Bug 144225 [FieldAssist] NullPointerException in ContentProposalAdapter$ContentProposalPopup.open()
I am using Eclipse 3.2RC6 and was playing around with the org.eclipse.jface.fieldassist package. I wanted to implement a simple auto-complete textfield with the ContentProposalAdapter class. But if the first letter which is entered in the textfield does not yield any proposals, the call to getSelectedProposal() in line 859 of ContentProposalAdapter.java returns null and therefore a NPE is thrown, rather than just not showing the popup at all. The following snippet shows this behaviour (just type any letter except "p"): import org.eclipse.jface.fieldassist.ContentProposalAdapter; import org.eclipse.jface.fieldassist.IContentProposal; import org.eclipse.jface.fieldassist.IContentProposalProvider; import org.eclipse.jface.fieldassist.TextContentAdapter; import org.eclipse.swt.SWT; import org.eclipse.swt.layout.FillLayout; import org.eclipse.swt.widgets.Display; import org.eclipse.swt.widgets.Shell; import org.eclipse.swt.widgets.Text; public class ExampleSnippet { public static void main(String[] args) { Display display = new Display(); Shell shell = new Shell(display); shell.setLayout(new FillLayout()); Text text = new Text(shell, SWT.NONE); ContentProposalAdapter adapter = new ContentProposalAdapter(text, new TextContentAdapter(), new TextProposalProvider(), null, null); adapter.setProposalAcceptanceStyle(ContentProposalAdapter.PROPOSAL_REPLACE); shell.setSize(200, text.getSize().y); shell.open(); while (!shell.isDisposed()) { if (!display.readAndDispatch()) display.sleep(); } display.dispose(); } } class TextProposalProvider implements IContentProposalProvider { private String str = "Proposal"; public IContentProposal[] getProposals(String contents, int position) { IContentProposal[] proposals; if (str.toLowerCase().startsWith(contents.toLowerCase())) { proposals = new IContentProposal[1]; proposals[0] = new IContentProposal() { public String getContent() { return str; } public int getCursorPosition() { return str.length(); } public String getDescription() { return null; } public String getLabel() { return null; } }; } else { proposals = new IContentProposal[0]; } return proposals; } }
bundles/org.eclipse.jface/src/org/eclipse/jface/fieldassist/ContentProposalAdapter.java
*/
	public static final int PROPOSAL_REPLACE = 2;
	/**
	 * Indicates that the contents of the control should not be modified when a
	 * proposal is chosen. This is typically used when a client needs more
	 * specialized behavior when a proposal is chosen. In this case, clients
	 * typically register an IContentProposalListener so that they are notified
	 * when a proposal is chosen.
	 */
	public static final int PROPOSAL_IGNORE = 3;
	/**
	 * Indicates that there should be no filter applied as keys are typed in the
	 * popup.
	 */
	public static final int FILTER_NONE = 1;
	/**
	 * Indicates that a single character filter applies as keys are typed in the
	 * popup.
	 */
	public static final int FILTER_CHARACTER = 2;
	/**
	 * Indicates that a cumulative filter applies as keys are typed in the
	 * popup. That is, each character typed will be added to the filter.
	 */
	public static final int FILTER_CUMULATIVE = 3;
	/*
	 * Set to <code>true</code> to use a Table with SWT.VIRTUAL. This is a
	 * workaround for https://bugs.eclipse.org/bugs/show_bug.cgi?id=98585#c40
	 * The corresponding SWT bug is
	 * https://bugs.eclipse.org/bugs/show_bug.cgi?id=90321