FormLayout NoClassDefFoundError

Formlayout does not seem to be working. How can I fix that

Exception in thread "AWT-EventQueue-0" java.lang.NoClassDefFoundError: com/jgoodies/forms/layout/FormLayout

at TestForm.$$$setupUI$$$(TestForm.java)

at TestForm.<init>(TestForm.java:20)

at Main$1.actionPerformed(Main.java:29)

at java.desktop/javax.swing.AbstractButton.fireActionPerformed(AbstractButton.java:1972)

at java.desktop/javax.swing.AbstractButton$Handler.actionPerformed(AbstractButton.java:2314)

at java.desktop/javax.swing.DefaultButtonModel.fireActionPerformed(DefaultButtonModel.java:407)

at java.desktop/javax.swing.DefaultButtonModel.setPressed(DefaultButtonModel.java:262)

at java.desktop/javax.swing.plaf.basic.BasicButtonListener.mouseReleased(BasicButtonListener.java:279)

at java.desktop/java.awt.Component.processMouseEvent(Component.java:6620)

at java.desktop/javax.swing.JComponent.processMouseEvent(JComponent.java:3398)

at java.desktop/java.awt.Component.processEvent(Component.java:6385)

at java.desktop/java.awt.Container.processEvent(Container.java:2266)

at java.desktop/java.awt.Component.dispatchEventImpl(Component.java:4995)

at java.desktop/java.awt.Container.dispatchEventImpl(Container.java:2324)

at java.desktop/java.awt.Component.dispatchEvent(Component.java:4827)

at java.desktop/java.awt.LightweightDispatcher.retargetMouseEvent(Container.java:4948)

at java.desktop/java.awt.LightweightDispatcher.processMouseEvent(Container.java:4575)

at java.desktop/java.awt.LightweightDispatcher.dispatchEvent(Container.java:4516)

at java.desktop/java.awt.Container.dispatchEventImpl(Container.java:2310)

at java.desktop/java.awt.Window.dispatchEventImpl(Window.java:2780)

at java.desktop/java.awt.Component.dispatchEvent(Component.java:4827)

at java.desktop/java.awt.EventQueue.dispatchEventImpl(EventQueue.java:775)

at java.desktop/java.awt.EventQueue$4.run(EventQueue.java:720)

at java.desktop/java.awt.EventQueue$4.run(EventQueue.java:714)

at java.base/java.security.AccessController.doPrivileged(AccessController.java:400)

at java.base/java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:87)

at java.base/java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:98)

at java.desktop/java.awt.EventQueue$5.run(EventQueue.java:747)

at java.desktop/java.awt.EventQueue$5.run(EventQueue.java:745)

at java.base/java.security.AccessController.doPrivileged(AccessController.java:400)

at java.base/java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:87)

at java.desktop/java.awt.EventQueue.dispatchEvent(EventQueue.java:744)

at java.desktop/java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:203)

at java.desktop/java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:124)

at java.desktop/java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:113)

at java.desktop/java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:109)

at java.desktop/java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:101)

at java.desktop/java.awt.EventDispatchThread.run(EventDispatchThread.java:90)

Caused by: java.lang.ClassNotFoundException: com.jgoodies.forms.layout.FormLayout

at java.base/jdk.internal.loader.BuiltinClassLoader.loadClass(BuiltinClassLoader.java:641)

at java.base/jdk.internal.loader.ClassLoaders$AppClassLoader.loadClass(ClassLoaders.java:188)

at java.base/java.lang.ClassLoader.loadClass(ClassLoader.java:521)