Exception in thread "main" org.xmlpull.v1.XmlPullP

[xmlpull]XmlPull常见错误

编写者	日期	关键词
郑昀@ultrapower	2005-9-28	Xmlpull kxml java

 

Xmlpull官方站点：http://www.xmlpull.org/

优点：不必等整个文档解析完成，部分求值结果早就可以开始反馈给用户。

What Is It?

XmlPull project is dedicated to be a site for

• for general Pull parsing promotion/education (including StAX) and in particular to contain easy-to-reuse samples and code fragments

• a resource for discussing new ideas and concepts related to pull parsing

• a java namespace (org.xmlpull.*) and project location of a free implementation of the event object API and Factories, based on the StAX XMLStreamReade and old Common API for XML Pull Parsing

• as java namespace and project location of StAX and XmlPull based utilities and samples such as:
  - providing an XML stream from a DOM tree
  - a DOM builder
  - SAX adapter
  - JUnit tests

• as a maintenance resource for the existing XmlPull interface

常见错误一：XmlPullParserException:resource not found

网络中有很多人问到同样一个问题：

为什么我们在调用

XmlPullParserFactory factory = XmlPullParserFactory.newInstance();

时，总是得到这样的错误：

错误提示：

Exception in thread "main" org.xmlpull.v1.XmlPullParserException: caused by: org.xmlpull.v1.XmlPullParserException: resource not found: /META-INF/services/org.xmlpull.v1.XmlPullParserFactory make sure that parser implementing XmlPull API is available     at org.xmlpull.v1.XmlPullParserFactory.newInstance(XmlPullParserFactory.java:294)

虽然从http://www.xmlpull.org/v1/doc/api/org/xmlpull/v1/XmlPullParserFactory.html

看到了他们自己的注解：

XmlPullParserFactory的注释：

If no name of parser factory was passed (or is null) it will try to find name by searching in CLASSPATH for META-INF/services/org.xmlpull.v1.XmlPullParserFactory resource that should contain a comma separated list of class names of factories or parsers to try (in order from left to the right). If none found, it will throw an exception.  NOTE:In J2SE or J2EE environments, you may want to use newInstance(property, classLoaderCtx) where first argument is System.getProperty(XmlPullParserFactory.PROPERTY_NAME) and second is Thread.getContextClassLoader().getClass() .

看来它确实需要寻找这么一个资源：

META-INF/services/org.xmlpull.v1.XmlPullParserFactory

。但又没说如何才能找到它。

解决办法

将http://kxml.sourceforge.net/

下载的kxml2.jar加到你的项目中即可。这时候再调用

XmlPullParserFactory factory = XmlPullParserFactory.newInstance(

                            System.getProperty(XmlPullParserFactory.PROPERTY_NAME),

                   Thread.currentThread().getContextClassLoader().getClass() );

就通过了。

kxml2.jar就包含了META-INF/services/org.xmlpull.v1.XmlPullParserFactory文件，它的内容其实就是一句话：

org.kxml2.io.KXmlParser,org.kxml2.io.KXmlSerializer