java.lang.NoClassDefFoundError:

Question

java.lang.NoClassDefFoundError: com/genuitec/eclipse/core/ui/action/LicenseValidatingAction
at java.lang.ClassLoader.defineClass1(Native Method)
at java.lang.ClassLoader.defineClass(ClassLoader.java:621)
at org.eclipse.osgi.internal.baseadaptor.DefaultClassLoader.defineClass(DefaultClassLoader.java:188)
at org.eclipse.osgi.baseadaptor.loader.ClasspathManager.defineClassHoldingLock(ClasspathManager.java:626)
at org.eclipse.osgi.baseadaptor.loader.ClasspathManager.defineClass(ClasspathManager.java:608)
at org.eclipse.osgi.baseadaptor.loader.ClasspathManager.findClassImpl(ClasspathManager.java:562)
at org.eclipse.osgi.baseadaptor.loader.ClasspathManager.findLocalClassImpl(ClasspathManager.java:486)
at org.eclipse.osgi.baseadaptor.loader.ClasspathManager.findLocalClass(ClasspathManager.java:459)
at org.eclipse.osgi.internal.baseadaptor.DefaultClassLoader.findLocalClass(DefaultClassLoader.java:216)
at org.eclipse.osgi.internal.loader.BundleLoader.findLocalClass(BundleLoader.java:400)
at org.eclipse.osgi.internal.loader.BundleLoader.findClassInternal(BundleLoader.java:476)
at org.eclipse.osgi.internal.loader.BundleLoader.findClass(BundleLoader.java:429)
at org.eclipse.osgi.internal.loader.BundleLoader.findClass(BundleLoader.java:417)

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Answer 1

看错误是不是少jar包？还有就是会不会是调用这个类的那个类有代码写错了？