{"id":78335,"date":"2025-07-27T00:29:43","date_gmt":"2025-07-27T00:29:43","guid":{"rendered":"http:\/\/bangla.sitestree.com\/?p=78335"},"modified":"2025-07-27T00:29:43","modified_gmt":"2025-07-27T00:29:43","slug":"java-servletconfig-vs-servletcontext","status":"publish","type":"post","link":"http:\/\/bangla.sitestree.com\/?p=78335","title":{"rendered":"Java: ServletConfig vs ServletContext"},"content":{"rendered":"\n

Here\u2019s a clear and copyright-free comparison of ServletConfig<\/code> vs ServletContext<\/code><\/strong> \u2014 perfect for learning or blogging.<\/p>\n\n\n\n

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\ud83d\udd04 ServletConfig vs ServletContext in Java<\/strong><\/h2>\n\n\n\n

Both ServletConfig<\/code> and ServletContext<\/code> are part of the Java Servlet API<\/strong> and provide access to configuration data, but they serve different scopes and purposes<\/strong>.<\/p>\n\n\n\n

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\ud83d\udccb Comparison Table<\/strong><\/h3>\n\n\n\n
Feature<\/th>ServletConfig<\/code><\/th>ServletContext<\/code><\/th><\/tr><\/thead>
Scope<\/strong><\/td>Per servlet<\/strong><\/td>Per web application<\/strong><\/td><\/tr>
Purpose<\/strong><\/td>Pass init parameters<\/strong> to a specific servlet<\/td>Share data and resources across all servlets<\/strong><\/td><\/tr>
Defined In<\/strong><\/td>Inside <servlet><\/code> tag in web.xml<\/code><\/td>Inside <context-param><\/code> tag in web.xml<\/code><\/td><\/tr>
Accessed By<\/strong><\/td>getServletConfig()<\/code><\/td>getServletContext()<\/code><\/td><\/tr>
Common Use<\/strong><\/td>DB name for one servlet, file path, etc.<\/td>Logging config, app version, global file paths, etc.<\/td><\/tr>
Lifecycle<\/strong><\/td>Exists as long as the servlet is loaded<\/td>Exists as long as the web app is running<\/td><\/tr>
Sharing<\/strong><\/td>Not shared between servlets<\/td>Shared by all servlets in the app<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n
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\ud83e\uddea Example Usage<\/h3>\n\n\n\n

\ud83d\udd39 web.xml<\/code><\/h4>\n\n\n\n
<!-- ServletConfig (specific to one servlet) -->\n<servlet>\n    <servlet-name>MyServlet<\/servlet-name>\n    <servlet-class>com.example.MyServlet<\/servlet-class>\n    <init-param>\n        <param-name>dbName<\/param-name>\n        <param-value>students<\/param-value>\n    <\/init-param>\n<\/servlet>\n\n<!-- ServletContext (shared across servlets) -->\n<context-param>\n    <param-name>appVersion<\/param-name>\n    <param-value>1.2.3<\/param-value>\n<\/context-param>\n<\/code><\/pre>\n\n\n\n
\ud83d\udd39 In Servlet Code<\/h4>\n\n\n\n
public class MyServlet extends HttpServlet {\n\n    public void doGet(HttpServletRequest request, HttpServletResponse response)\n            throws ServletException, IOException {\n        \n        \/\/ ServletConfig example\n        ServletConfig config = getServletConfig();\n        String dbName = config.getInitParameter(\"dbName\");\n\n        \/\/ ServletContext example\n        ServletContext context = getServletContext();\n        String appVersion = context.getInitParameter(\"appVersion\");\n\n        response.getWriter().println(\"DB: \" + dbName + \", App Version: \" + appVersion);\n    }\n}\n<\/code><\/pre>\n\n\n\n
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\u2705 Summary<\/h3>\n\n\n\n