Simple spring boot application not works - java

I have created very simple spring boot application. But it dose not return the expected output. I have mentioned tried code below.
Main:
package com.example.practice;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
#SpringBootApplication
public class DemoApplication {
public static void main(String[] args) {
SpringApplication.run(DemoApplication.class, args);
}
}
Controller:
package com.example.controller;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;
#RestController
#RequestMapping("/api")
public class ControllerClass {
#GetMapping("/all")
public String getAllUsers() {
return "get All users";
}
}
Properties:
server.port=8090
pom.xml
<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>2.3.5.RELEASE</version>
<relativePath/> <!-- lookup parent from repository -->
</parent>
<groupId>com.practice</groupId>
<artifactId>practice</artifactId>
<version>0.0.1-SNAPSHOT</version>
<name>demo</name>
<description>Practice project for Spring Boot</description>
<properties>
<java.version>1.8</java.version>
</properties>
<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-devtools</artifactId>
<scope>runtime</scope>
<optional>true</optional>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-test</artifactId>
<scope>test</scope>
<exclusions>
<exclusion>
<groupId>org.junit.vintage</groupId>
<artifactId>junit-vintage-engine</artifactId>
</exclusion>
</exclusions>
</dependency>
</dependencies>
<build>
<plugins>
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
</plugin>
</plugins>
</build>
</project>
I tried in my browser by using this endpoint: http://localhost:8090/api/all
expected output:
get All users
current output:
Whitelabel Error Page
This application has no explicit mapping for /error, so you are seeing this as a fallback.
Sun Nov 01 00:44:41 IST 2020
There was an unexpected error (type=Not Found, status=404).
No message available
What is the wrong I have done in my code. I am new to spring boot. Please help me to solve this problem. Thank you.

This can be the problem with packages of classes.
Make sure your ControllerClass is in the subpackage of DemoApplication (for example, DemoApplication is in org.example package and controller is in org.example.controllers package) or use #SpringBootApplication(scanBasePackages = "package.with.your.controller")
The problem is, the #SpringBootApplication annotation consists of:
#Configuration
#EnableAutoConfiguration
#ComponentScan
#ComponentScan here is without arguments, so according to docs, scanning will occur from the package of the class that declares this annotation. It will scan com.example.practice and subpackages, but not com.example.controllers.

Try to use this
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;
#RestController
#RequestMapping("/api")
public class ControllerClass {
#GetMapping("/all")
public ResponseEntity<String> getAllUsers() {
return new ResponseEntity<>("get All users",HttpStatus.OK);
}
}
Upd. It looks that you have also different packages
package com.example.practice;
package com.example.controller;
and #SpringBootApplication can't autoscan your beans. There are two ways to resolve it:
Move DemoApplication class to next path com.example this necessary for spring boot to autoscan beans in packages below.
You need to add additional annotation #ComponentScan(“com.example”) to your DemoApplication

Related

Whitelabel page error for graphql mapping

I'm new to spring boot and trying to learn how to implement graphql. #GetMapping and #PostMapping work as normal but when I try to use #QueryMapping or #SchemaMapping, following the Spring documentation I get the whitelabel error page. Playing around I'm able to guess that it's not recognizing these two as mapping. I've checked my dependencies but I'll include them below in case, I've verified the project structure, and I've also tried changing from #Controller to #RestController to no avail.
Controller file
package com.example.GraphQLBooks.controller;
import com.example.GraphQLBooks.model.Book;
import com.example.GraphQLBooks.repository.BookRepository;
import org.springframework.graphql.data.method.annotation.QueryMapping;
import org.springframework.graphql.data.method.annotation.SchemaMapping;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.RestController;
import java.util.List;
#RestController
public class BookController {
private final BookRepository bookRepository;
public BookController(BookRepository bookRepository) {
this.bookRepository = bookRepository;
}
//This works with #RestController but breaks with #Controller
#GetMapping("/test")
public String controllerTest(){
return "Hello";
}
//#SchemaMapping(typeName = "Query",value = "allBooks")
#QueryMapping
public List<Book> findAll() {
return bookRepository.findAll();
}
}
pom.xml
<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>2.7.2</version>
<relativePath/> <!-- lookup parent from repository -->
</parent>
<groupId>com.example</groupId>
<artifactId>GraphQL-Books</artifactId>
<version>0.0.1-SNAPSHOT</version>
<name>GraphQL-Books</name>
<description>Demo project for Spring Boot</description>
<properties>
<java.version>17</java.version>
</properties>
<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-graphql</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-test</artifactId>
<scope>test</scope>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-webflux</artifactId>
<scope>test</scope>
</dependency>
<dependency>
<groupId>org.springframework.graphql</groupId>
<artifactId>spring-graphql-test</artifactId>
<scope>test</scope>
</dependency>
<dependency>
<groupId>com.graphql-java</groupId>
<artifactId>graphql-java</artifactId>
</dependency>
</dependencies>
<build>
<plugins>
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
</plugin>
</plugins>
</build>
</project>
application.properties
spring.graphql.graphiql.enabled=true
I tested the repositories using #GetMapping and they output as expected and when I got to my "/test" mapping it outputs Hello as expected. Any insight and tips are appreciated, and let me know if more info is needed.
Figured it out. My schema had a typo had schema.graphql instead of schema.graphqls and it should be localhost:8080/graphiql not localhost:8080/graphql dumb mistakes I know. And you can't use #RestController with graphql has to be #Controller which makes sense because we're not using a Rest Api.
Had similar issue. The problem was graphqls file wasn't placed in the right folder.
Spring boot graphQL looks for the graphqls file in the following directory by default: ~/src/main/resources/graphql/schema.graphqls

Getting error "Whitelabel Error Page" while running localhost:8080

I started learning Spring Framework and get this kind of error while running localhost:8080
Whitelabel Error Page
This application has no explicit mapping for /error, so you are seeing this as a fallback.
Controller.java
package com.springFramework.helloGame.controller;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RestController;
#RestController
public class Controller {
#GetMapping("/sum")
public long displaySum(){
return 100;
}
}
HelloGameApplication.java
package com.springFramework.helloGame;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.context.ConfigurableApplicationContext;
import org.springframework.context.annotation.ComponentScan;
#SpringBootApplication
public class HelloGameApplication {
public static void main(String[] args) {
ConfigurableApplicationContext context =
SpringApplication.run(HelloGameApplication.class, args);
}
}
pom.xml
<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>2.5.4</version>
<relativePath/> <!-- lookup parent from repository -->
</parent>
<groupId>com.springFramework</groupId>
<artifactId>helloGame</artifactId>
<version>0.0.1-SNAPSHOT</version>
<name>helloGame</name>
<description>Demo project for Spring Boot</description>
<properties>
<java.version>11</java.version>
</properties>
<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-test</artifactId>
<scope>test</scope>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
</dependencies>
<build>
<plugins>
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
</plugin>
</plugins>
</build>
</project>
my project structure looks fine, but don't know why I got error!
Please help me!
The Whitelabel page is a spring error handling method and it tries to hint to you that you do have a mapping for /error.
Now coming to the issue you need to write #RequestMapping("/") above your get mapping in the controller so that the spring knows the base URI.
It's an entry point for the spring application for the browser.
Now you have written /sum get URI and in the browser, you are trying for http://localhost:8080
So for the above Uri to work you need to provide #RequestMapping("/")
or you can use http://localhost:8080/sum with you current code.
It seems your controller only have a mapping for "/sum" path. Try querying localhost:8080/sum.

Whitelabel Error Page, rest urls not executed in springboot

new to spring boot application development. I ran the application as java application and got the below error. THe application is deployed successfully , I don't know why this error is rendered ... beating my head.. thank you for your help in advance.
Whitelabel Error Page This application has no explicit mapping for
/error, so you are seeing this as a fallback. Sat Jul 13 21:37:31 IST
2019 There was an unexpected error (type=Not Found, status=404). No
message available
tried solutions given on stack overflow but no help. could you please help me if anywhere I do wrong here.
package com.cpi.poc.controller;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.context.annotation.ComponentScan;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;
import com.cpi.poc.service.IService;
#RestController
#RequestMapping(value ="/test")
#ComponentScan(basePackages = "com.cgi.poc")
public class TestController {
#Autowired
IService service;
#RequestMapping(value = "/greet" , method = RequestMethod.GET)
public String testService(){
String result = service.greet();
return result;
}
}
pom.xml
<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>1.5.21.RELEASE</version>
<relativePath/> <!-- lookup parent from repository -->
</parent>
<groupId>com.cgi.poc</groupId>
<artifactId>test</artifactId>
<version>0.0.1-SNAPSHOT</version>
<name>test</name>
<description>Demo project for Spring Boot</description>
<properties>
<java.version>1.8</java.version>
</properties>
<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-tomcat</artifactId>
<scope>provided</scope>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-test</artifactId>
<scope>test</scope>
</dependency>
</dependencies>
<build>
<plugins>
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
</plugin>
</plugins>
</build>
Check whether you have class :
#SpringBootApplication
#ComponentScan("com.cgi.poc")
#ComponentScan
public class Application {
public static void main(String[] args) {
SpringApplication.run(Application.class, args);
}
}
No need to put component scan on controller if you have the above class.
Verify by using lsof command that your java service is running on the port on not.

Spring boot Field required a bean of type that could not be found

I'm going through the JPA starter tutorial for spring boot am struggling.
I know the question has been asked sometimes here ('Field required a bean of type that could not be found.' error spring restful API using mongodb)
But those problems are a bit different from what I have.
Structure
java
|
helloWorld
|
web/ -- HelloWorldController
Application
Customer
CustomerRepository
ServletInitializer
As you can see all my packages related to JPA are on the same level as my Application file . According to the tutorial (https://spring.io/guides/gs/accessing-data-jpa/) this should work
My Application class
package helloWorld;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.boot.builder.SpringApplicationBuilder;
import org.springframework.boot.web.servlet.support.SpringBootServletInitializer;
import org.springframework.context.annotation.ComponentScan;
#SpringBootApplication
public class Application extends SpringBootServletInitializer {
public static void main(String[] args) {
SpringApplication.run(Application.class, args);
}
#Autowired
CustomerRepository customerRepository;
#Override
protected SpringApplicationBuilder configure(SpringApplicationBuilder application) {
return application.sources(Application.class);
}
}
CustomerRepository
package helloWorld;
import org.springframework.data.repository.CrudRepository;
import java.util.List;
public interface CustomerRepository extends CrudRepository<Customer, Long> {
List<Customer> findByLastName(String lastName);
}
When trying to use #Autowired I receive
***************************
APPLICATION FAILED TO START
***************************
Description:
Field customerRepository in helloWorld.Application required a bean of type 'helloWorld.CustomerRepository' that could not be found.
Action:
Consider defining a bean of type 'helloWorld.CustomerRepository' in your configuration.
Also, adding scanBasePackages={"helloWorld"}) to #SpringBootApplication does not help and from what I read it should also not be needed.
pom.xml:
<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<groupId>helloWorld.com.example</groupId>
<artifactId>helloWorld</artifactId>
<version>0.0.1-SNAPSHOT</version>
<packaging>war</packaging>
<name>fireCommerce</name>
<description>Demo project for Spring Boot</description>
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>2.0.4.RELEASE</version>
<relativePath/> <!-- lookup parent from repository -->
</parent>
<properties>
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
<project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
<java.version>1.8</java.version>
</properties>
<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-data-jpa</artifactId>
</dependency>
<dependency>
<groupId>com.h2database</groupId>
<artifactId>h2</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-devtools</artifactId>
<scope>runtime</scope>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-tomcat</artifactId>
<scope>provided</scope>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-test</artifactId>
<scope>test</scope>
</dependency>
</dependencies>
<build>
<plugins>
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
</plugin>
<plugin>
<groupId>com.microsoft.azure</groupId>
<artifactId>azure-webapp-maven-plugin</artifactId>
<version>1.1.0</version>
<configuration>
<resourceGroup>maven-projects</resourceGroup>
<appName>${project.artifactId}-${maven.build.timestamp}</appName>
<region>westus</region>
<javaVersion>1.8</javaVersion>
<deploymentType>war</deploymentType>
</configuration>
</plugin>
</plugins>
</build>
</project>
link to the github project
You are excluding the autoconfiguration of JPA repositories. Remove the line from application.properties to let Spring make CustomerRepository a bean and configure it.
spring.autoconfigure.exclude=org.springframework.boot.autoconfigure.jdbc.DataSourceAutoConfiguration
In my case, I just forgot to add #Component to Impl class of interface!
These errors may be due to absence of one or more stereotype annotations.
I changed this Class Level Annotation from my Application Class.
From:
#SpringBootApplication(exclude = {DataSourceAutoConfiguration.class })
To:
#SpringBootApplication
Try Adding the #ComponentScan("package.path.to.your.repository") annotation above Application class.
- Just make sure your repository is in the the same package path that is written in #ComponentScan
#SpringBootApplication
#ComponentScan("helloworld")
public class Application extends SpringBootServletInitializer {
//your stuff
}
I had the same issue and everything was good except adding the below dependecies.
<dependency>
<groupId>org.springframework.data</groupId>
<artifactId>spring-data-jpa</artifactId>
<version>2.4.2</version>
And, It worked for me
you need to add #Repository in repository

Configuring Jersey with Spring boot

I am trying to configure the spring boot with jersey but it seems jersey annotations are not working with spring boot.
can you please help me out.
I have tried #RestController instead of #Component and #RequestMapping instead of #Path in service class.
pom.xml
<project>
<modelVersion>4.0.0</modelVersion>
<groupId>org.hotel</groupId>
<artifactId>reservations</artifactId>
<version>0.0.1-SNAPSHOT</version>
<packaging>jar</packaging>
<name>reservations</name>
<description>Demo project for Spring Boot</description>
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>1.5.8.RELEASE</version>
<relativePath/>
<!-- lookup parent from repository -->
</parent>
<properties>
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
<project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
<java.version>1.8</java.version>
</properties>
<dependencies>
<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-actuator</artifactId>
    <version>1.4.2.RELEASE</version>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-data-jpa</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-thymeleaf</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-jersey</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
<dependency>
<groupId>com.h2database</groupId>
<artifactId>h2</artifactId>
<scope>runtime</scope>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-test</artifactId>
<scope>test</scope>
</dependency>
</dependencies>
<build>
<plugins>
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
</plugin>
</plugins>
</build>
</project>
Spring Boot Application Xml
package org.hotel;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
#SpringBootApplication
public class ReservationApplication {
public static void main(String []args){
SpringApplication.run(ReservationApplication.class, args);
}
}
service class with jersey annotations
package org.hotel.webservices;
import org.springframework.stereotype.Component;
import javax.ws.rs.GET;
import javax.ws.rs.Path;
#Component
#Path("/rooms")
public class AddRoomService {
#GET
public String addRoomService(){
return "success";
}
}
Nice tutorial online about this:
Spring Boot Jersey Example July 14, 2017 by Lokesh Gupta. This seems to be the part you're missing.
Jersey Configuration
1: Now we have a JAX-RS resource and we want to access it from spring boot application which include Jersey dependency. Let’s register this resource as Jersey resource.
package com.howtodoinjava.jerseydemo;
import org.glassfish.jersey.server.ResourceConfig;
import org.springframework.stereotype.Component;
#Component
public class JerseyConfig extends ResourceConfig
{
    public JerseyConfig()
    {
        register(UserResource.class);
    }
}
Look at the #Component annotation. It enables this class to be registered while spring boot auto scans the java classes in source folder.
2: ResourceConfig provides advanced capabilities to simplify registration of JAX-RS components.
3: Extend spring boot application with SpringBootServletInitializer.
package com.howtodoinjava.jerseydemo;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.boot.builder.SpringApplicationBuilder;
import org.springframework.boot.web.support.SpringBootServletInitializer;
#SpringBootApplication
public class JerseydemoApplication extends SpringBootServletInitializer
{
    public static void main(String[] args)
    {
        new JerseydemoApplication().configure(new SpringApplicationBuilder (JerseydemoApplication.class)).run(args);
    }
}
Just to add to the answer from Nicholas agreed its an excellent tutorial but if you wish to restructure the project (for example create multiple packages for your resources, models etc) you must ensure that the JerseyConfig class and JerseydemoApplication class are in the same package, otherwise the registration wont work. This is not explicitly mentioned in the tutorial.
I found this while working in intellij ultimate edition and following same tutorial provided by Nicholas above

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