How can I convert an external CSS style sheet into the 'style' section of my HTML using Java?
I want to be able to have my external CSS exist in the 'style' section so that I can parse it to inline styles rather than external and the easiest way I have seen to do this is to have the CSS directly in the HTML rather than linked.
I would like to change this in my HTML:
<link rel="stylesheet" href="smartdoc.css" />
To this (Ideally by passing the CSS file as an argument for a method):
<style>
Content from external CSS.
</style>
So that I can apply JSoup to convert it to inline style using something like this:
public static String inlineCss(String html) {
final String style = "style";
Document doc = Jsoup.parse(html);
Elements els = doc.select(style);// to get all the style elements
for (Element e : els) {
String styleRules = e.getAllElements().get(0).data().replaceAll("\n", "").trim();
String delims = "{}";
StringTokenizer st = new StringTokenizer(styleRules, delims);
while (st.countTokens() > 1) {
String selector = st.nextToken(), properties = st.nextToken();
if (!selector.contains(":")) { // skip a:hover rules, etc.
Elements selectedElements = doc.select(selector);
for (Element selElem : selectedElements) {
String oldProperties = selElem.attr(style);
selElem.attr(style,
oldProperties.length() > 0 ? concatenateProperties(
oldProperties, properties) : properties);
}
}
}
e.remove();
}
return doc.toString();
}
private static String concatenateProperties(String oldProp, @NotNull String newProp) {
oldProp = oldProp.trim();
if (!oldProp.endsWith(";"))
oldProp += ";";
return oldProp + newProp.replaceAll("\\s{2,}", " ");
}
Any suggestions for this?
I assume that all your files are on a local hard drive encoded in UTF-8.
dummy.html
<link rel="stylesheet" href="smartdoc.css" />
smartdoc.css
a {
background-color: red;
}
p {
background-color: green;
}
To replace the link
node with the CSS file content, do the following:
// Load HTML file
String charsetName = "UTF-8";
Document doc = Jsoup.parse(new File("dummy.html"), charsetName);
System.out.println("BEFORE:\n" + doc.outerHtml());
// Replace each link nodes with its respective CSS file content
for (Element link : doc.select("link[rel=stylesheet]")) {
String cssFilename = link.attr("href");
Element style = new Element(Tag.valueOf("style"), "");
style.appendText("/* " + cssFilename + " */");
style.appendText(loadCssFileContent(cssFilename, charsetName));
link.replaceWith(style);
}
System.out.println("\nAFTER:\n" + doc.outerHtml());
private static String loadCssFileContent(String path, String charsetName) throws IOException {
byte[] encoded = Files.readAllBytes(Paths.get(path));
return new String(encoded, charsetName);
}
BEFORE:
<html>
<head>
<link rel="stylesheet" href="smartdoc.css">
</head>
<body></body>
</html>
AFTER:
<html>
<head>
<style>/* smartdoc.css */a { background-color: red; } p { background-color: green; }</style>
</head>
<body></body>
</html>