:94)

        at org.springframework.context.support.AbstractRefreshableApplicationContext.refreshBeanFactory(AbstractRefreshableApplicationContext.java:133)

        at org.springframework.context.support.AbstractApplicationContext.obtainFreshBeanFactory(AbstractApplicationContext.java:620)

        at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:521)

        at org.springframework.context.support.ClassPathXmlApplicationContext.<init>(ClassPathXmlApplicationContext.java:144)

        at org.springframework.context.support.ClassPathXmlApplicationContext.<init>(ClassPathXmlApplicationContext.java:85)

        at com.lenovo.moc.dbupdater.MocDbUpdater.main(MocDbUpdater.java:47)

原因分析

项目同时依赖了mybatis-spring.jar和spring-context.jar，spring-tx.jar等一系列Spring框架组件。

它们都存在同名文件：META-INF/spring.schemas，META-INF/spring.handlers。

正是因为存在这些同名文件，所以maven在打包时就可能会将mybatis-spring.jar中的文件覆盖掉spring-xxx.jar中的对应文件。

显然，在mybatis-spring.jar中spring.schemas定义的命名空间与spring-xxx.jar中spring.schemas定义的命名空间是不一样的，这就导致在程序启动

加载Spring容器时无法找到指定schema定义从而报错！

mybatis-spring/META-INF/spring.schemas内容：

http\://mybatis.org/schema/mybatis-spring-1.2.xsd=org/mybatis/spring/config/mybatis-spring-1.2.xsd

http\://mybatis.org/schema/mybatis-spring.xsd=org/mybatis/spring/config/mybatis-spring-1.2.xsd

mybatis-spring/META-INF/spring.handlers内容：

http\://mybatis.org/schema/mybatis-spring=org.mybatis.spring.config.NamespaceHandler

解决方案

在maven-shade-plugin插件中通过Resource Transformers将所有的spring.schemas文件中的内容都合并到一起。

<!-- 打包可执行jar文件 -->

<plugin>

        <groupId>org.apache.maven.plugins</groupId>

        <artifactId>maven-shade-plugin</artifactId>

        <version>3.1.0</version>

        <executions>

                <execution>

                        <phase>package</phase>

                        <goals>

                                <goal>shade</goal>

                        </goals>

                        <configuration>

                                <transformers>

                                        <!-- 将schema文件内容合并到一个文件中，而不是直接覆盖 -->

                                        <transformer implementation="org.apache.maven.plugins.shade.resource.AppendingTransformer">

                                                <resource>META-INF/spring.handlers</resource>

                                        </transformer>

                                        <transformer implementation="org.apache.maven.plugins.shade.resource.AppendingTransformer">

                                                <resource>META-INF/spring.schemas</resource>

                                        </transformer>

                                        <transformer implementation="org.apache.maven.plugins.shade.resource.ManifestResourceTransformer">

                                                <mainClass>org.chench.Main</mainClass>

                                        </transformer>

                                </transformers>

                        </configuration>

                </execution>

        </executions>

</plugin>

添加配置之后打包结果：

META-INF/spring.schemas内容：

http\://mybatis.org/schema/mybatis-spring-1.2.xsd=org/mybatis/spring/config/mybatis-spring-1.2.xsd

http\://mybatis.org/schema/mybatis-spring.xsd=org/mybatis/spring/config/mybatis-spring-1.2.xsd

http\://www.springframework.org/schema/context/spring-context-2.5.xsd=org/springframework/context/config/spring-context.xsd

http\://www.springframework.org/schema/context/spring-context-3.0.xsd=org/springframework/context/config/spring-context.xsd

http\://www.springframework.org/schema/context/spring-context-3.1.xsd=org/springframework/context/config/spring-context.xsd

http\://www.springframework.org/schema/context/spring-context-3.2.xsd=org/springframework/context/config/spring-context.xsd

http\://www.springframework.org/schema/context/spring-context-4.0.xsd=org/springframework/context/config/spring-context.xsd

http\://www.springframework.org/schema/context/spring-context-4.1.xsd=org/springframework/context/config/spring-context.xsd

http\://www.springframework.org/schema/context/spring-context-4.2.xsd=org/springframework/context/config/spring-context.xsd

http\://www.springframework.org/schema/context/spring-context-4.3.xsd=org/springframework/context/config/spring-context.xsd

http\://www.springframework.org/schema/context/spring-context.xsd=org/springframework/context/config/spring-context.xsd

http\://www.springframework.org/schema/jee/spring-jee-2.0.xsd=org/springframework/ejb/config/spring-jee.xsd

http\://www.springframework.org/schema/jee/spring-jee-2.5.xsd=org/springframework/ejb/config/spring-jee.xsd

http\://www.springframework.org/schema/jee/spring-jee-3.0.xsd=org/springframework/ejb/config/spring-jee.xsd

http\://www.springframework.org/schema/jee/spring-jee-3.1.xsd=org/springframework/ejb/config/spring-jee.xsd

http\://www.springframework.org/schema/jee/spring-jee-3.2.xsd=org/springframework/ejb/config/spring-jee.xsd

http\://www.springframework.org/schema/jee/spring-jee-4.0.xsd=org/springframework/ejb/config/spring-jee.xsd

http\://www.springframework.org/schema/jee/spring-jee-4.1.xsd=org/springframework/ejb/config/spring-jee.xsd

http\://www.springframework.org/schema/jee/spring-jee-4.2.xsd=org/springframework/ejb/config/spring-jee.xsd

http\://www.springframework.org/schema/jee/spring-jee-4.3.xsd=org/springframework/ejb/config/spring-jee.xsd

http\://www.springframework.org/schema/jee/spring-jee.xsd=org/springframework/ejb/config/spring-jee.xsd

http\://www.springframework.org/schema/lang/spring-lang-2.0.xsd=org/springframework/scripting/config/spring-lang.xsd

http\://www.springframework.org/schema/lang/spring-lang-2.5.xsd=org/springframework/scripting/config/spring-lang.xsd

http\://www.springframework.org/schema/lang/spring-lang-3.0.xsd=org/springframework/scripting/config/spring-lang.xsd

http\://www.springframework.org/schema/lang/spring-lang-3.1.xsd=org/springframework/scripting/config/spring-lang.xsd

http\://www.springframework.org/schema/lang/spring-lang-3.2.xsd=org/springframework/scripting/config/spring-lang.xsd

http\://www.springframework.org/schema/lang/spring-lang-4.0.xsd=org/springframework/scripting/config/spring-lang.xsd

http\://www.springframework.org/schema/lang/spring-lang-4.1.xsd=org/springframework/scripting/config/spring-lang.xsd

http\://www.springframework.org/schema/lang/spring-lang-4.2.xsd=org/springframework/scripting/config/spring-lang.xsd

http\://www.springframework.org/schema/lang/spring-lang-4.3.xsd=org/springframework/scripting/config/spring-lang.xsd

http\://www.springframework.org/schema/lang/spring-lang.xsd=org/springframework/scripting/config/spring-lang.xsd

http\://www.springframework.org/schema/task/spring-task-3.0.xsd=org/springframework/scheduling/config/spring-task.xsd

http\://www.springframework.org/schema/task/spring-task-3.1.xsd=org/springframework/scheduling/config/spring-task.xsd

http\://www.springframework.org/schema/task/spring-task-3.2.xsd=org/springframework/scheduling/config/spring-task.xsd

http\://www.springframework.org/schema/task/spring-task-4.0.xsd=org/springframework/scheduling/config/spring-task.xsd

http\://www.springframework.org/schema/task/spring-task-4.1.xsd=org/springframework/scheduling/config/spring-task.xsd

http\://www.springframework.org/schema/task/spring-task-4.2.xsd=org/springframework/scheduling/config/spring-task.xsd

http\://www.springframework.org/schema/task/spring-task-4.3.xsd=org/springframework/scheduling/config/spring-task.xsd

http\://www.springframework.org/schema/task/spring-task.xsd=org/springframework/scheduling/config/spring-task.xsd

http\://www.springframework.org/schema/cache/spring-cache-3.1.xsd=org/springframework/cache/config/spring-cache.xsd

http\://www.springframework.org/schema/cache/spring-cache-3.2.xsd=org/springframework/cache/config/spring-cache.xsd

http\://www.springframework.org/schema/cache/spring-cache-4.0.xsd=org/springframework/cache/config/spring-cache.xsd

http\://www.springframework.org/schema/cache/spring-cache-4.1.xsd=org/springframework/cache/config/spring-cache.xsd

http\://www.springframework.org/schema/cache/spring-cache-4.2.xsd=org/springframework/cache/config/spring-cache.xsd

http\://www.springframework.org/schema/cache/spring-cache-4.3.xsd=org/springframework/cache/config/spring-cache.xsd

http\://www.springframework.org/schema/cache/spring-cache.xsd=org/springframework/cache/config/spring-cache.xsd

http\://www.springframework.org/schema/aop/spring-aop-2.0.xsd=org/springframework/aop/config/spring-aop.xsd

http\://www.springframework.org/schema/aop/spring-aop-2.5.xsd=org/springframework/aop/config/spring-aop.xsd

http\://www.springframework.org/schema/aop/spring-aop-3.0.xsd=org/springframework/aop/config/spring-aop.xsd

http\://www.springframework.org/schema/aop/spring-aop-3.1.xsd=org/springframework/aop/config/spring-aop.xsd

http\://www.springframework.org/schema/aop/spring-aop-3.2.xsd=org/springframework/aop/config/spring-aop.xsd

http\://www.springframework.org/schema/aop/spring-aop-4.0.xsd=org/springframework/aop/config/spring-aop.xsd

http\://www.springframework.org/schema/aop/spring-aop-4.1.xsd=org/springframework/aop/config/spring-aop.xsd

http\://www.springframework.org/schema/aop/spring-aop-4.2.xsd=org/springframework/aop/config/spring-aop.xsd

http\://www.springframework.org/schema/aop/spring-aop-4.3.xsd=org/springframework/aop/config/spring-aop.xsd

http\://www.springframework.org/schema/aop/spring-aop.xsd=org/springframework/aop/config/spring-aop.xsd

http\://www.springframework.org/schema/beans/spring-beans-2.0.xsd=org/springframework/beans/factory/xml/spring-beans.xsd

http\://www.springframework.org/schema/beans/spring-beans-2.5.xsd=org/springframework/beans/factory/xml/spring-beans.xsd

http\://www.springframework.org/schema/beans/spring-beans-3.0.xsd=org/springframework/beans/factory/xml/spring-beans.xsd

http\://www.springframework.org/schema/beans/spring-beans-3.1.xsd=org/springframework/beans/factory/xml/spring-beans.xsd

http\://www.springframework.org/schema/beans/spring-beans-3.2.xsd=org/springframework/beans/factory/xml/spring-beans.xsd

http\://www.springframework.org/schema/beans/spring-beans-4.0.xsd=org/springframework/beans/factory/xml/spring-beans.xsd

http\://www.springframework.org/schema/beans/spring-beans-4.1.xsd=org/springframework/beans/factory/xml/spring-beans.xsd

http\://www.springframework.org/schema/beans/spring-beans-4.2.xsd=org/springframework/beans/factory/xml/spring-beans.xsd

http\://www.springframework.org/schema/beans/spring-beans-4.3.xsd=org/springframework/beans/factory/xml/spring-beans.xsd

http\://www.springframework.org/schema/beans/spring-beans.xsd=org/springframework/beans/factory/xml/spring-beans.xsd

http\://www.springframework.org/schema/tool/spring-tool-2.0.xsd=org/springframework/beans/factory/xml/spring-tool.xsd

http\://www.springframework.org/schema/tool/spring-tool-2.5.xsd=org/springframework/beans/factory/xml/spring-tool.xsd

http\://www.springframework.org/schema/tool/spring-tool-3.0.xsd=org/springframework/beans/factory/xml/spring-tool.xsd

http\://www.springframework.org/schema/tool/spring-tool-3.1.xsd=org/springframework/beans/factory/xml/spring-tool.xsd

http\://www.springframework.org/schema/tool/spring-tool-3.2.xsd=org/springframework/beans/factory/xml/spring-tool.xsd

http\://www.springframework.org/schema/tool/spring-tool-4.0.xsd=org/springframework/beans/factory/xml/spring-tool.xsd

http\://www.springframework.org/schema/tool/spring-tool-4.1.xsd=org/springframework/beans/factory/xml/spring-tool.xsd

http\://www.springframework.org/schema/tool/spring-tool-4.2.xsd=org/springframework/beans/factory/xml/spring-tool.xsd

http\://www.springframework.org/schema/tool/spring-tool-4.3.xsd=org/springframework/beans/factory/xml/spring-tool.xsd

http\://www.springframework.org/schema/tool/spring-tool.xsd=org/springframework/beans/factory/xml/spring-tool.xsd

http\://www.springframework.org/schema/util/spring-util-2.0.xsd=org/springframework/beans/factory/xml/spring-util.xsd

http\://www.springframework.org/schema/util/spring-util-2.5.xsd=org/springframework/beans/factory/xml/spring-util.xsd

http\://www.springframework.org/schema/util/spring-util-3.0.xsd=org/springframework/beans/factory/xml/spring-util.xsd

http\://www.springframework.org/schema/util/spring-util-3.1.xsd=org/springframework/beans/factory/xml/spring-util.xsd

http\://www.springframework.org/schema/util/spring-util-3.2.xsd=org/springframework/beans/factory/xml/spring-util.xsd

http\://www.springframework.org/schema/util/spring-util-4.0.xsd=org/springframework/beans/factory/xml/spring-util.xsd

http\://www.springframework.org/schema/util/spring-util-4.1.xsd=org/springframework/beans/factory/xml/spring-util.xsd

http\://www.springframework.org/schema/util/spring-util-4.2.xsd=org/springframework/beans/factory/xml/spring-util.xsd

http\://www.springframework.org/schema/util/spring-util-4.3.xsd=org/springframework/beans/factory/xml/spring-util.xsd

http\://www.springframework.org/schema/util/spring-util.xsd=org/springframework/beans/factory/xml/spring-util.xsd

http\://www.springframework.org/schema/tx/spring-tx-2.0.xsd=org/springframework/transaction/config/spring-tx.xsd

http\://www.springframework.org/schema/tx/spring-tx-2.5.xsd=org/springframework/transaction/config/spring-tx.xsd

http\://www.springframework.org/schema/tx/spring-tx-3.0.xsd=org/springframework/transaction/config/spring-tx.xsd

http\://www.springframework.org/schema/tx/spring-tx-3.1.xsd=org/springframework/transaction/config/spring-tx.xsd

http\://www.springframework.org/schema/tx/spring-tx-3.2.xsd=org/springframework/transaction/config/spring-tx.xsd

http\://www.springframework.org/schema/tx/spring-tx-4.0.xsd=org/springframework/transaction/config/spring-tx.xsd

http\://www.springframework.org/schema/tx/spring-tx-4.1.xsd=org/springframework/transaction/config/spring-tx.xsd

http\://www.springframework.org/schema/tx/spring-tx-4.2.xsd=org/springframework/transaction/config/spring-tx.xsd

http\://www.springframework.org/schema/tx/spring-tx-4.3.xsd=org/springframework/transaction/config/spring-tx.xsd

http\://www.springframework.org/schema/tx/spring-tx.xsd=org/springframework/transaction/config/spring-tx.xsd

http\://www.springframework.org/schema/jdbc/spring-jdbc-3.0.xsd=org/springframework/jdbc/config/spring-jdbc.xsd

http\://www.springframework.org/schema/jdbc/spring-jdbc-3.1.xsd=org/springframework/jdbc/config/spring-jdbc.xsd

http\://www.springframework.org/schema/jdbc/spring-jdbc-3.2.xsd=org/springframework/jdbc/config/spring-jdbc.xsd

http\://www.springframework.org/schema/jdbc/spring-jdbc-4.0.xsd=org/springframework/jdbc/config/spring-jdbc.xsd

http\://www.springframework.org/schema/jdbc/spring-jdbc-4.1.xsd=org/springframework/jdbc/config/spring-jdbc.xsd

http\://www.springframework.org/schema/jdbc/spring-jdbc-4.2.xsd=org/springframework/jdbc/config/spring-jdbc.xsd

http\://www.springframework.org/schema/jdbc/spring-jdbc-4.3.xsd=org/springframework/jdbc/config/spring-jdbc.xsd

http\://www.springframework.org/schema/jdbc/spring-jdbc.xsd=org/springframework/jdbc/config/spring-jdbc.xsd

http\://www.alibaba.com/schema/stat.xsd=META-INF/stat.xsd

META-INF/spring.handlers内容：

http\://mybatis.org/schema/mybatis-spring=org.mybatis.spring.config.NamespaceHandler

http\://www.springframework.org/schema/context=org.springframework.context.config.ContextNamespaceHandler

http\://www.springframework.org/schema/jee=org.springframework.ejb.config.JeeNamespaceHandler

http\://www.springframework.org/schema/lang=org.springframework.scripting.config.LangNamespaceHandler

http\://www.springframework.org/schema/task=org.springframework.scheduling.config.TaskNamespaceHandler

http\://www.springframework.org/schema/cache=org.springframework.cache.config.CacheNamespaceHandler

http\://www.springframework.org/schema/aop=org.springframework.aop.config.AopNamespaceHandler

http\://www.springframework.org/schema/c=org.springframework.beans.factory.xml.SimpleConstructorNamespaceHandler

http\://www.springframework.org/schema/p=org.springframework.beans.factory.xml.SimplePropertyNamespaceHandler

http\://www.springframework.org/schema/util=org.springframework.beans.factory.xml.UtilNamespaceHandler

http\://www.springframework.org/schema/tx=org.springframework.transaction.config.TxNamespaceHandler

http\://www.springframework.org/schema/jdbc=org.springframework.jdbc.config.JdbcNamespaceHandler

http\://www.alibaba.com/schema/stat=com.alibaba.druid.support.spring.stat.config.DruidStatNamespaceHandler

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