Spring boot sample: Unable to start embedded container error - spring

Question

I am new to spring, so i downloaded jar from spring intializr for maven-web java 1.8 demo. I extracted and imported it to STS to run the main() file and I get below exception. Can some one tell me what's solution for this?
Solutions I tried from web but didn't work:
- Tried adding Hibernate-validator dependency to pom
- Tried adding spring-boot-starter-tomcat dependency to pom
STACK TRACE:
2017-01-26 12:19:32.587 INFO 3816 --- [ main] ationConfigEmbeddedWebApplicationContext : Refreshing org.springframework.boot.context.embedded.AnnotationConfigEmbeddedWebApplicationContext#2e4b8173: startup date [Thu Jan 26 12:19:32 EST 2017]; root of context hierarchy
2017-01-26 12:19:36.442 WARN 3816 --- [ main] ationConfigEmbeddedWebApplicationContext : Exception encountered during context initialization - cancelling refresh attempt: org.springframework.context.ApplicationContextException: Unable to start embedded container; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'tomcatEmbeddedServletContainerFactory' defined in class path resource [org/springframework/boot/autoconfigure/web/EmbeddedServletContainerAutoConfiguration$EmbeddedTomcat.class]: Initialization of bean failed; nested exception is org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'org.springframework.boot.autoconfigure.web.HttpEncodingAutoConfiguration': Unsatisfied dependency expressed through constructor parameter 0; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'spring.http.encoding-org.springframework.boot.autoconfigure.web.HttpEncodingProperties': Initialization of bean failed; nested exception is javax.validation.ValidationException: Unable to create a Configuration, because no Bean Validation provider could be found. Add a provider like Hibernate Validator (RI) to your classpath.
2017-01-26 12:19:36.454 ERROR 3816 --- [ main] o.s.b.d.LoggingFailureAnalysisReporter :
***************************
APPLICATION FAILED TO START
***************************
Description:
The Bean Validation API is on the classpath but no implementation could be found
Action:
Add an implementation, such as Hibernate Validator, to the classpath
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>com.example</groupId>
<artifactId>demo</artifactId>
<version>0.0.1-SNAPSHOT</version>
<packaging>jar</packaging>
<name>demo</name>
<description>Demo project for Spring Boot</description>
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>1.4.3.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-web</artifactId>
</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>
Application file:
package com.example;
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);
}
}

Answer 1

Had the same problem with release version 1.5.9 of Spring Boot.
To add to the answer by Jim Kiley, you should add the following in Maven pom.xml:
<dependency>
<groupId>org.hibernate</groupId>
<artifactId>hibernate-validator</artifactId>
<version>5.3.6.Final</version>
</dependency>
You can use the dependency version under properties section of Spring Boot pom.xml file (spring-boot-dependencies-1.5.9.RELEASE.pom):
<hibernate-validator.version>5.3.6.Final</hibernate-validator.version>
Located under path:
/.m2/repository/org/springframework/boot/spring-boot-dependencies/1.5.9.RELEASE/spring-boot-dependencies-1.5.9.RELEASE.pom

Answer 2

As the output says, you need to:
Add an implementation, such as Hibernate Validator, to the classpath
Since you're using Maven, that means you need to add the Hibernate Validator to your pom.xml's dependencies.

Answer 3

First of all, your pom.xml settings are correct.
spring-boot-starter-web has the dependency to hibernate-validator.
So in your project, you don't need to specify the dependency to hibernate-validator. Otherwise, what's the purpose to use maven?
So back to the resolution, the steps I did to resolve the problem are:
Goto project folder where the pom.xml is located.
Run mvn verify
The command will download the missing jar again from the repository and also check the correctness(corrupted or not) of jars in maven local repository.
If you see the warning messages similar to following:
[WARNING] error reading /home/vagrant/.m2/repository/org/apache/tomcat/embed/tomcat-embed-core/8.5.6/tomcat-embed-core-8.5.6.jar; invalid LOC header (bad signature)
[WARNING] error reading /home/vagrant/.m2/repository/org/hibernate/hibernate-validator/5.2.4.Final/hibernate-validator-5.2.4.Final.jar; invalid LOC header (bad signature)
[WARNING] error reading /home/vagrant/.m2/repository/com/fasterxml/jackson/core/jackson-core/2.8.4/jackson-core-2.8.4.jar; invalid LOC header (bad signature)
Then this means that the jars downloaded by maven previously has been corrupted.
To correct this, please delete those corrupted jars and run mvn verify again to re-download them and also ensure that there's no warning for jars.
Go back to your IDE(STS or Eclipse), update your project and run the application again.
In above error the hibernate-validator-5.2.4.Final.jar is the hibernate validator that in quesion.

Answer 4

I met same issue and resolved it by delete these two folders under .m2
com\fasterxml --> delete it will resolve TypeResovler issue.
org\springframework --> delete it will resolve lack of validator
issue.
then the program works.

Answer 5

I faced the same issue while runs the application and resolved the issue by deleting the .m2 folder.
.m2/repository