This repository is for an example application built in my Spring Framework 5 - Beginner to Guru online course
The application is a simple Spring Boot 2 / Spring Framework 5 web application.
If you would like learn about what's new in Spring Framework 5, click here
You can learn about my Spring Framework 5 Online course here.
You can learn about my Spring Framework 5 Online course here.
Check out this section for answers to frequently asked questions!
| Recommended | Reference | Notes |
|---|---|---|
| Oracle Java 8 JDK | Download | Java 11 is okay, see notes in FAQ |
| IntelliJ 2018 or Higher | Download | Ultimate Edition recommended |
| Maven 3.6.0 or higher | Download | Installation Instructions |
| Gradle 4.8 or higher | Download | Note: Use Version 5 or higher if using Java 11 |
| Git 2.15 or higher | Download | |
| Git GUI Clients | Downloads | Not required. But can be helpful if new to Git. SourceTree is a good option for Mac and Windows users. |
| Spring Boot 2.1 or higher | What's new |
Each course section has a Q&A Section. This should always be your first stop. Thousands of people have take this course. Check to see if someone else asked a question related to your problem.
If not, share your problem here. The instructor, teacher's assistants, and other students watch and answer questions.
By enrolling in Spring Framework 5: Beginner to Guru you can join a Slack community exclusive to this course.
In Slack you can get help 24 hrs a day, 7 days a week. The instructor, teachers assistants, and other students monitor Slack.
See section 1 of the course for instructions on how to join.
These resources are monitored by the instructor, teachers assistants, and other students.
Asking your question in the public forums actually help others learn too. When you go outside the community, this is lost. Also, the instructor is not always on-line and does take days off. You are likely to get a much faster response using Udemy Q&A or Slack.
This helps others re-create your problem.
Example of error shared:
Failed to execute goal org.apache.maven.plugins:maven-release-plugin:2.5.3:prepare (default-cli) on project pet-clinic: Maven execution failed, exit code: '1' -> [Help 1]In the above example, it is impossible to tell what the root cause is. The person has not shared enough details.
When seeking help, help others help you!
Create a Gist of the error output to share.
Pro-Tip - You can create a gist from the run window of IntelliJ. In the console, right click > select option for create gist.
Using a gist is usually a better option!
Unfortunately, the course has been pirated. Support is for people who are legitimately enrolled in the course. There is no way to verify enrollment from GitHub. Thus, problems raised on GitHub will not be addressed.
Exception: One exception is the Pet Clinic project, which is being treated as a community project.
Majority of the course has been developed on Java 8. The course is being updated to Java 11.
If you wish to use Java 9 or higher, please modify the following:
Note: If you are on Java 9, or Java 10 you should consider updating to Java 11.
Update your Maven POM properties to reflect the Java version.
<properties>
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
<project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
<java.version>11</java.version>
<jaxb.version>2.3.0</jaxb.version>
<maven.compiler.source>${java.version}</maven.compiler.source>
<maven.compiler.target>${java.version}</maven.compiler.target>
</properties>
The JAXB API is no longer included with Java in Java 9 and higher. You will need to add this dependency as follows:
<dependency>
<groupId>javax.xml.bind</groupId>
<artifactId>jaxb-api</artifactId>
<version>${jaxb.version}</version>
</dependency>
<dependency>
<groupId>com.sun.xml.bind</groupId>
<artifactId>jaxb-core</artifactId>
<version>${jaxb.version}</version>
</dependency>
<dependency>
<groupId>com.sun.xml.bind</groupId>
<artifactId>jaxb-impl</artifactId>
<version>${jaxb.version}</version>
</dependency>No. Open JDK should work just as well.
No, the Oracle JDK is free to use for development.
No, all source code examples use Maven or Gradle. Any modern Java IDE supports these build tools.
Yes. However, please understand the instructor has not used Eclipse in over 10 years and will not be able to answer IDE related questions.
Yes. The Community edition of IntelliJ is very good. The Ultimate Edition does have advanced features to support Spring Framework development. These features are used in the course, and will not be available in the Community Edition.
See section 1 of the course. There is a lecture with a sign-up link to register. You can download IntelliJ Ultimate with a free 30 day trial right away. You will be emailed a code with instructions within 3-5 business days. (often faster)
If it has been more than 5 days, check your spam folder. (Almost always there!) If not found, email John Thompson. If messaging on Udemy please include the email you registered with.
This is often one of the following:
- You are entering the code as a license in IntelliJ. It is not a license code. It is a code for JetBrains to issue you a 120 day license. Use this link to register with JetBrains.
- If you get the error
This coupon code is not applicable to the product.often it is because the email you are using has been registered with JetBrains in the past. Try using a different email account.
Yep! The instructor typically runs on the EAP version to get all the latest features. The EAP version is usually very stable. Checkout the latest EAP version here
This is a generic error page generated by Spring Boot. The root cause can be many different things.
If you see this web page, you need to view the Spring Boot console messages to determine the root cause.
May see in console log:
***************************
APPLICATION FAILED TO START
***************************
Description:
The Tomcat connector configured to listen on port 8080 failed to start. The port may already be in use or the connector may be misconfigured.
Action:
Verify the connector's configuration, identify and stop any process that's listening on port 8080, or configure this application to listen on another port.
This means another application is already running on port 8080. You need to find and stop the other application.
By default Spring Boot will configure the datasource as jdbc:h2:mem:testdb
However, if running the H2 database console for the first time, the datasource URL is jdbc:h2:~/test
What happens is the H2 database console is connecting to a different instance of the H2 database console, thus you will not see the database tables.
Solution: When connecting in the H2 Database Console, change the JDBC URL to jdbc:h2:mem:testdb
Spring Boot is trying to build an executable fat JAR with dependencies for a module that should be a normal JAR, thus looking for the main class for the JAR manifest file.
Solution: You need to tell the Spring Boot Maven Plugin to not repackage the jar.
Add the following property to the Maven module you wish packaged as a normal jar.
<properties>
<spring-boot.repackage.skip>true</spring-boot.repackage.skip>
</properties>Note: For Spring Boot 2.1 or Higher! This configuration has changed from earlier versions of Spring Boot.
Sometimes it can be a very small difference. You can use Git to report the differences between your code and the example source code for the lesson.
Note: This will only work if you've forked the original source code example to your GitHub repository.
- Commit all of your changes.
- Add remote for original repo -
git remote add sfgRepo github_url - Fetch remote -
git fetch sfgRepo - Run diff -
git diff HEAD..sfgRepo/master<- update branch name from master to desired branch for lesson
You are running Java 9+ and have not added the JAXB dependencies.
Add the following dependencies to your Maven POM:
<properties>
<jaxb.version>2.3.0</jaxb.version>
</properties>
<dependencies>
<dependency>
<groupId>javax.xml.bind</groupId>
<artifactId>jaxb-api</artifactId>
<version>${jaxb.version}</version>
</dependency>
<dependency>
<groupId>com.sun.xml.bind</groupId>
<artifactId>jaxb-core</artifactId>
<version>${jaxb.version}</version>
</dependency>
<dependency>
<groupId>com.sun.xml.bind</groupId>
<artifactId>jaxb-impl</artifactId>
<version>${jaxb.version}</version>
</dependency>
</dependencies> There are several reasons for this, and a lot of bad advice on the internet.
Please see this blog post!
The CSS resources are generated with Maven. Thus if the project is cleaned, not built, or re-generated with IntelliJ the CSS resources will not exist.
Solution: Just build the project with Maven. mvn clean package
Spring is looking for a bean of a specific type in the context, but is unable to find it. Error is because Spring has not been configured to create a bean for the Java class indicated in the message.
This may be due to several different reasons, but when troubleshooting - keep in mind Spring is telling you that Java class is missing from the context. You need to tell Spring to create a bean of that type.
Try the following:
- Make sure you have a bean of the type configured.
- Is the missing Java class annotated with a Spring stereotype - @Component, @Controller, @RestController, @Service, @Repository?
- Or has the bean been declared in a Java configuration class using the @Bean annotation?
- Is the package of the Java class or configuration class being scanned?
- By default, Spring Boot will do a component scan of the package of the main application class, and all sub-packages. A common mistake is to create a package outside of this package structure. (thus, Spring does not 'see' the configuration)
- If the component is not under the package of the main application class, use the @ComponentScan annotation. See this link for additional information.