--- title: Modernize Java with Cursor and GitLab | daily.dev description: A step-by-step tutorial demonstrating how to use Cursor AI coding agent alongside GitLab to incrementally modernize a Java 8 codebase to Java 21. The workflow... canonical: https://daily.dev/posts/modernize-java-with-cursor-and-gitlab-cwlnq3yep twitter:card: summary_large_image twitter:site: @dailydotdev og:type: website og:site_name: daily.dev og:title: Modernize Java with Cursor and GitLab | daily.dev og:description: A step-by-step tutorial demonstrating how to use Cursor AI coding agent alongside GitLab to incrementally modernize a Java 8 codebase to Java 21. The workflow... og:url: https://daily.dev/posts/modernize-java-with-cursor-and-gitlab-cwlnq3yep og:image: https://api.daily.dev/og/posts/CwLNQ3YEP.png og:image:alt: Modernize Java with Cursor and GitLab og:image:width: 1200 og:image:height: 630 og:locale: en --- > ## Documentation Index > Fetch the complete documentation index at: https://daily.dev/llms.txt > Use this file to discover all available pages before exploring further. # Modernize Java with Cursor and GitLab **[GitLab](https://daily.dev/sources/gitlab)** · 19 min read · 4 upvotes · 0 comments ## Summary A step-by-step tutorial demonstrating how to use Cursor AI coding agent alongside GitLab to incrementally modernize a Java 8 codebase to Java 21. The workflow covers three use cases: fixing a failing end-to-end test, setting up CI/CD quality gates using GitLab MCP for project context, and replacing the legacy HttpURLConnection API with Java 21's HttpClient. GitLab's Duo Agent Platform, MCP server, Code Review Flow, and CI/CD pipelines provide the safety guardrails that keep each agent-driven change scoped, reviewed, and traceable. Tips on AGENTS.md, review instructions, and reusable agentic skills are also included. ## Full article daily.dev links to this article rather than hosting it. Read it at the original source: ## Questions this post answers ### What is the recommended way to replace HttpURLConnection with HttpClient when modernizing Java 8 code to Java 21? Replace HttpURLConnection with a single reusable java.net.http.HttpClient instance in one bounded change, without adding virtual threads, changing the time model, or upgrading unrelated dependencies at the same time. Because redirects, restricted headers, timeout scope, response bodies, interruption, and connection reuse behave differently between the two APIs, cover the change with focused local HTTP server tests plus a Docker Compose functional test verifying downstream ingestion still works. _Developers planning a Java 8 to 21 HTTP migration can follow similar scoped workflows shared on daily.dev._ ### How can I use an MCP server to give a coding agent like Cursor context from GitLab issues and epics during a large migration? Connect Cursor to GitLab's MCP server over HTTP transport by adding a mcpServers entry pointing to https:///api/v4/mcp in mcp.json, replacing the placeholder with gitlab.com or a self-managed instance URL. Once authenticated, Cursor accesses only the projects and resources the user's GitLab identity already permits, and can pull in epics, work items, pipeline history, and dependencies, plus use tools like create_workitem_note to log progress. _Teams wiring AI agents into their GitLab workflow track setup guides like this through daily.dev._ ## Similar posts on daily.dev - [Best practices for coding with agents · Cursor](https://daily.dev/posts/best-practices-for-coding-with-agents-cursor-cxrvbsqka) · Cursor · 27 upvotes · 0 comments - [How to Use Cursor with Modern Angular](https://daily.dev/posts/how-to-use-cursor-with-modern-angular-lj5he1gz6) · Telerik · 0 upvotes · 0 comments - [Cursor 3: A much simpler, more powerful, agent-friendly Code Editor](https://daily.dev/posts/cursor-3-a-much-simpler-more-powerful-agent-friendly-code-editor-js459cezu) · Product Hunt · 3 upvotes · 0 comments --- Tags: [#java](https://daily.dev/tags/java), [#cicd](https://daily.dev/tags/cicd), [#mcp](https://daily.dev/tags/mcp), [#gitlab](https://daily.dev/tags/gitlab) [View this post on daily.dev](https://daily.dev/posts/modernize-java-with-cursor-and-gitlab-cwlnq3yep) ```json {"@context":"https://schema.org","@graph":[{"@type":"Organization","@id":"https://daily.dev/#organization","name":"daily.dev","url":"https://daily.dev","logo":{"@type":"ImageObject","url":"https://daily.dev/apple-touch-icon.png","width":180,"height":180},"sameAs":["https://twitter.com/dailydotdev","https://github.com/dailydotdev","https://www.linkedin.com/company/daily-dev-ltd"]},{"@type":"WebSite","@id":"https://daily.dev/#website","url":"https://daily.dev","name":"daily.dev","publisher":{"@id":"https://daily.dev/#organization"},"potentialAction":{"@type":"SearchAction","target":{"@type":"EntryPoint","urlTemplate":"https://daily.dev/search?q={search_term_string}"},"query-input":"required name=search_term_string"}}]} {"@context":"https://schema.org","@type":"TechArticle","headline":"Modernize Java with Cursor and GitLab","url":"https://daily.dev/posts/modernize-java-with-cursor-and-gitlab-cwlnq3yep","mainEntityOfPage":{"@type":"WebPage","@id":"https://daily.dev/posts/modernize-java-with-cursor-and-gitlab-cwlnq3yep"},"datePublished":"2026-07-22T18:27:43.526Z","dateModified":"2026-09-14T09:16:15.778Z","description":"A step-by-step tutorial demonstrating how to use Cursor AI coding agent alongside GitLab to incrementally modernize a Java 8 codebase to Java 21. 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