Jsoup is a Java library for working with real-world HTML. It provides a very convenient API for extracting and manipulating data, using the best of DOM, CSS, and jquery-like methods. When dealing with web scraping, handling character encoding correctly is crucial to ensure that the extracted text is not garbled and represents the original content accurately.
Jsoup is quite good at handling character encoding automatically. It will look for a Content-Type header or a <meta charset> tag in the HTML to determine the correct encoding. However, there are times when you might need to handle character encoding issues manually, especially if the server does not specify the encoding or does so incorrectly.
Here's how you can handle character encoding issues with Jsoup:
Specifying the Character Encoding on Parse
If you know the character encoding of the document you are trying to parse, you can specify it directly when using Jsoup's parse methods.
import org.jsoup.Jsoup;
import org.jsoup.nodes.Document;
public class Main {
public static void main(String[] args) {
String html = "<html><head><title>Sample Title</title></head>"
+ "<body><p>Parsed HTML into a doc.</p></body></html>";
Document doc = Jsoup.parse(html, "UTF-8"); // Specify the character encoding
System.out.println(doc.title());
}
}
Fetching a Document from a URL with a Specified Character Encoding
When fetching a document directly from a URL, you can specify the character encoding if it's not correctly detected.
import org.jsoup.Jsoup;
import org.jsoup.nodes.Document;
public class Main {
public static void main(String[] args) {
try {
String url = "http://example.com";
Document doc = Jsoup.connect(url).charset("ISO-8859-1").get(); // Force a specific charset
System.out.println(doc.title());
} catch (IOException e) {
e.printStackTrace();
}
}
}
Dealing with Incorrectly Specified Character Encoding
Sometimes a server might specify an incorrect character encoding in the HTTP headers or in the HTML itself. In such cases, you might need to ignore what is provided and specify the correct one yourself.
import org.jsoup.Jsoup;
import org.jsoup.nodes.Document;
import org.jsoup.nodes.Entities;
public class Main {
public static void main(String[] args) {
try {
String url = "http://example.com";
// Fetch the document without automatically determining the charset
Document doc = Jsoup.connect(url).ignoreContentType(true).execute().parse();
// Now parse the document again with the correct charset
Document correctDoc = Jsoup.parse(new ByteArrayInputStream(doc.toString().getBytes()),
"UTF-8", url);
System.out.println(correctDoc.title());
} catch (IOException e) {
e.printStackTrace();
}
}
}
Setting the Default Character Encoding for Output
When you output a Document to a string or file, you can specify the character encoding to be used for the output.
import org.jsoup.Jsoup;
import org.jsoup.nodes.Document;
public class Main {
public static void main(String[] args) {
Document doc = Jsoup.parse("<div>äöü</div>");
// Set the output encoding to UTF-8
doc.outputSettings().charset("UTF-8");
System.out.println(doc.body().html()); // Outputs with UTF-8 encoding
}
}
Jsoup usually handles encoding correctly, but when dealing with different or incorrectly configured servers, you may need to manually intervene as shown above. Always ensure that you have the legal right to scrape and process the content from the websites you target.
