protected void addViewParameters(
FacesContext ctx, String viewId, Map<String, List<String>> existingParameters) {
UIViewRoot currentRoot = ctx.getViewRoot();
String currentViewId = currentRoot.getViewId();
Collection<UIViewParameter> toViewParams;
Collection<UIViewParameter> currentViewParams;
boolean currentIsSameAsNew = false;
currentViewParams = ViewMetadata.getViewParameters(currentRoot);
if (currentViewId.equals(viewId)) {
currentIsSameAsNew = true;
toViewParams = currentViewParams;
} else {
ViewDeclarationLanguage pdl = getViewDeclarationLanguage(ctx, viewId);
ViewMetadata viewMetadata = pdl.getViewMetadata(ctx, viewId);
UIViewRoot root = viewMetadata.createMetadataView(ctx);
toViewParams = ViewMetadata.getViewParameters(root);
}
if (toViewParams.isEmpty()) {
return;
}
for (UIViewParameter viewParam : toViewParams) {
String value;
// don't bother looking at view parameter if it's been overridden
if (existingParameters.containsKey(viewParam.getName())) {
continue;
} else if (paramHasValueExpression(viewParam)) {
value = viewParam.getStringValueFromModel(ctx);
} else {
// Anonymous view parameter:
// Get string value from UIViewParameter instance stored in current view
if (currentIsSameAsNew) {
value = viewParam.getStringValue(ctx);
}
// ...or transfer string value from matching UIViewParameter instance stored in current view
else {
value = getStringValueToTransfer(ctx, viewParam, currentViewParams);
}
}
if (value != null) {
List<String> existing = existingParameters.get(viewParam.getName());
if (existing == null) {
existing = new ArrayList<String>(4);
existingParameters.put(viewParam.getName(), existing);
}
existing.add(value);
}
}
}
private static String getStringValueToTransfer(
FacesContext context, UIViewParameter param, Collection<UIViewParameter> viewParams) {
if (viewParams != null && !viewParams.isEmpty()) {
for (UIViewParameter candidate : viewParams) {
if ((null != candidate.getName() && null != param.getName())
&& candidate.getName().equals(param.getName())) {
return candidate.getStringValue(context);
} else {
return param.getStringValue(context);
}
}
}
return null;
}