Error 404 - Get request using @RestController - SpringBoot

Augusto :

Yes, there are lot of questions about it, but each case is unique.

The objective is write a simple application to make CRUD operations on a entity Product, using: Controller, Model and Repository.

Tree:

+- com.teste
  +- controller
  | +- ProductController.java
  +- model
  | +- Product.java
  +- repository
  | +- ProductRepository.java
  +- SpringEsApplication.java

ProductController.java

@RestController
//@RequestMapping(value="/product") // When try it, not works too (same error).
public class ProductController {

@Autowired
private ProductRepository productRepository;

@PostMapping("/saveProduct")
public long saveProduct(@RequestBody List<Product> products) {
    productRepository.saveAll(products);
    return productRepository.count();
}

@GetMapping("/findAllProducts")
public Iterable<Product> findAllProducts() {
    return productRepository.findAll();
}

@GetMapping("/findProductByCode")
public List<Product> findProductByCode(@PathVariable String code) {
    return productRepository.findByCode(code);
}

}

Product.java

@Document(indexName = "product_index")
@Data
@AllArgsConstructor
@NoArgsConstructor
public class Product {

    @Id
    private String id;
    private String name;
    private String code;
    private double price;

}

ProductRepository.java

@Repository
public interface ProductRepository extends CrudRepository<Product,String> {

    List<Product> findByCode(String code);

}

SpringEsApplication.java

@SpringBootApplication
@ComponentScan(basePackages = {"com.teste.repository"})
public class SpringEsApplication {

    public static void main(String[] args) {
        SpringApplication.run(SpringEsApplication.class, args);
    }

}

Postman GET Request

GET Request:

http://localhost:8080/findAllProducts

Response:

{
    "timestamp": "2019-09-18T14:10:38.305+0000",
    "status": 404,
    "error": "Not Found",
    "message": "No message available",
    "path": "/findAllProducts"
}

Even without data, it should return something.

Console log starting

 :: Spring Boot ::        (v2.1.8.RELEASE)

2019-09-18 11:16:34.061  INFO 4764 --- [  restartedMain] com.teste.SpringEsApplication            : Starting SpringEsApplication on CTDDELL5JVV862 with PID 4764 (started by augusto.cadini in C:\Users\augusto.cadini\Desktop\Spring ElasticSearch projects\spring-es)
2019-09-18 11:16:34.069  INFO 4764 --- [  restartedMain] com.teste.SpringEsApplication            : No active profile set, falling back to default profiles: default
2019-09-18 11:16:34.193  INFO 4764 --- [  restartedMain] .e.DevToolsPropertyDefaultsPostProcessor : Devtools property defaults active! Set 'spring.devtools.add-properties' to 'false' to disable
2019-09-18 11:16:34.193  INFO 4764 --- [  restartedMain] .e.DevToolsPropertyDefaultsPostProcessor : For additional web related logging consider setting the 'logging.level.web' property to 'DEBUG'
2019-09-18 11:16:34.774  INFO 4764 --- [  restartedMain] .s.d.r.c.RepositoryConfigurationDelegate : Bootstrapping Spring Data repositories in DEFAULT mode.
2019-09-18 11:16:34.829  INFO 4764 --- [  restartedMain] .s.d.r.c.RepositoryConfigurationDelegate : Finished Spring Data repository scanning in 51ms. Found 2 repository interfaces.
2019-09-18 11:16:35.516  INFO 4764 --- [  restartedMain] o.s.b.w.embedded.tomcat.TomcatWebServer  : Tomcat initialized with port(s): 8080 (http)
2019-09-18 11:16:35.544  INFO 4764 --- [  restartedMain] o.apache.catalina.core.StandardService   : Starting service [Tomcat]
2019-09-18 11:16:35.544  INFO 4764 --- [  restartedMain] org.apache.catalina.core.StandardEngine  : Starting Servlet engine: [Apache Tomcat/9.0.24]
2019-09-18 11:16:35.671  INFO 4764 --- [  restartedMain] o.a.c.c.C.[Tomcat].[localhost].[/]       : Initializing Spring embedded WebApplicationContext
2019-09-18 11:16:35.672  INFO 4764 --- [  restartedMain] o.s.web.context.ContextLoader            : Root WebApplicationContext: initialization completed in 1479 ms
2019-09-18 11:16:35.949  INFO 4764 --- [  restartedMain] o.elasticsearch.plugins.PluginsService   : no modules loaded
2019-09-18 11:16:35.950  INFO 4764 --- [  restartedMain] o.elasticsearch.plugins.PluginsService   : loaded plugin [org.elasticsearch.index.reindex.ReindexPlugin]
2019-09-18 11:16:35.950  INFO 4764 --- [  restartedMain] o.elasticsearch.plugins.PluginsService   : loaded plugin [org.elasticsearch.join.ParentJoinPlugin]
2019-09-18 11:16:35.950  INFO 4764 --- [  restartedMain] o.elasticsearch.plugins.PluginsService   : loaded plugin [org.elasticsearch.percolator.PercolatorPlugin]
2019-09-18 11:16:35.950  INFO 4764 --- [  restartedMain] o.elasticsearch.plugins.PluginsService   : loaded plugin [org.elasticsearch.script.mustache.MustachePlugin]
2019-09-18 11:16:35.950  INFO 4764 --- [  restartedMain] o.elasticsearch.plugins.PluginsService   : loaded plugin [org.elasticsearch.transport.Netty4Plugin]
2019-09-18 11:16:36.901  INFO 4764 --- [  restartedMain] o.s.d.e.c.TransportClientFactoryBean     : Adding transport node : 192.168.99.100:9300
2019-09-18 11:16:37.260  INFO 4764 --- [  restartedMain] o.s.b.d.a.OptionalLiveReloadServer       : LiveReload server is running on port 35729
2019-09-18 11:16:37.572  INFO 4764 --- [  restartedMain] o.s.s.concurrent.ThreadPoolTaskExecutor  : Initializing ExecutorService 'applicationTaskExecutor'
2019-09-18 11:16:37.956  INFO 4764 --- [  restartedMain] o.s.b.w.embedded.tomcat.TomcatWebServer  : Tomcat started on port(s): 8080 (http) with context path ''
2019-09-18 11:16:37.957  INFO 4764 --- [  restartedMain] com.teste.SpringEsApplication            : Started SpringEsApplication in 4.838 seconds (JVM running for 5.522)

Yogesh Prajapati :

Remove @ComponentScan(basePackages = {"com.teste.repository"}) from you main class.

It is not required in your case.

When you provide @ComponentScan, Spring engine will scan those packages only which you have provided.

@ComponentScan is required to provide custom scanning of packages/classes.