SQuirreL Configure：无法初始化类org.apache.phoenix.jdbc.PhoenixDriver

Question

当我配置SQuirreL（3.7.1）时，抛出此错误：

could not initial class org.apache.phoenix.jdbc.PhoenixDriver


java.lang.NoClassDefFoundError: Could not initialize class org.apache.phoenix.jdbc.PhoenixDriver
    at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
    at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62)
    at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
    at java.lang.reflect.Constructor.newInstance(Constructor.java:423)
    at java.lang.Class.newInstance(Class.java:442)
    at net.sourceforge.squirrel_sql.fw.sql.SQLDriverManager.registerSQLDriver(SQLDriverManager.java:75)
    at net.sourceforge.squirrel_sql.fw.sql.SQLDriverManager$MyDriverListener.propertyChange(SQLDriverManager.java:197)
    at java.beans.PropertyChangeSupport.fire(PropertyChangeSupport.java:335)
    at java.beans.PropertyChangeSupport.firePropertyChange(PropertyChangeSupport.java:327)
    at java.beans.PropertyChangeSupport.firePropertyChange(PropertyChangeSupport.java:263)
    at net.sourceforge.squirrel_sql.fw.util.PropertyChangeReporter.firePropertyChange(PropertyChangeReporter.java:65)
    at net.sourceforge.squirrel_sql.fw.sql.SQLDriver.setJarFileNames(SQLDriver.java:277)
    at net.sourceforge.squirrel_sql.client.gui.db.DriverInternalFrame.applyFromDialog(DriverInternalFrame.java:246)
    at net.sourceforge.squirrel_sql.client.gui.db.DriverInternalFrame.performOk(DriverInternalFrame.java:221)
    at net.sourceforge.squirrel_sql.client.gui.db.DriverInternalFrame.access$200(DriverInternalFrame.java:57)
    at net.sourceforge.squirrel_sql.client.gui.db.DriverInternalFrame$3.actionPerformed(DriverInternalFrame.java:373)
    at javax.swing.AbstractButton.fireActionPerformed(AbstractButton.java:2022)
    at javax.swing.AbstractButton$Handler.actionPerformed(AbstractButton.java:2348)
    at javax.swing.DefaultButtonModel.fireActionPerformed(DefaultButtonModel.java:402)
    at javax.swing.DefaultButtonModel.setPressed(DefaultButtonModel.java:259)
    at javax.swing.plaf.basic.BasicButtonListener.mouseReleased(BasicButtonListener.java:252)
    at java.awt.Component.processMouseEvent(Component.java:6535)
    at javax.swing.JComponent.processMouseEvent(JComponent.java:3324)
    at java.awt.Component.processEvent(Component.java:6300)
    at java.awt.Container.processEvent(Container.java:2236)
    at java.awt.Component.dispatchEventImpl(Component.java:4891)
    at java.awt.Container.dispatchEventImpl(Container.java:2294)
    at java.awt.Component.dispatchEvent(Component.java:4713)
    at java.awt.LightweightDispatcher.retargetMouseEvent(Container.java:4888)
    at java.awt.LightweightDispatcher.processMouseEvent(Container.java:4525)
    at java.awt.LightweightDispatcher.dispatchEvent(Container.java:4466)
    at java.awt.Container.dispatchEventImpl(Container.java:2280)
    at java.awt.Window.dispatchEventImpl(Window.java:2750)
    at java.awt.Component.dispatchEvent(Component.java:4713)
    at java.awt.EventQueue.dispatchEventImpl(EventQueue.java:758)
    at java.awt.EventQueue.access$500(EventQueue.java:97)
    at java.awt.EventQueue$3.run(EventQueue.java:709)
    at java.awt.EventQueue$3.run(EventQueue.java:703)
    at java.security.AccessController.doPrivileged(Native Method)
    at java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:76)
    at java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:86)
    at java.awt.EventQueue$4.run(EventQueue.java:731)
    at java.awt.EventQueue$4.run(EventQueue.java:729)
    at java.security.AccessController.doPrivileged(Native Method)
    at java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:76)
    at java.awt.EventQueue.dispatchEvent(EventQueue.java:728)
    at net.sourceforge.squirrel_sql.client.Main$1.dispatchEvent(Main.java:99)
    at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:201)
    at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:116)
    at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:105)
    at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:101)
    at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:93)
    at java.awt.EventDispatchThread.run(EventDispatchThread.java:82)

这是详细日志：

Answer 1

该错误消息表明JVM已经尝试并且无法对org.apache.phoenix.jdbc.PhoenixDriver类执行静态初始化。

如果JVM无法静态初始化一个类，可能是因为它所依赖的类丢失了，或者是由于static { ... }块中的某些代码引发了异常，那么JVM将不会再次尝试加载该类。 如您所见，它将仅引发NoClassDefFoundError 。 您将需要重新启动JVM才能重新尝试加载驱动程序类。 重新启动SQuirreL，尝试再次连接到Phoenix，看看您是否第一次收到其他错误消息。

查看此类的源代码，如果（a）缺少slf4j JAR，（b）您正在运行的应用程序具有一个SecurityManager拒绝添加关闭挂钩的权限，或者（c）JVM失败，则静态初始化可能会失败创建PhoenixEmbeddedDriver类PhoenixEmbeddedDriver的实例。 超类依赖于commons-logging，因此另一个可能的原因可能是缺少commons-logging JAR。

但是，这些只是我对问题所在的猜测。 据我所知，唯一可以确定的方法是重新启动SQuirreL并查看您是否第一次收到不同的异常消息。