Bug 92988 [Viewers] potential NPE in AbstractTreeViewer
I0426, found with FindBugs 1. AbstractTreeViewer line 832 invokes "siblings.length", but the "if" statement above implies that siblings could be null here. 2. StringFieldEditor line 187 does an unnecessary null check since Text.getText() never returns null (FindBugs was using this to point to line 190 as a potential NPE).
bundles/org.eclipse.jface/src/org/eclipse/jface/preference/StringFieldEditor.java
String txt = textField.getText();
        if (txt == null)
            result = false;
        result = (txt.trim().length() > 0) || emptyStringAllowed;
        
        result = result && doCheckState();
        if (result)
            clearErrorMessage();
        else
            showErrorMessage(errorMessage);
        return result;
    }
    /**
     * Hook for subclasses to do specific state checks.
     * <p>
     * The default implementation of this framework method does
     * nothing and returns <code>true</code>.  Subclasses should 
     * override this method to specific state checks.
     * </p>
     *
     * @return <code>true</code> if the field value is valid,
     *   and <code>false</code> if invalid
     */
    protected boolean doCheckState() {
        return true;
    }
    /**
     * Fills this field editor's basic controls into the given parent.
     * <p>
     * The string field implementation of this <code>FieldEditor</code>