org.xml.sax.SAXParseException: Failed to read schema document 的原因分析与解决方法

现象:

org.xml.sax.SAXParseException: schema_reference.4: Failed to read schema documen

t 'http://www.springframework.org/schema/beans/spring-beans-3.1.xsd', because 1)

 could not find the document; 2) the document could not be read; 3) the root ele

ment of the document is not <xsd:schema>.

分析： 

参考http://blog.csdn.net/bluishglc/article/details/7596118 

这篇文章分析的比较深入，具体原因为： 

根据xx.jar\META-INF\spring.schemas文件，先在本地查找相关xsd文件，如果本地没有，则通过网络去获取，实际上上面问题往往出现在没有网络的服务器上（本地正常，传到服务器上，而服务器一般是不能访问外网的） 

但该文章并没有讲清楚更具体的处理措施，只是说了最好用maven的shade打包插件而不是assembly

处理：

必须在 <transformers> 里面加上下面内容

<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>

才会出现“shade能够将所有jar里的spring.schemas文件进行合并，在最终生成的单一jar包里，spring.schemas包含了所有出现过的版本的集合！”的效果

参考 

http://blog.csdn.net/bluishglc/article/details/7596118 

http://mapserver000-gmail-com.iteye.com/blog/1182499

http://shuhucy.iteye.com/blog/1771684

http://stackoverflow.com/questions/8523997/unable-to-locate-spring-namespacehandler-for-xml-schema-namespace-http-www-sp/8574629#8574629

http://maven.apache.org/plugins/maven-shade-plugin/examples/resource-transformers.html

http://maven.apache.org/plugins/maven-shade-plugin/