Bug 21631 JavaUI.createTypeDialog() should provide default message [dialogs]
2.0 Release If you use JavaUI.createTypeDialog() to create a new (single selection) type dialog, and then open the dialog, the open will fail silently. The dialog cannot be succesfully opened unless you send setMessage() to the dialog before you open it. This behaviour should be documented, or, preferably, a default message ("Please select a type/class/interface") should be provided.
org.eclipse.jdt.ui/ui/org/eclipse/jdt/ui/JavaUI.java
/*******************************************************************************
 * Copyright (c) 2000, 2002 International Business Machines Corp. and others.
 * All rights reserved. This program and the accompanying materials 
 * are made available under the terms of the Common Public License v1.0 
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/cpl-v10.html
 * 
 * Contributors:
 *     IBM Corporation - initial API and implementation
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package org.eclipse.jdt.ui;
import java.net.URL;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Iterator;
import java.util.List;
import org.eclipse.core.resources.IProject;
import org.eclipse.core.runtime.IPath;
import org.eclipse.swt.widgets.Shell;
import org.eclipse.jface.operation.IRunnableContext;
import org.eclipse.jface.util.Assert;
import org.eclipse.ui.IEditorPart;
import org.eclipse.ui.PartInitException;
import org.eclipse.ui.dialogs.ElementListSelectionDialog;
import org.eclipse.ui.dialogs.SelectionDialog;
import org.eclipse.ui.texteditor.IDocumentProvider;
import org.eclipse.jdt.core.IBufferFactory;
import org.eclipse.jdt.core.IJavaElement;
import org.eclipse.jdt.core.IJavaProject;
import org.eclipse.jdt.core.IPackageFragmentRoot;