coc-java

Fork of vscode-java to works with coc.nvim.

Quick Start

1. Install this extension by run command:

:CocInstall coc-java

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.

Note: this extension would download latest jdt.ls for you when not found.

Setting the JDK

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

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

This JDK will be used to launch the Java Language Server. And by default, will be used to compile your projects.

If you need to compile your projects against a different JDK version, it's recommended you configure the java.configuration.runtimes property in your user settings, eg:

"java.configuration.runtimes": [
  {
    "name": "JavaSE-1.8",
    "path": "/path/to/jdk-8",
  },
  {
    "name": "JavaSE-11",
    "path": "/path/to/jdk-11",
  },
  {
    "name": "JavaSE-14",
    "path": "/path/to/jdk-14",
    "default": true
  },
]

The default runtime will be used when you open standalone Java files.

Features

• Maven pom.xml project support
• Basic Gradle Java project support
• As you type reporting of parsing and compilation errors
• Code completion
• Code actions / Refactoring
• Javadoc hovers
• Organize imports
• Type search
• Code outline
• 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.

Available commands

The following commands are available:

• java.updateLanguageServer: download latest jdt.ls from eclipse.org.
• java.projectConfiguration.update: 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.serverLog: opens the Java Language Server log file, useful for troubleshooting problems.
• java.workspace.compile: manually triggers compilation of the workspace.
• java.action.organizeImports: Organize imports in the currently opened Java file.
• java.open.formatter.settings: Open the Eclipse formatter settings. Creates a new settings file if none exists.
• java.clean.workspace: Clean the Java language server workspace.

Supported settings

The following settings are supported:

• java.enabled: When false, coc-java is disabled, default true.
• java.home : Absolute path to JDK 8 home folder used to launch the Java Language Server. Requires coc server restart.
• java.jdt.ls.vmargs : Extra VM arguments used to launch the Java Language Server. Requires coc server restart.
• java.jdt.ls.home : Directory contains jdt.ls server, would be used instead of bundled server when specified.
• 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 : Absolute 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.maven.enabled : Enable/disable the Maven importer.
• java.autobuild.enabled : Enable/disable the 'auto build'.
• 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.clean.workspace : Clean the Java language server workspace.
• 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.configuration.runtimes: Map Java Execution Environments to local JDKs.

New in 1.3.0:

• java.maven.downloadSources: Enable/disable eager download of Maven source artifacts.
• 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.

New in 1.3.1:

• 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.
• CodeAction: generate constructors and generate delegateMethods

Troubleshooting

• Run :messages to get echoed messages in vim.
• Text JDT.LS would be in your statusline when you have statusline integration with coc.nvim.
• Enable verbose trace for jdt.ls by add "java.trace.server": "verbose" in your settings file, then check output by :CocCommand workspace.showOutput java
• Run :CocCommand java.open.serverLog to open log of jdt.ls.
• Try :CocCommand java.clean.workspace to clean workspace cache.

License

EPL 1.0, See LICENSE for more information.