Why Does My Java Program Get a 403 Forbidden Error from Google Search While My Browser Doesn't?

403 Forbidden Encountered with Java but Not Web Browsers

When attempting to retrieve the number of results for a Google search term using a Java program, developers may encounter a 403 Forbidden error while web browsers provide the correct results. This discrepancy arises from the lack of a user agent header in the Java program.

Solution:

To resolve the issue, it is necessary to set the user agent header in the Java program. Implement the following code snippet:

URLConnection connection = new URL("https://www.google.com/search?q=" + query).openConnection();
connection.setRequestProperty("User-Agent", "Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.11 (KHTML, like Gecko) Chrome/23.0.1271.95 Safari/537.11");
connection.connect();

BufferedReader r = new BufferedReader(new InputStreamReader(connection.getInputStream(), Charset.forName("UTF-8")));

...

Note:

1. SSL Handling: SSL is handled transparently, as seen in the exception stacktrace.
2. Result Amount Retrieval: Obtaining the exact result amount requires additional steps, including fetching cookies and parsing redirect tokens.
3. Example Code: The provided code demonstrates the complete process, resulting in the correct number of results.

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