Language support for Java ™ for Visual Studio Code

Provides Java ™ language support via Eclipse ™ JDT Language Server, which utilizes Eclipse ™ JDT, M2Eclipse and Buildship.

Quick Start

1. Install the Extension
2. If you do not have a Java Development Kit correctly set
   • Download and install a recent Java Development Kit (latest Java 8 is the minimum requirement).
3. Extension is activated when you first access a Java file
   • Recognizes projects with Maven or Gradle build files in the directory hierarchy.

Features

• Supports code from Java 1.5 to Java 12
• Maven pom.xml project support
• Basic Gradle Java project support
• Standalone Java files support
• As-you-type reporting of parsing and compilation errors
• Code completion
• Code/Source actions / Refactoring
• Javadoc hovers
• Organize imports
• Type search
• Code outline
• Code folding
• Code navigation
• Code lens (references/implementations)
• Highlights
• Code formatting (on-type/selection/file)
• Code snippets
• Annotation processing support (automatic for Maven projects)

Please note that Gradle-based Android projects are not supported.

To launch and debug your Java programs, it's recommended you install Java Debug Extension for Visual Studio Code.

See the changelog for the latest release. You might also find useful information in the project Wiki.

Setting the JDK

The path to the Java Development Kit is searched in the following order:

• the java.home setting in VS Code settings (workspace then user settings)
• the JDK_HOME environment variable
• the JAVA_HOME environment variable
• on the current system path

Available commands

The following commands are available:

• Java:Update Project configuration (Shift+Alt+U): is available when the editor is focused on a Maven pom.xml or a Gradle file. It forces project configuration / classpath updates (eg. dependency changes or Java compilation level), according to the project build descriptor.
• Java:Open Java Language Server log file: opens the Java Language Server log file, useful for troubleshooting problems.
• Java:Force Java compilation (Shift+Alt+B): manually triggers compilation of the workspace.
• Java:Open Java formatter settings: Open the Eclipse formatter settings. Creates a new settings file if none exists.
• Java:Clean the Java language server workspace: Clean the Java language server workspace.
• Java:Attach Source: Attach a jar/zip source to the currently opened binary class file. This command is only available in the editor context menu.

Supported VS Code settings

The following settings are supported:

• java.home : Absolute path to JDK home folder used to launch the Java Language Server. Requires VS Code restart.
• java.jdt.ls.vmargs : Extra VM arguments used to launch the Java Language Server. Requires VS Code restart.
• java.configuration.updateBuildConfiguration : Specifies how modifications on build files update the Java classpath/configuration. Supported values are disabled (nothing happens), interactive (asks about updating on every modification), automatic (updating is automatically triggered).
• java.errors.incompleteClasspath.severity : Specifies the severity of the message when the classpath is incomplete for a Java file. Supported values are ignore, info, warning, error.
• java.trace.server : Traces the communication between VS Code and the Java language server.
• java.configuration.maven.userSettings : Path to Maven's settings.xml.
• java.import.exclusions : Exclude folders from import via glob patterns.
• java.referencesCodeLens.enabled : Enable/disable the references code lenses.
• java.implementationsCodeLens.enabled : Enable/disable the implementations code lenses.
• java.signatureHelp.enabled : Enable/disable signature help support (triggered on ().
• java.format.enabled : Enable/disable the default Java formatter.
• java.contentProvider.preferred : Preferred content provider (see 3rd party decompilers available in vscode-java-decompiler).
• java.import.gradle.enabled : Enable/disable the Gradle importer.
• java.import.gradle.wrapper.enabled: Enable/disable the Gradle wrapper.
• java.import.gradle.version: Gradle version, used if the gradle wrapper is missing or disabled.
• java.import.maven.enabled : Enable/disable the Maven importer.
• java.autobuild.enabled : Enable/disable the 'auto build'.
• java.maxConcurrentBuilds: Set max simultaneous project builds.
• java.completion.favoriteStaticMembers : Defines a list of static members or types with static members.
• java.completion.importOrder : Defines the sorting order of import statements.
• java.progressReports.enabled : [Experimental] Enable/disable progress reports from background processes on the server.
• java.completion.overwrite : When set to true, code completion overwrites the current text. When set to false, code is simply added instead.
• java.format.settings.url : Specifies the url or file path to the Eclipse formatter xml settings.
• java.format.settings.profile : Optional formatter profile name from the Eclipse formatter settings.
• java.format.comments.enabled : Includes the comments during code formatting.
• java.format.onType.enabled : Enable/disable on-type formatting (triggered on ;, } or <return>).
• java.completion.guessMethodArguments : When set to true, method arguments are guessed when a method is selected from as list of code assist proposals.
• java.completion.enabled : Enable/disable code completion support.
• java.configuration.checkProjectSettingsExclusions: Checks if the extension-generated project settings files (.project, .classpath, .factorypath, .settings/) should be excluded from the file explorer. Defaults to true.
• java.foldingRange.enabled: Enable/disable smart folding range support. If disabled, it will use the default indentation-based folding range provided by VS Code.
• java.maven.downloadSources: Enable/disable eager download of Maven source artifacts.
• java.codeGeneration.hashCodeEquals.useInstanceof: Use 'instanceof' to compare types when generating the hashCode and equals methods. Defaults to false.
• java.codeGeneration.hashCodeEquals.useJava7Objects: Use Objects.hash and Objects.equals when generating the hashCode and equals methods. This setting only applies to Java 7 and higher. Defaults to false.
• java.codeGeneration.useBlocks: Use blocks in 'if' statements when generating the methods. Defaults to false.
• java.codeGeneration.generateComments: Generate method comments when generating the methods. Defaults to false.
• java.codeGeneration.toString.template: The template for generating the toString method. Defaults to ${object.className} [${member.name()}=${member.value}, ${otherMembers}].
• java.codeGeneration.toString.codeStyle: The code style for generating the toString method. Defaults to STRING_CONCATENATION.
• java.codeGeneration.toString.skipNullValues: Skip null values when generating the toString method. Defaults to false.
• java.codeGeneration.toString.listArrayContents: List contents of arrays instead of using native toString(). Defaults to true.
• java.codeGeneration.toString.limitElements: Limit number of items in arrays/collections/maps to list, if 0 then list all. Defaults to 0.

Troubleshooting

1. Check the status of the language tools on the lower right corner (marked with A on image below). It should show ready (thumbs up) as on the image below. You can click on the status and open the language tool logs for further information in case of a failure.

2. Read the troubleshooting guide for collecting informations about issues you might encounter.

3. Report any problems you face to the project.

Contributing

This is an open source project open to anyone. Contributions are extremely welcome!

For information on getting started, refer to the CONTRIBUTING instructions.

Continuous Integration builds can be installed from http://download.jboss.org/jbosstools/jdt.ls/staging/. Download the most recent java-<version>.vsix file and install it by following the instructions here. Stable releases are archived under http://download.jboss.org/jbosstools/static/jdt.ls/stable/.

Also, you can contribute your own VSCode extension to enhance the existing features by following the instructions here.

Feedback

• File a bug in GitHub Issues,
• Chat with us on Gitter,
• Tweet us with other feedback.

License

EPL 1.0, See LICENSE for more information.