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Exception in thread "main" java.lang.ExceptionInInitializerError
at MTest.main(MTest.java:14)
Caused by: com.sun.org.apache.commons.logging.LogConfigurationException: com.sun.org.apache.commons.logging.LogConfigurationException: java.lang.NullPointerException (Caused by java.lang.NullPointerException) (Caused by com.sun.org.apache.commons.logging.LogConfigurationException: java.lang.NullPointerException (Caused by java.lang.NullPointerException))
at com.sun.org.apache.commons.logging.impl.LogFactoryImpl.newInstance(LogFactoryImpl.java:543)
at com.sun.org.apache.commons.logging.impl.LogFactoryImpl.getInstance(LogFactoryImpl.java:235)
at com.sun.org.apache.commons.logging.impl.LogFactoryImpl.getInstance(LogFactoryImpl.java:209)
at com.sun.org.apache.commons.logging.LogFactory.getLog(LogFactory.java:351)
at com.sun.org.apache.commons.beanutils.BeanUtils.<clinit>(BeanUtils.java:111)
... 1 more
Caused by: com.sun.org.apache.commons.logging.LogConfigurationException: java.lang.NullPointerException (Caused by java.lang.NullPointerException)
at com.sun.org.apache.commons.logging.impl.LogFactoryImpl.getLogConstructor(LogFactoryImpl.java:397)
at com.sun.org.apache.commons.logging.impl.LogFactoryImpl.newInstance(LogFactoryImpl.java:529)
... 5 more
Caused by: java.lang.NullPointerException
at com.sun.org.apache.commons.logging.impl.LogFactoryImpl.getLogConstructor(LogFactoryImpl.java:374)
... 6 more
我看你的报错信息,好像是用的com.sun.org.apache.commons.logging.LogConfigurationException
你没有将common-beanutils.jar加入你的类路径,因此你的代码会导入 com.sun.org.apache.commons.beanutils.BeanUtils。它本来应该导入的是 org.apache.commons.beanutils.BeanUtils。你只要加入 common-beanutils.jar 就可以了
这个错误然后又报了空指针,我把import改成了java.lang.*错误变了
Exception in thread "main" java.lang.Error: Unresolved compilation problems:
InvocationTargetException cannot be resolved to a type
e cannot be resolved at MTest.main(MTest.java:32)
我import是这样的
import java.lang.*;
import java.util.Iterator;
import java.util.Map;
import java.util.Set;import com.sun.org.apache.commons.beanutils.BeanUtils;
彻底无语了
你要引用org.apache.commons.beanutils.BeanUtils;
而不是com.sun.org.apache.commons.beanutils.BeanUtils;