Bug 118429 [DataBinding] Validation should use IStatus, not just Strings
In order to use data binding in Workbench or IDE dialogs and preference pages, we need validation in terms of IStatus objects. Using strings is too simplistic. For example, look at the wizard for creating a new class. You will get a warning if the class name does not start with an uppercase letter, or if you don't provide a package name, but you will still be able to click "Finish" to proceed anyway. (Note that IStatus is currently not on the classpath, we need to re-introduce the dependency on org.eclipse.equinox.common, which contains IStatus etc.)
bundles/org.eclipse.core.databinding/src/org/eclipse/core/databinding/DataBindingContext.java
}
	/**
	 * Binds two observable lists using converter and validator as specified in
	 * bindSpec. If bindSpec is null, a default converter and validator is used.
	 * 
	 * @param targetObservableList
	 * @param modelObservableList
	 * @param bindSpec
	 *            the bind spec, or null. Any bindSpec object must not be reused
	 *            or changed after it is passed to #bind.
	 * @return The Binding that manages this data flow
	 */
	public Binding bindList(IObservableList targetObservableList,
			IObservableList modelObservableList, BindSpec bindSpec) {
		if (bindSpec == null) {
			bindSpec = new BindSpec();
		}
		fillBindSpecDefaults(this, bindSpec, targetObservableList.getElementType(), modelObservableList.getElementType());
		Binding result = new ListBinding(this, targetObservableList,
				modelObservableList, bindSpec);
        bindings.add(result);
		return result;
	}
	/**
	 * Tries to create a converter that can convert from values of type
	 * fromType. Returns <code>null</code> if no converter could be created.
	 * Either toType or modelDescription can be <code>null</code>, but not
	 * both. The implementation of this method will iterate over the registered
	 * bind support factories in reverse order, passing the given arguments to
	 * {@link BindSupportFactory#createConverter(Object, Object)}. The first