/**
* THIS METHOD IS NOT PART OF THE WICKET PUBLIC API. DO NOT USE IT.
*
* <p>Temporarily replaces the response with a StringResponse to capture the header output for
* this part of the stream and pass it to {@link IHeaderResponse}.
*
* @see org.apache.wicket.MarkupContainer#renderNext(org.apache.wicket.markup.MarkupStream)
*/
@Override
protected final boolean renderNext(MarkupStream markupStream) {
StringResponse markupHeaderResponse = new StringResponse();
Response oldResponse = getResponse();
RequestCycle.get().setResponse(markupHeaderResponse);
try {
boolean ret = super.renderNext(markupStream);
getHeaderResponse().render(new PageHeaderItem(markupHeaderResponse.getBuffer()));
return ret;
} finally {
RequestCycle.get().setResponse(oldResponse);
}
}
/**
* First render the body of the component. And if it is the header component of a Page (compared
* to a Panel or Border), then get the header sections from all component in the hierarchy and
* render them as well.
*/
@Override
public final void onComponentTagBody(MarkupStream markupStream, ComponentTag openTag) {
// We are able to automatically add <head> to the page if it is
// missing. But we only want to add it, if we have content to be
// written to its body. Thus we first write the output into a
// StringResponse and if not empty, we copy it to the original
// web response.
// Temporarily replace the web response with a String response
final Response webResponse = getResponse();
try {
// Create a (string) response for all headers contributed by any component on the Page.
final StringResponse response = new StringResponse();
getRequestCycle().setResponse(response);
IHeaderResponse headerResponse = getHeaderResponse();
if (!response.equals(headerResponse.getResponse())) {
getRequestCycle().setResponse(headerResponse.getResponse());
}
// Render the header sections of all components on the page
AbstractHeaderRenderStrategy.get()
.renderHeader(this, new HeaderStreamState(markupStream, openTag), getPage());
// Close the header response before rendering the header container itself
// See https://issues.apache.org/jira/browse/WICKET-3728
headerResponse.close();
// Cleanup extraneous CR and LF from the response
CharSequence output = getCleanResponse(response);
// Automatically add <head> if necessary
if (output.length() > 0) {
if (renderOpenAndCloseTags()) {
webResponse.write("<head>");
}
webResponse.write(output);
if (renderOpenAndCloseTags()) {
webResponse.write("</head>");
}
}
} finally {
// Restore the original response
getRequestCycle().setResponse(webResponse);
}
}
/**
* Runs the configured {@link IResponseFilter}s over the constructed Ajax response
*
* @param contentResponse the Ajax {@link Response} body
* @return filtered response
*/
private AppendingStringBuffer invokeResponseFilters(final StringResponse contentResponse) {
AppendingStringBuffer responseBuffer = new AppendingStringBuffer(contentResponse.getBuffer());
List<IResponseFilter> responseFilters =
Application.get().getRequestCycleSettings().getResponseFilters();
if (responseFilters != null) {
for (IResponseFilter filter : responseFilters) {
responseBuffer = filter.filter(responseBuffer);
}
}
return responseBuffer;
}
/**
* @param response
* @return Cleaned up response
*/
private CharSequence getCleanResponse(final StringResponse response) {
CharSequence output = response.getBuffer();
if (output.length() > 0) {
if (output.charAt(0) == '\r') {
for (int i = 2; i < output.length(); i += 2) {
char ch = output.charAt(i);
if (ch != '\r') {
output = output.subSequence(i - 2, output.length());
break;
}
}
} else if (output.charAt(0) == '\n') {
for (int i = 1; i < output.length(); i++) {
char ch = output.charAt(i);
if (ch != '\n') {
output = output.subSequence(i - 1, output.length());
break;
}
}
}
}
return output;
}