Bug 36902 [preferences] IllegalArgumentException in JavaEditorHoverConfigurationBlock$3.keyReleased
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/preferences/JavaEditorHoverConfigurationBlock.java
import org.eclipse.swt.events.ModifyEvent;
import org.eclipse.swt.events.ModifyListener;
import org.eclipse.swt.events.SelectionEvent;
import org.eclipse.swt.events.SelectionListener;
import org.eclipse.swt.graphics.FontMetrics;
import org.eclipse.swt.graphics.GC;
import org.eclipse.swt.graphics.Point;
import org.eclipse.swt.layout.GridData;
import org.eclipse.swt.layout.GridLayout;
import org.eclipse.swt.widgets.Button;
import org.eclipse.swt.widgets.Composite;
import org.eclipse.swt.widgets.Control;
import org.eclipse.swt.widgets.Label;
import org.eclipse.swt.widgets.List;
import org.eclipse.swt.widgets.Text;
import org.eclipse.jface.action.Action;
import org.eclipse.jface.dialogs.Dialog;
import org.eclipse.jface.preference.IPreferenceStore;
import org.eclipse.jface.text.Assert;
import org.eclipse.jdt.ui.PreferenceConstants;
import org.eclipse.jdt.internal.ui.JavaPlugin;
import org.eclipse.jdt.internal.ui.dialogs.StatusInfo;
import org.eclipse.jdt.internal.ui.dialogs.StatusUtil;
import org.eclipse.jdt.internal.ui.text.java.hover.JavaEditorTextHoverDescriptor;
/**
 * Configures Java Editor hover preferences.
 * 
 * @since 2.1
 */
class JavaEditorHoverConfigurationBlock {