org.apache.commons.logging.LogFactory

Spring3.1启动时报错：?

Exception in thread "main" java.lang.NoClassDefFoundError: org/apache/commons/logging/LogFactory
	at org.springframework.context.support.AbstractApplicationContext.<init>(AbstractApplicationContext.java:161)
	at org.springframework.context.support.AbstractRefreshableApplicationContext.<init>(AbstractRefreshableApplicationContext.java:90)
	at org.springframework.context.support.AbstractRefreshableConfigApplicationContext.<init>(AbstractRefreshableConfigApplicationContext.java:59)
	at org.springframework.context.support.AbstractXmlApplicationContext.<init>(AbstractXmlApplicationContext.java:61)
	at org.springframework.context.support.ClassPathXmlApplicationContext.<init>(ClassPathXmlApplicationContext.java:136)
	at org.springframework.context.support.ClassPathXmlApplicationContext.<init>(ClassPathXmlApplicationContext.java:83)
	at com.syxp.yjjkService.thread.Thread.start(Thread.java:39)
	at com.syxp.yjjkService.thread.Thread.main(Thread.java:45)
Caused by: java.lang.ClassNotFoundException: org.apache.commons.logging.LogFactory
	at java.net.URLClassLoader$1.run(Unknown Source)
	at java.security.AccessController.doPrivileged(Native Method)
	at java.net.URLClassLoader.findClass(Unknown Source)
	at java.lang.ClassLoader.loadClass(Unknown Source)
	at sun.misc.Launcher$AppClassLoader.loadClass(Unknown Source)
	at java.lang.ClassLoader.loadClass(Unknown Source)
	... 8 more

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