How can I get client information such as OS and browser

Question

Your best bet is User-Agent header. You can get it like this in JSP or Servlet,

String userAgent = request.getHeader("User-Agent");

The header looks like this,

User-Agent: Mozilla/5.0 (Macintosh; U; Intel Mac OS X 10.5; en-US; rv:1.9.0.13) Gecko/2009073021 Firefox/3.0.13

It provides detailed information on browser. However, it's pretty much free format so it's very hard to decipher every single one. You just need to figure out which browsers you will support and write parser for each one. When you try to identify the version of browser, always check newer version first. For example, IE6 user-agent may contain IE5 for backward compatibility. If you check IE5 first, IE6 will be categorized as IE5 also.

You can get a full list of all user-agent values from this web site,

http://www.user-agents.org/

With User-Agent, you can tell the exact version of the browser. You can get a pretty good idea on OS but you may not be able to distinguish between different versions of the same OS, for example, Windows NT and 2000 may use same User-Agent.

There is nothing about resolution. However, you can get this with Javascript on an AJAX call.

In Java there is no direct way to get browser and OS related information.

But to get this few third-party tools are available.

Instead of trusting third-party tools, I suggest you to parse the user agent.

String  browserDetails  =   request.getHeader("User-Agent");

By doing this you can separate the browser details and OS related information easily according to your requirement. PFB the snippet for reference (you can replace this with a switch case as well).

        String  browserDetails  =   request.getHeader("User-Agent");
        String  userAgent       =   browserDetails;
        String  user            =   userAgent.toLowerCase();
    
        String os = "";
        String browser = "";

        log.info("User Agent for the request is===>"+browserDetails);
        //=================OS=======================
         if (userAgent.toLowerCase().indexOf("windows") >= 0 )
         {
             os = "Windows";
         } else if(userAgent.toLowerCase().indexOf("mac") >= 0)
         {
             os = "Mac";
         } else if(userAgent.toLowerCase().indexOf("x11") >= 0)
         {
             os = "Unix";
         } else if(userAgent.toLowerCase().indexOf("android") >= 0)
         {
             os = "Android";
         } else if(userAgent.toLowerCase().indexOf("iphone") >= 0)
         {
             os = "IPhone";
         }else{
             os = "UnKnown, More-Info: "+userAgent;
         }
         //===============Browser===========================
        if (user.contains("msie"))
        {
            String substring=userAgent.substring(userAgent.indexOf("MSIE")).split(";")[0];
            browser=substring.split(" ")[0].replace("MSIE", "IE")+"-"+substring.split(" ")[1];
        } else if (user.contains("safari") && user.contains("version"))
        {
            browser=(userAgent.substring(userAgent.indexOf("Safari")).split(" ")[0]).split("/")[0]+"-"+(userAgent.substring(userAgent.indexOf("Version")).split(" ")[0]).split("/")[1];
        } else if ( user.contains("opr") || user.contains("opera"))
        {
            if(user.contains("opera"))
                browser=(userAgent.substring(userAgent.indexOf("Opera")).split(" ")[0]).split("/")[0]+"-"+(userAgent.substring(userAgent.indexOf("Version")).split(" ")[0]).split("/")[1];
            else if(user.contains("opr"))
                browser=((userAgent.substring(userAgent.indexOf("OPR")).split(" ")[0]).replace("/", "-")).replace("OPR", "Opera");
        } else if (user.contains("chrome"))
        {
            browser=(userAgent.substring(userAgent.indexOf("Chrome")).split(" ")[0]).replace("/", "-");
        } else if ((user.indexOf("mozilla/7.0") > -1) || (user.indexOf("netscape6") != -1)  || (user.indexOf("mozilla/4.7") != -1) || (user.indexOf("mozilla/4.78") != -1) || (user.indexOf("mozilla/4.08") != -1) || (user.indexOf("mozilla/3") != -1) )
        {
            //browser=(userAgent.substring(userAgent.indexOf("MSIE")).split(" ")[0]).replace("/", "-");
            browser = "Netscape-?";
                  
        } else if (user.contains("firefox"))
        {
            browser=(userAgent.substring(userAgent.indexOf("Firefox")).split(" ")[0]).replace("/", "-");
        } else if(user.contains("rv"))
        {
            browser="IE-" + user.substring(user.indexOf("rv") + 3, user.indexOf(")"));
        } else
        {
            browser = "UnKnown, More-Info: "+userAgent;
        }
        log.info("Operating System======>"+os);
        log.info("Browser Name==========>"+browser);
        
    

Update: The project is EOL and not maintained anymore. He recommends switching to the Browscap project.

You can use the bitwalker useragentutils library: https://github.com/HaraldWalker/user-agent-utils. It will provide you information about the Browser (name, type, version, manufacturer, etc.) and about the OperatingSystem. A good thing about it is that it is maintained. Access the link that I have provided to see the Maven dependency that you need to add to you project in order to use it.

See below sample code that returns the browser name and browser version.

    UserAgent userAgent = UserAgent.parseUserAgentString(request.getHeader("User-Agent"));
    Browser browser = userAgent.getBrowser();

    String browserName = browser.getName();
    //or 
    // String browserName = browser.getGroup().getName();
    Version browserVersion = userAgent.getBrowserVersion();
    System.out.println("The user is using browser " + browserName + " - version " + browserVersion);

The browser sends this information in the HTTP header. See the snoop example of Tomcat for some code (source, online demo).

Note that this information is not reliable. Browser can and do lie about who they are and what OS they run on.

There are two not bad libs for parsing user agent strings:

• user-agent-utils - java only, reached end-of-life
• ua-parser - multilanguage, archived
• uap-java - java implementation of above, actively maintained

You can use browscap-java to get browser's information.

For Example:

UserAgentParser parser = new UserAgentService().loadParser(Arrays.asList(BrowsCapField.BROWSER));
    Capabilities capabilities = parser.parse(user_agent);

    String browser = capabilities.getBrowser();

Here's my code that works, as of today, with some of the latest browsers.

Naturally, it will break as User-Agent's evolve, but it's simple, and easy to fix.

    String userAgent = "Unknown";
    String osType = "Unknown";
    String osVersion = "Unknown";
    String browserType = "Unknown";
    String browserVersion = "Unknown";
    String deviceType = "Unknown";

    try {
        userAgent = "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/73.0.3683.103 Safari/537.36 OPR/60.0.3255.165";
        //userAgent = "Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:68.0) Gecko/20100101 Firefox/68.0";
        //userAgent = "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/76.0.3809.100 Safari/537.36";
        //userAgent = "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/64.0.3282.140 Safari/537.36 Edge/17.17134";
        //userAgent = "Mozilla/5.0 (iPhone; CPU iPhone OS 12_3_1 like Mac OS X) AppleWebKit/605.1.15 (KHTML, like Gecko) Version/12.1.1 Mobile/15E148 Safari/604.1";
        boolean exceptionTest = false;
        if(exceptionTest) throw new Exception("EXCEPTION TEST");

        if (userAgent.indexOf("Windows NT") >= 0) {
            osType = "Windows";
            osVersion = userAgent.substring(userAgent.indexOf("Windows NT ")+11, userAgent.indexOf(";"));

        } else if (userAgent.indexOf("Mac OS") >= 0) {
            osType = "Mac";
            osVersion = userAgent.substring(userAgent.indexOf("Mac OS ")+7, userAgent.indexOf(")"));

            if(userAgent.indexOf("iPhone") >= 0) {
                deviceType = "iPhone";
            } else if(userAgent.indexOf("iPad") >= 0) {
                deviceType = "iPad";
            }

        } else if (userAgent.indexOf("X11") >= 0) {
            osType = "Unix";
            osVersion = "Unknown";

        } else if (userAgent.indexOf("android") >= 0) {
            osType = "Android";
            osVersion = "Unknown";
        }
        logger.trace("end of os section");

        if (userAgent.contains("Edge/")) {
            browserType = "Edge";
            browserVersion = userAgent.substring(userAgent.indexOf("Edge")).split("/")[1];

        } else if (userAgent.contains("Safari/") && userAgent.contains("Version/")) {
            browserType = "Safari";
            browserVersion = userAgent.substring(userAgent.indexOf("Version/")+8).split(" ")[0];

        } else if (userAgent.contains("OPR/") || userAgent.contains("Opera/")) {
            browserType = "Opera";
            browserVersion = userAgent.substring(userAgent.indexOf("OPR")).split("/")[1];

        } else if (userAgent.contains("Chrome/")) {
            browserType = "Chrome"; 
            browserVersion = userAgent.substring(userAgent.indexOf("Chrome")).split("/")[1];
            browserVersion = browserVersion.split(" ")[0];

        } else if (userAgent.contains("Firefox/")) {
            browserType = "Firefox"; 
            browserVersion = userAgent.substring(userAgent.indexOf("Firefox")).split("/")[1];
        }            
        logger.trace("end of browser section");

    } catch (Exception ex) {
        logger.error("ERROR: " +ex);            
    }

    logger.debug(
              "\n userAgent: " + userAgent
            + "\n osType: " + osType
            + "\n osVersion: " + osVersion
            + "\n browserType: " + browserType
            + "\n browserVersion: " + browserVersion
            + "\n deviceType: " + deviceType
            );

Logger Output:

 userAgent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/73.0.3683.103 Safari/537.36 OPR/60.0.3255.165
 osType: Windows
 osVersion: 10.0
 browserType: Opera
 browserVersion: 60.0.3255.165
 deviceType: Unknown