Spring Boot is released under the Apache 2.0 license. If you would like to contribute something, or simply want to hack on the code this document should help you get started.
This project adheres to the Contributor Covenant code of conduct. By participating, you are expected to uphold this code. Please report unacceptable behavior to [email protected].
We use GitHub issues to track bugs and enhancements. If you have a general usage question
please ask on Stack Overflow. The Spring Boot team and the
broader community monitor the spring-boot
tag.
If you are reporting a bug, please help to speed up problem diagnosis by providing as much information as possible. Ideally, that would include a small sample project that reproduces the problem.
If you think you have found a security vulnerability in Spring Boot please DO NOT disclose it publicly until we’ve had a chance to fix it. Please don’t report security vulnerabilities using GitHub issues, instead head over to https://pivotal.io/security and learn how to disclose them responsibly.
Before we accept a non-trivial patch or pull request we will need you to sign the Contributor License Agreement. Signing the contributor’s agreement does not grant anyone commit rights to the main repository, but it does mean that we can accept your contributions, and you will get an author credit if we do. Active contributors might be asked to join the core team, and given the ability to merge pull requests.
None of these is essential for a pull request, but they will all help. They can also be added after the original pull request but before a merge.
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We use the Spring JavaFormat project to apply code formatting conventions. If you use Eclipse and you follow the ‘Importing into eclipse’ instructions below you should get project specific formatting automatically. You can also install the Spring JavaFormat IntelliJ Plugin or format the code from the Maven build by running
./mvnw io.spring.javaformat:spring-javaformat-maven-plugin:apply. -
The build includes checkstyle rules for many of our code conventions. Run
./mvnw validateif you want to check you changes are compliant. -
Make sure all new
.javafiles to have a simple Javadoc class comment with at least an@authortag identifying you, and preferably at least a paragraph on what the class is for. -
Add the ASF license header comment to all new
.javafiles (copy from existing files in the project) -
Add yourself as an
@authorto the.javafiles that you modify substantially (more than cosmetic changes). -
Add some Javadocs.
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A few unit tests would help a lot as well — someone has to do it.
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If no-one else is using your branch, please rebase it against the current master (or other target branch in the main project).
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When writing a commit message please follow these conventions, if you are fixing an existing issue please add
Fixes gh-XXXXat the end of the commit message (whereXXXXis the issue number).
If you don’t have an IDE preference we would recommend that you use Spring Tools Suite or Eclipse when working with the code. We use the M2Eclipse eclipse plugin for maven support. Other IDEs and tools should also work without issue.
Spring Boot source can be build from the command line using
Apache Maven on JDK 1.8 or above.
We include ‘Maven Wrapper’ scripts (./mvnw or mvnw.bat) that you can run rather
than needing to install Maven locally.
The project can be built from the root directory using the standard Maven command:
$ ./mvnw clean install
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Note
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You may need to increase the amount of memory available to Maven by setting
a MAVEN_OPTS environment variable with the value -Xmx512m
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If you are rebuilding often, you might also want to skip the tests and the execution of checkstyle until you are ready to submit a pull request:
$ ./mvnw clean install -DskipTests -Pfast
You can run a full build using the following command:
$ ./mvnw -Pfull clean install
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Note
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As for the standard build, you may need to increase the amount of memory available
to Maven by setting a MAVEN_OPTS environment variable with the value -Xmx512m. We
generate more artifacts when running the full build (such as Javadoc jars), so you may
find the process a little slower than the standard build.
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Tip
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If you want to run a build without the samples and integration tests, building the
$ ./mvnw -f spring-boot-project -Pfull clean install |
You can import the Spring Boot code into any Eclipse Oxygen based distribution. The easiest
way to setup a new environment is to use the Eclipse Installer with the provided
.setup file (in the /eclipse folder).
Spring Boot includes a .setup files which can be used with the Eclipse Installer to
provision a new environment. To use the installer:
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Download and run the latest Eclipse Installer from eclipse.org/downloads/ (under "Get Eclipse").
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Switch to "Advanced Mode" using the drop down menu on the right.
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Select “Eclipse IDE for Java Developers” under “Eclipse.org” as the product to install and click “next”.
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For the “Project” click on “+” to add a new setup file. Select “Github Projects” and browser for
<checkout>/eclipse/spring-boot-project.setupfrom your locally cloned copy of the source code. Click “OK” to add the setup file to the list. -
Double-click on “Spring Boot” from the project list to add it to the list that will be provisioned then click “Next”.
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Click show all variables and make sure that “Checkout Location” points to the locally cloned source code that you selected earlier. You might also want to pick a different install location here.
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Click “Finish” to install the software.
Once complete you should find that a local workspace has been provisioned complete with all required Eclipse plugins. Projects will be grouped into working-sets to make the code easier to navigate.
If you prefer to install Eclipse yourself you should use the M2Eclipse eclipse plugin. If you don’t already have m2eclipse installed it is available from the "Eclipse marketplace".
Spring Boot includes project specific source formatting settings, in order to have these work with m2eclipse, we provide an additional Eclipse plugin that you can install:
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Select “Help” → “Install New Software”.
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Add
https://dl.bintray.com/spring/javaformat-eclipse/as a site. -
Install "Spring Java Format".
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Note
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The plugin is optional. Projects can be imported without the plugins, your code changes just won’t be automatically formatted. |
With the requisite eclipse plugins installed you can select
import existing maven projects from the file menu to import the code. You will
need to import the root spring-boot pom and the spring-boot-samples pom separately.
To open the project in IntelliJ IDEA, select “File” → “Open” and then click on the
root pom.xml.
If you haven’t done so, install the formatter plugin so that proper formatting rules are applied automatically when you reformat code in the IDE.
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Download the latest IntelliJ IDEA plugin.
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Select “IntelliJ IDEA” → “Preferences”.
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Select “Plugins”.
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Select the wheel and “Install Plugin from Disk…”.
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Select the jar file you’ve downloaded.
The formatter does not cover all rules (such as order of imports) and an additional file needs to be added.
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Select “IntelliJ IDEA” → “Preferences”.
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Select “Editor” → “Code Style”.
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Select the wheel and “Import Scheme” → “IntelliJ IDEA code style XML”.
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Select
idea/codeStyleConfig.xmlfrom this repository.
The sample applications are used as integration tests during the build (when you
./mvnw install). Due to the fact that they make use of the spring-boot-maven-plugin
they cannot be called directly, and so instead are launched via the
maven-invoker-plugin. If you encounter build failures running the integration tests,
check the build.log file in the appropriate sample directory.
Some files in the git repository may exceed the Windows maximum file path (260
characters), depending on where you clone the repository. If you get Filename too long
errors, set the core.longPaths=true git option:
git clone -c core.longPaths=true https://github.com/spring-projects/spring-boot