Could not find method bootJar() for arguments - spring-boot

Question

While building the gradle project I am getting below error-
FAILURE: Build failed with an exception.
Where:
Build file '/Users/vdubey/Documents/microservices/workspace/Promo-Service/build.gradle' line: 30
What went wrong:
A problem occurred evaluating root project 'Promo-Service'.
Could not find method bootJar() for arguments [build_3jq74tz48uic808y18txabjvx$_run_closure1#5c4aa147] on root project 'Promo-Service' of type org.gradle.api.Project.
Try:
Run with --stacktrace option to get the stack trace. Run with --info or --debug option to get more log output.
Get more help at https://help.gradle.org
Any clue why it is failing?

Answer 1

I had this error while following the Spring Boot with Docker guide because my application is using Spring Boot 1.5.10.RELEASE and bootRun was only introduced in 2.0.0.
Luckily, the Spring Boot Docker guide code is in a Github repository, so I was able to navigate back to a pre 2.0.0 version: https://github.com/spring-guides/gs-spring-boot-docker/tree/8933f6efa9a94cf596095658dc0b81986d11a3ec
See the completed build.gradle file for 1.5.10-RELEASE:
// This is used as the docker image prefix (org)
group = 'springio'
jar {
baseName = 'gs-spring-boot-docker'
version = '0.1.0'
}
// tag::task[]
docker {
name "${project.group}/${jar.baseName}"
files jar.archivePath
buildArgs(['JAR_FILE': "${jar.archiveName}"])
}
// end::task[]

Answer 2

Consider checking the presence of gradle plugin for Spring Boot:
https://plugins.gradle.org/plugin/org.springframework.boot
For Gradle 2.1 and later:
plugins {
id "org.springframework.boot" version "2.1.0.RELEASE"
}
For older Gradle versions:
buildscript {
repositories {
maven {
url "https://plugins.gradle.org/m2/"
}
}
dependencies {
classpath "org.springframework.boot:spring-boot-gradle-plugin:2.1.0.RELEASE"
}
}
apply plugin: "org.springframework.boot"

Answer 3

I had this problem when I am following official Spring testing-web guide. They offer initial gradle file as below.
buildscript {
repositories { mavenCentral() }
}
plugins { id "io.spring.dependency-management" version "1.0.4.RELEASE" }
ext { springBootVersion = '2.0.5.RELEASE' }
apply plugin: 'java'
apply plugin: 'eclipse'
apply plugin: 'idea'
bootJar {
baseName = 'gs-testing-web'
version = '0.1.0'
}
repositories {
mavenCentral()
}
sourceCompatibility = 1.8
targetCompatibility = 1.8
dependencies {
compile("org.springframework.boot:spring-boot-starter-web")
testCompile("org.springframework.boot:spring-boot-starter-test")
}
task wrapper(type: Wrapper) {
gradleVersion = '4.6'
}
But when I run the ./gradlew clean command I get the below exception
Could not find method bootJar() for arguments [] on root project '' of type org.gradle.api.Project.
The problem is instead of using plugins { id "io.spring.dependency-management" version "1.0.4.RELEASE" } use id "org.springframework.boot" version "2.1.3.RELEASE". Also don't forget the java and io.spring.dependency-management plugins.
apply plugin: 'java'
apply plugin: 'io.spring.dependency-management'
8.1. Reacting to the Java plugin
When Gradle’s java plugin is applied to a project, the Spring Boot plugin:
Creates a BootJar task named bootJar that will create an executable,
fat jar for the project. The jar will contain everything on the
runtime classpath of the main source set; classes are packaged in
BOOT-INF/classes and jars are packaged in BOOT-INF/lib
8.4. Reacting to the dependency management plugin
When the io.spring.dependency-management plugin is applied to a
project, the Spring Boot plugin will automatically import the
spring-boot-dependencies bom.
I shared valid build.gradle file below which can be a starting point for anyone who have this problem.
/*
* This file was generated by the Gradle 'init' task.
*
* This generated file contains a sample Java project to get you started.
* For more details take a look at the Java Quickstart chapter in the Gradle
* user guide available at https://docs.gradle.org/4.6/userguide/tutorial_java_projects.html
*/
plugins {
id "org.springframework.boot" version "2.1.3.RELEASE"
}
apply plugin: 'idea'
apply plugin: 'java'
apply plugin: 'io.spring.dependency-management'
ext {
springBootVersion = '2.1.3.RELEASE'
}
// In this section you declare where to find the dependencies of your project
repositories {
// You can declare any Maven/Ivy/file repository here.
mavenCentral()
}
bootJar {
mainClassName = 'com.softwarelabs.App'
baseName = 'spring-boot-integration-test'
version = '0.1.0'
}
sourceCompatibility = 1.8
targetCompatibility = 1.8
dependencies {
compile("org.springframework.boot:spring-boot-starter-web")
// This dependency is found on compile classpath of this component and consumers.
compile 'com.google.guava:guava:23.0'
testCompile("org.springframework.boot:spring-boot-starter-test")
// Use JUnit test framework
testCompile 'junit:junit:4.12'
}
task wrapper(type: Wrapper) {
gradleVersion = '4.6'
}
For more details please check the spring boot gradle plugin documentation getting started part.
Check how the Spring Boot plugin reacts by other plugins.

Answer 4

I had this error while building a repository I had downloaded.
I was able to resolve the same by modifying my build.gradle to include a buildscript dependency for spring-boot-gradle-plugin and apply org.springframework.boot as a plugin
buildscript {
ext {
springBootVersion = '<Spring boot version>'
}
repositories {
...<my repository config>...
}
// These are gradle build dependencies and not application requirements
dependencies {
...<other dependencies>...
classpath "org.springframework.boot:spring-boot-gradle-plugin:${springBootVersion}"
}
}
apply plugin: 'org.springframework.boot'