Bug 219635 [CellEditors] CheckboxEditor flips state when tabbed into
bundles/org.eclipse.jface/src/org/eclipse/jface/viewers/CheckboxCellEditor.java
}
    /**
     * The <code>CheckboxCellEditor</code> implementation of
     * this <code>CellEditor</code> framework method returns
     * the checkbox setting wrapped as a <code>Boolean</code>.
     *
     * @return the Boolean checkbox value
     */
    protected Object doGetValue() {
        return value ? Boolean.TRUE : Boolean.FALSE;
    }
    /* (non-Javadoc)
     * Method declared on CellEditor.
     */
    protected void doSetFocus() {
        
    }
    /**
     * The <code>CheckboxCellEditor</code> implementation of
     * this <code>CellEditor</code> framework method accepts
     * a value wrapped as a <code>Boolean</code>.
     *
     * @param value a Boolean value
     */
    protected void doSetValue(Object value) {
        Assert.isTrue(value instanceof Boolean);
        this.value = ((Boolean) value).booleanValue();
    }
}