Code Formatting with Spotless

Not everyone follows or likes the same code formatting style. It changes from person to person.

Even the tiny formatting changes make a big readability difference

Scenario 1: Eclipse Java Format

@Getter
private final String value;
@Autowired
private Testclass testObj;
List<String> names = asList("John", "Jack", "Jacob");

List<String> captains = names.stream().map(name -> "Captain " + name).collect(toList());

Scenario 2: Google Java Format

@Getter private final String value;       
@Autowired private Testclass testObj;
List<String> names = asList("John", "Jack", "Jacob");

List<String> captains = names.stream()
      .map(name -> "Captain " + name)
      .collect(toList());

Do you find considerable differences between the above scenarios? This is just a sample, the formatting can impact the readability of the code to a greater extent.

Source: Google

Now, let's see a flexible way for setting it up in Gradle.

Step 1:

Add the spotless plugin to the Gradle file

plugins {
id ‘com.diffplug.spotless’ version ‘5.14.3’
}
apply plugin: ‘com.diffplug.spotless’

Step 2:

Add the dependency library

implementation ‘com.diffplug.spotless:spotless-plugin-gradle:6.11.0’

Step 3:

Add the version of spotless

ext {
spotlessVersion = “3.13.0”
}

Step 4:

Add the following script to the Gradle file,

spotless {
java {
// This path needs to be relative to each project
target fileTree(‘.’) {
include ‘**/src/*/java/**/*.java’
}
removeUnusedImports()
googleJavaFormat(“1.15.0”).aosp()
// eclipse()
importOrder ‘java’, ‘’, ‘org.web3j’, ‘\\#’
trimTrailingWhitespace()
endWithNewline()
}
}

Step 5:

Run

./gradlew build
./gradlew :spotlessApply

We are done !!