报错原因:
Exception in thread "main" java.lang.NoClassDefFoundError: org/apache/commons/lang/exception/NestableRuntimeException
at java.lang.ClassLoader.defineClass1(Native Method)
at java.lang.ClassLoader.defineClass(ClassLoader.java:760)
at java.security.SecureClassLoader.defineClass(SecureClassLoader.java:142)
at java.net.URLClassLoader.defineClass(URLClassLoader.java:467)
at java.net.URLClassLoader.access$100(URLClassLoader.java:73)
at java.net.URLClassLoader$1.run(URLClassLoader.java:368)
at java.net.URLClassLoader$1.run(URLClassLoader.java:362)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(URLClassLoader.java:361)
at java.lang.ClassLoader.loadClass(ClassLoader.java:424)
at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:331)
at java.lang.ClassLoader.loadClass(ClassLoader.java:357)
at dao.Dao.main(Dao.java:43)
Caused by: java.lang.ClassNotFoundException: org.apache.commons.lang.exception.NestableRuntimeException
at java.net.URLClassLoader.findClass(URLClassLoader.java:381)
at java.lang.ClassLoader.loadClass(ClassLoader.java:424)
at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:331)
at java.lang.ClassLoader.loadClass(ClassLoader.java:357)
... 13 more
问题代码:
public static void main(String[] args) {
Dao dao=new Dao();
List<Province> provinceList=dao.findAllProvince();
System.out.println(provinceList);
String json=JSONArray.fromObject(provinceList).toString();
}
根据内容介绍应该是说jar包没有导,导致 String json=JSONArray.fromObject(provinceList).toString(); 报错
但是我的jar包是已经完全导入的了
初步解决:
jar包版本过高,全部换了低版本jar可以运行。以后再研究具体是什么原因。