Formatting

Elide bundles google-java-format 1.37.0, Netflix jfmt 0.9.0 and ktfmt 0.65. elide format runs the Java and Kotlin formatters; elide javaformat and elide ktfmt run one.

Terminal

bash

elide format -- src
elide javaformat -- Hello.java src/main/java
elide ktfmt -- Hello.kt src/main/kotlin

Formatting Java and Kotlin source files with Elide

 ~/demo  bat src/Greeter.kt
───────┬────────────────────────────────────────────────────────────────────────────────────────────
       │ File: src/Greeter.kt
       │ Size: 161 B
───────┼────────────────────────────────────────────────────────────────────────────────────────────
   1   │ package demo
   2   │ data class User( val id:Int,val name:String )
   3   │ 
   4   │ class Greeter(val users:List<User>){
   5   │ fun greet(id:Int)=users.firstOrNull{it.id==id}?.name?:"world"
   6   │ }
───────┴────────────────────────────────────────────────────────────────────────────────────────────
 ~/demo  elide format -- src
✅  Formatted 1 Java sources
✅  Formatted 1 Kotlin sources
 ~/demo  bat src/Greeter.kt
───────┬────────────────────────────────────────────────────────────────────────────────────────────
       │ File: src/Greeter.kt
       │ Size: 177 B
───────┼────────────────────────────────────────────────────────────────────────────────────────────
   1   │ package demo
   2   │ 
   3   │ data class User(val id: Int, val name: String)
   4   │ 
   5   │ class Greeter(val users: List<User>) {
   6   │   fun greet(id: Int) = users.firstOrNull { it.id == id }?.name ?: "world"
   7   │ }
───────┴────────────────────────────────────────────────────────────────────────────────────────────

Files and directories go after -- and are rewritten in place. Each file is reported as unchanged, rewritten, would be rewritten, or failed to parse. javaformat also accepts -i:

Terminal

bash

elide javaformat -- -i Hello.java

Check formatting

-n or --dry-run after -- writes nothing and exits 1 if a file would change. --set-exit-if-changed is accepted; there is no --check.

Terminal

bash

elide format -- -n src
elide javaformat -- -n src/main/java
elide ktfmt -- -n src/main/kotlin

In check mode, two Elide options (before --) report what would change:

Terminal

bash

elide format --list-files -- -n src
elide format --list-diffs -- -n src
elide format --list-diffs=5 -- -n src

Option	Output
`--list-files`	Paths that would change, one per line on stdout.
`--list-diffs=N`	Unified diffs when at most `N` files fail, otherwise paths. Use `=N`, not a separate value.

Both work on javaformat and ktfmt too.

Formatter flags

Everything after -- is passed to the formatter, including argument files and style switches (--google-style, --kotlinlang-style, --aosp):

Terminal

bash

elide ktfmt -- --google-style @kotlin-sources.txt

elide javaformat --help and elide ktfmt --help show Elide’s options and how to show the formatter’s help.

Select project sources

With no paths after --, elide format formats the Java and Kotlin sources of the current project:

Terminal

bash

elide format
elide format --install -- --jfmt
elide format --install -- --jfmt -n

--install is an Elide option on elide format, before --. It runs the dependency installation step first and stops if installation fails. Use it when jfmt needs project dependency types to resolve imports. To run only the Java formatter with those dependencies, install first and name the Java sources:

Terminal

bash

elide install
elide javaformat -- --jfmt src/main/java

jfmt dialect

--jfmt formats Java with jfmt instead of google-java-format: 4-space blocks, 8-space continuations, no column limit, braces around every statement body, and static imports after ordinary ones.

Terminal

bash

elide javaformat -- --jfmt src/main/java
elide format -- --jfmt -n src

Selecting jfmt changes Java formatting only; elide format still uses ktfmt for Kotlin files.

jfmt is a fixed style, so --jfmt cannot be combined with --aosp, --fix-imports-only or the --skip-* flags.

Resolve and rewrite imports

Like upstream jfmt, Elide first runs jfmt’s import pass over the files of a run: wildcard imports are expanded to the types used and qualified type names are shortened. The pass attributes the files together with javac, so their dependencies must be resolvable. Where upstream then fails the run, Elide warns, shows javac’s errors and formats the files without the pass. Name the dependencies with javac’s options (--class-path, --module-path, --release and the rest jfmt accepts). Without --class-path, each file is attributed against the class path elide install exported for the project it belongs to; elide format --install runs elide install first, which returns quickly when nothing needs installing. Classes from files outside the run resolve through the source roots the files’ package declarations imply, unless --source-path names others. Standard input is formatted without the pass, as upstream does.

For example, a file using List from import java.util.*; and declaring a field as java.time.Instant created = java.time.Instant.now(); receives explicit imports for List and Instant, and uses Instant in the field declaration and initializer. This needs type resolution; ordinary whitespace formatting does not. When the pass reports missing types, install the owning project’s dependencies or pass an explicit classpath and rerun to obtain the import rewrites. Formatting can otherwise succeed with the warning and leave those imports unresolved.

With no files named, --source-path selects every Java source under it, as jfmt --source-path does, in place of the project’s sources; --module-source-path only sets where the pass looks for sources.

Terminal

bash

elide javaformat -- --jfmt --class-path libs/widgets.jar src/main/java
elide format --install -- --jfmt

Format a selection

--lines, --offset and --length select part of one file, as they do for google-java-format. jfmt formats only the selected code, then sorts imports and removes unused ones over the whole file. Passes that rewrite the whole file are skipped for a selection: the import pass above, adding braces around statement bodies, and repeating until the output is stable.

Terminal

bash

elide javaformat -- --jfmt --lines 10:24 src/main/java/demo/Wild.java
elide javaformat -- --jfmt --offset 120 --length 80 src/main/java/demo/Wild.java

Line ranges are one-based and inclusive; offsets and lengths count characters. A selection is not a guarantee that imports stay untouched: unused-import removal and import ordering still apply to the entire file. Run without selection flags when you want the type-based import pass and brace insertion as well.