explicitlambdaargumenttypes.md

Use explicit types on lambda arguments

org.openrewrite.staticanalysis.ExplicitLambdaArgumentTypes

Adds explicit types on lambda arguments, which are otherwise optional. This can make the code clearer and easier to read. This does not add explicit types on arguments when the lambda has one or two parameters and does not have a block body, as things are considered more readable in those cases. For example, stream.map((a, b) -> a.length); will not have explicit types added.

Tags

• RSPEC-2211

Source

GitHub, Issue Tracker, Maven Central

• groupId: org.openrewrite.recipe
• artifactId: rewrite-static-analysis
• version: 1.0.1

Example

{% tabs %} {% tab title="Test.java" %}

Before

{% code title="Test.java" %}

import java.util.function.BiPredicate;

class Test {
    static void run(BiPredicate<String, Object> bc) {
    }

    static void method() {
        run((a, b) -> {
            return a.isEmpty();
        });
    }
}

{% endcode %}

After

{% code title="Test.java" %}

import java.util.function.BiPredicate;

class Test {
    static void run(BiPredicate<String, Object> bc) {
    }

    static void method() {
        run((String a, Object b) -> {
            return a.isEmpty();
        });
    }
}

{% endcode %}

{% endtab %} {% tab title="Diff" %} {% code %}

--- Test.java
+++ Test.java
@@ -8,1 +8,1 @@

    static void method() {
-       run((a, b) -> {
+       run((String a, Object b) -> {
            return a.isEmpty();

{% endcode %} {% endtab %} {% endtabs %}

Usage

This recipe has no required configuration options. It can be activated by adding a dependency on org.openrewrite.recipe:rewrite-static-analysis:1.0.1 in your build file or by running a shell command (in which case no build changes are needed): {% tabs %} {% tab title="Gradle" %} {% code title="build.gradle" %}

plugins {
    id("org.openrewrite.rewrite") version("6.1.4")
}

rewrite {
    activeRecipe("org.openrewrite.staticanalysis.ExplicitLambdaArgumentTypes")
}

repositories {
    mavenCentral()
}

dependencies {
    rewrite("org.openrewrite.recipe:rewrite-static-analysis:1.0.1")
}

{% endcode %} {% endtab %} {% tab title="Maven POM" %} {% code title="pom.xml" %}

<project>
  <build>
    <plugins>
      <plugin>
        <groupId>org.openrewrite.maven</groupId>
        <artifactId>rewrite-maven-plugin</artifactId>
        <version>5.2.4</version>
        <configuration>
          <activeRecipes>
            <recipe>org.openrewrite.staticanalysis.ExplicitLambdaArgumentTypes</recipe>
          </activeRecipes>
        </configuration>
        <dependencies>
          <dependency>
            <groupId>org.openrewrite.recipe</groupId>
            <artifactId>rewrite-static-analysis</artifactId>
            <version>1.0.1</version>
          </dependency>
        </dependencies>
      </plugin>
    </plugins>
  </build>
</project>

{% endcode %} {% endtab %}

{% tab title="Maven Command Line" %} {% code title="shell" %} You will need to have Maven installed on your machine before you can run the following command.

mvn -U org.openrewrite.maven:rewrite-maven-plugin:run \
  -Drewrite.recipeArtifactCoordinates=org.openrewrite.recipe:rewrite-static-analysis:RELEASE \
  -Drewrite.activeRecipes=org.openrewrite.staticanalysis.ExplicitLambdaArgumentTypes

{% endcode %} {% endtab %} {% endtabs %}

Contributors

• Tyler Van Gorder
• Jonathan Leitschuh
• Sam Snyder
• Knut Wannheden

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