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Spring dependency not found

I'm very new to Spring, and also Maven. I'm following along with the book Spring Start Here because it seems friendly. The very first project asks us to add a spring-context dependency to a new project (using maven). I'm using the Intellij Idea community version to follow along, as suggested in the book. But on following the instructions to add the dependency I get an error: Dependency 'org.springframework:spring-context:' not found
Here is my 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>org.myspring</groupId>
<artifactId>start</artifactId>
<version>1.0-SNAPSHOT</version>
<dependencies>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-context</artifactId>
</dependency>
</dependencies>
<properties>
<maven.compiler.source>17</maven.compiler.source>
<maven.compiler.target>17</maven.compiler.target>
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
</properties>
</project>
I think the idea is to add spring dependencies one by one in order to see their purpose. The autocompletion in idea shows an error for the lines
<groupId>org.springframework</groupId>
<artifactId>spring-context</artifactId>
I have already tried updating the maven>repositories in the ide settings but still get the same error.
Also, I found the page https://mvnrepository.com/artifact/org.springframework/spring-context which seems to suggest I have used the correct groupId and artifactId names
Edit: I just removed the empty version tag in the dependency.

maven usually requires the version tag to specify the version
Most cases where no version is specified are when the project inherits pom files
For example
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>3.0.0</version>
<relativePath/> <!-- lookup parent from repository -->
</parent>
Unlike npm and pip, it does not automatically select the latest version

Project build error.Non resolvalbe parent POM in pom.xml in java

I am getting below error in pom.xml in springboot java application. I changed java version ,springboot version but error remains same. what should I do?
below is my 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>2.5.13</version>
<relativePath/> <!-- lookup parent from repository -->
</parent>
<groupId>com.example</groupId>
<artifactId>demo</artifactId>
<version>0.0.1-SNAPSHOT</version>
<name>demo</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>
</dependencies>
<build>
<plugins>
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
</plugin>
</plugins>
</build>
</project>
I saw some of the answers and played with relativePath but did not work what should I do?

This is an common problem facing now a days. This error causes because your editor haven't installed the spring boot properly. This you have to install all the maven files properly. Just follow the below steps to solve the problem.
Right click your spring boot project (demo) and select the option maven.
2. From the maven option you will get list of options. There you select update project or select download source.
Then your editor will install all the maven files for your spring boot project. And your error will be resolved.
Or
If it does not work just uninstall your spring tool suite and reinstall properly.
Any clarification please don't hesitate to comment your issue.. I am waiting for your comment.. Thank you

How to use a Java class from an application in another application?

I have a class in an application (it is a Spring Boot project), for example:
package com.exemple.spring.springboot.model;
public class Employee {
...
}
And in the pom.xml I have this:
<?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>2.1.7.RELEASE</version>
<relativePath/> <!-- lookup parent from repository -->
</parent>
<groupId>com.exemple.spring</groupId>
<artifactId>spring-boot</artifactId>
<version>0.0.1-SNAPSHOT</version>
...
Now I want to use this class Employee in another application like this:
package com.exe.spring.controller;
import org.springframework.stereotype.Controller;
import com.exemple.spring.springboot.model.Employee;
#Controller
public class EmployeeController {
public Employee getAnEmployee() {
...
}
}
I've build the JAR with mvn clean install for the first app and I've added it in the pom.xml of the second app like this:
<?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.exe.spring</groupId>
<artifactId>rest-client</artifactId>
<version>1.0-SNAPSHOT</version>
<name>rest-client</name>
<description>Demo project for Spring Boot</description>
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>2.1.7.RELEASE</version>
<relativePath/> <!-- lookup parent from repository -->
</parent>
<properties>
<java.version>1.8</java.version>
</properties>
<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
<dependency>
<groupId>com.exemple.spring</groupId>
<artifactId>spring-boot</artifactId>
<version>0.0.1-SNAPSHOT</version>
</dependency>
</dependencies>
And the problem is that I cannot import the Employee class in the EmployeeController class. I've imported it manually like this import com.exemple.spring.springboot.model.Employee;, but Intellij show me an error: Cannot resolve symbol 'springboot'. I see that the dependency is presented in the local repository. It is very weird because Eclipse doens't see anything to import for Employee, and Intellij see the class but when I try to click on "Import class" it doesn't import anything. What can I do to import it correctly? Thank you!

You can not directly add it as dependency, it has to be present in one of certral/ local / remote repository.
You need to add the jar to repo, e.g. local repoository,
mvn install:install-file -DlocalRepositoryPath=repo -DcreateChecksum=true -Dpackaging=jar -Dfile=[your-jar] -DgroupId=[...] -DartifactId=[...] -Dversion=[...]
And then add repository as,
<repository>
<id>repo</id>
<url>file://${project.basedir}/repo</url>
</repository>
Check other optios here

Check follow:
You've used mvn clean install to build and install the first JAR.
You have your JAR in the classpath of the second app. You can see all
of them in "External libraries" in idea. If not, reimport maven project or use auto-import option
Also you can use different maven project structure e.g :
Common parent
|
|-------> first jar
|
|-------> second jar (with first one as a dependency)
I think it should work better for you.

Why Maven fails to manage version of war type dependency?

We have a multi module project where we define several dependencies in parent pom under dependencyManagement tag to manage dependencies version.
It works fine for several modules but one.
Parent pom
<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>my.org.product</groupId>
<artifactId>product-parent</artifactId>
<version>1.0.0-SNAPSHOT</version>
<packaging>pom</packaging>
<properties>
<parade-web.version>2.0.0</parade-web.version>
<!-- other properties -->
</properties>
<modules>
<module>../ProductWeb</module>
<!-- other modules -->
</modules>
<dependencyManagement>
<dependencies>
<dependency>
<groupId>my.org.parade</groupId>
<artifactId>ParadeWeb</artifactId>
<version>${parade-web.version}</version>
</dependency>
<!-- other dependencies -->
</dependencies>
</dependencyManagement>
</project>
ProductWeb pom
<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/maven-v4_0_0.xsd">
<modelVersion>4.0.0</modelVersion>
<parent>
<groupId>my.org.product</groupId>
<artifactId>product-parent</artifactId>
<version>1.0.0-SNAPSHOT</version>
<relativePath>../productparent</relativePath>
</parent>
<artifactId>ProductWeb</artifactId>
<packaging>war</packaging>
<version>1.0.0-SNAPSHOT</version>
<dependencies>
<dependency> <!-- 'dependencies.dependency.version' for my.org.parade:ParadeWeb:jar is missing. -->
<groupId>my.org.parade</groupId>
<artifactId>ParadeWeb</artifactId>
<type>war</type>
</dependency>
<!-- other dependencies -->
</dependencies>
</project>
If I add <version>${parade-web.version}</version> in my ProductWeb pom, NetBeans warns me that
Overrides version defined in DependencyManagement. The managed version is 2.12.2-RELEASE.
The only difference between this dependency and the other is the war type, but I don't get why dependency management fails to sets its version.
UPDATE
I managed to omit version tag but I needed to add <type>war</type> on both parent and child.
I don't understand. Does parent try to resolve dependency version looking for a war but then doesn't pass it through its children?

Add <type>war</type> to the dependencyManagement. This should do the trick.

Thymeleaf dependency causes "Error: Could not find or load main class" in Spring tool suite

I've just downloaded STS and started some maven project and it worked properly, but when I start using thymeleaf it doesn't work.
I see an exclamation mark on the project name, and I get this error Error: Could not find or load main class.
I tried adding its dependencies by myself in the POM, I get that error and it goes away once I remove them!
I also tried creating a "Spring Starter Project" and choosing dependencies "Web and Thymeleaf" to be added, right after the project is created I see a syntax error in the POM in the test dependency Failure to transfer org.springframework.boot:spring-boot-starter-test:jar
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-test</artifactId>
<scope>test</scope>
</dependency>
and when I remove it and its class, I get the same error above.
here is my POM now:
<?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-2</artifactId>
<version>0.0.1-SNAPSHOT</version>
<packaging>jar</packaging>
<name>demo-2</name>
<description>Demo project for Spring Boot</description>
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>1.4.2.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-thymeleaf</artifactId>
</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>

Try to update your maven repository, try first:
mvn dependency:purge-local-repository
Description:
When run on a project, remove the project dependencies from the local
repository, and optionally re-resolve them. Outside of a project,
remove the manually given dependencies.
and then try:
mvn dependency:copy-dependencies
Description:
Goal that copies the project dependencies from the repository to a
defined location.
It seems to me that your local Maven repository doesn't include the thymeleaf dependecy.

The problem was solved after removing failed downloads:
from CMD:
cd %userprofile%\.m2\repository
for /r %i in (*.lastUpdated) do del %i
then updating the project.
It re-downloaded the dependencies and it worked just fine.