标签：#Spring

Hi HN, I built an open-source Java SDK for building Model Context Protocol servers: https://github.com/6000fish/mcp-java It is intended for Java developers who want to expose tools, resources, or prompts to MCP-compatible agents without implementing the protocol plumbing from scratch. The project includes: Core MCP server SDK stdio transport SSE transport Java API and annotation-based tool registration Spring Boot starter 5-minute quick-start example Copyable custom server template Ready-to-use MySQL and Redis MCP servers The SDK is available on Maven Central: <dependency> <groupId> io.github.6000fish </groupId> <artifactId> mcp-sdk </artifactId> <version> 0.1.1 </version> </dependency> <dependency> <groupId> io.github.6000fish </groupId> <artifactId> mcp-spring-boot-starter </artifactId> <version> 0.1.1 </version> </dependency> The MySQL and Redis servers are local stdio MCP servers, because database/cache connectors are usually safer to run inside the user's own environment instead of exposing credentials to a hosted remote endpoint. GitHub: https://github.com/6000fish/mcp-java Release: https://github.com/6000fish/mcp-java/releases/tag/v0.1.1 Feedback is welcome.

Why I built this Every time I started a new Java full stack project I was spending 2-3 days just on setup — JWT configuration, Spring Security, CORS, connecting Angular to backend. So I decided to build a reusable starter kit once and never do that setup again. What I built A complete full stack starter kit with: Spring Boot 3.5 REST API Angular 19 frontend connected to backend MySQL database with User table ready JWT Authentication working out of the box Spring Security configured Full CRUD operations Clean layered architecture (Controller → Service → Repository) The Tech Stack Backend: Java 17, Spring Boot, Spring Security, JWT, JPA Frontend: Angular 19, TypeScript Database: MySQL How it works User registers via POST /api/users User logs in via POST /api/auth/login Backend returns JWT token Frontend stores token in localStorage All protected routes require valid token Invalid or missing token returns 401 Unauthorized What I learned JWT configuration in Spring Security is confusing at first CORS needs to be configured in SecurityConfig not just main class Angular HttpClient needs provideHttpClient() in app.config.ts Service layer keeps code clean and testable GitHub Full source code is available here: https://github.com/shindebuilds/springboot-angular-starter-kit Feel free to clone it, use it, improve it. If you want the packaged version with setup instructions: https://hanumant4.gumroad.com/l/caopgu Happy building!

Static Application Security Testing (SAST) is a critical practice in modern DevSecOps. While tools like SonarQube, Snyk, and Veracode are popular, this article focuses on GitHub CodeQL – a semantic code analysis engine that treats code as a database. We will apply it to a vulnerable Java Spring Boot application to detect SQL Injection and Path Traversal. 🤔 Why CodeQL? Unlike pattern-based scanners, CodeQL builds a relational database of your code, including abstract syntax trees, control flow graphs, and data flow graphs. This allows it to track tainted data across functions, classes, and files, drastically reducing false positives. 🚨 Target Application (Vulnerable Java App) Let's look at a simple REST API with two vulnerable endpoints. File: UserController.java package com.demo.controller ; import com.demo.model.User ; import org.springframework.beans.factory.annotation.Autowired ; import org.springframework.jdbc.core.JdbcTemplate ; import org.springframework.web.bind.annotation.* ; import java.nio.file.Files ; import java.nio.file.Paths ; import java.util.List ; @RestController @RequestMapping ( "/api" ) public class UserController { @Autowired private JdbcTemplate jdbcTemplate ; // Vulnerability 1: SQL Injection @GetMapping ( "/users" ) public List < User > getUsers ( @RequestParam ( "id" ) String userId ) { String sql = "SELECT * FROM users WHERE id = " + userId ; // Dangerous concatenation return jdbcTemplate . query ( sql , ( rs , rowNum ) -> new User ( rs . getString ( "id" ), rs . getString ( "name" ))); } // Vulnerability 2: Path Traversal @GetMapping ( "/file" ) public String readFile ( @RequestParam ( "filename" ) String filename ) throws Exception { return new String ( Files . readAllBytes ( Paths . get ( "/var/data/" + filename ))); } } 🛠️ Installing and Configuring CodeQL CLI You can run CodeQL locally to analyze your code before pushing it to a repository. 1. Download CodeQL from GitHub releases: wget [ https://github.com/github/codeql-cli-binaries/re

RestTemplate is a synchronous Spring Framework client used to consume RESTful web services by simplifying HTTP communication. Synchronous Communication: It blocks the execution thread until a response is received.HTTP Methods: It provides built-in methods for standard operations like GET, POST, PUT, and DELETE.Automatic Mapping: It can automatically convert JSON or XML responses into Java domain objects using message converters.Status: While widely used, it is in maintenance mode. For new projects, Spring recommends using the modern RestClient or the reactive. Its an automate work. getForObject() Performs a GET request and returns the response body directly as an object. getForEntity() Performs a GET request and returns a ResponseEntity (includes status and headers). postForObject() Sends data via POST and returns the mapped response body. exchange() A general-purpose method for all HTTP verbs, offering full control over headers and request entities. getForObject- Controller Snippet Response is received in Object format. @RestController @RequestMapping("/api") public class ApiController { @Autowired private ApiService apiService; @GetMapping("/getUsers") public String users() { return apiService.getUsers(); } Service snippet: @Service public class ApiService { @Autowired private RestTemplate restTemplate; @Autowired UserApiRepo userApiRepo; public String getUsers() { String url = "https://jsonplaceholder.typicode.com/users"; String response = restTemplate.getForObject(url, String.class); return response; } Response: "id": 1, "name": "Leanne Graham", "username": "Bret", "email": "Sincere@april.biz", "address": { "street": "Kulas Light", "suite": "Apt. 556", "city": "Gwenborough", "zipcode": "92998-3874", "geo": { "lat": "-37.3159", "lng": "81.1496" } }, "phone": "1-770-736-8031 x56442", "website": "hildegard.org", "company": { "name": "Romaguera-Crona", "catchPhrase": "Multi-layered client-server neural-net", "bs": "harness real-time e-markets" } getForEntity() Respo