Annotation Processors can't find classes

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1

I’m converting a project from maven to gradle, and we currently have a custom annotation processor that was written in java and maven. It seems that neither the gradle-apt-plugin nor palantir’s processor plugin can seem to find certain classes. i’m receiving this error when gradle tries to compile the project that depends on the annotation processor.

* What went wrong:
Execution failed for task ':lp-server-common:compileJava'.
> java.lang.NoClassDefFoundError: org/apache/velocity/context/Context

This is due to my annotation processor depending on Velocity, but it already has it in it’s pom.xml, so I’m not sure why it’s failing in my gradle build.

2

Here is my top level pom:

I think this has something to do with how I’m configuring the plugins, I’ve got a multimodule project with the top pom.

plugins {
    id "net.ltgt.apt" version "0.13"
    id "org.jetbrains.kotlin.jvm" version "1.1.51"
}

allprojects {
    apply plugin: 'maven'
    apply plugin: 'java'
    apply plugin: 'kotlin'
    apply plugin: 'net.ltgt.apt'

    group = 'com.company.server'
    version = '0.4.0-SNAPSHOT'

    repositories {
        mavenLocal()
        maven {
            credentials {
                username 'name'
                password 'password'
            }
            url "http://blah/repository-maven-snapshots-group"
        }
    }

    dependencies {
        apt 'com.company.annotations:annotation-processors:1.1.0'
        compile group: 'com.company.loanplatform', name: 'lp-common', version: '0.4.0-SNAPSHOT'
        compile group: 'com.company.thirdparty.generated.stuff', name: 'stuff-mismo231', version: '2.3.1'
        compile group: 'org.jetbrains.kotlin', name: 'kotlin-stdlib', version: '1.1.51'
        compile group: 'org.testng', name: 'testng', version: '6.11'
        compile group: 'ch.qos.logback', name: 'logback-classic', version: '1.1.11'
        testCompile group: 'com.nhaarman', name: 'mockito-kotlin', version: '1.5.0'
        testCompile group: 'org.mockito', name: 'mockito-core', version: '2.10.0'
        testCompile group: 'org.codehaus.groovy', name: 'groovy-all', version: '2.4.7'
        testCompile group: 'org.jetbrains.kotlin', name: 'kotlin-test-junit', version: '1.1.51'
        testCompile group: 'org.jetbrains.spek', name: 'spek-api', version: '1.1.5'
        testCompile group: 'org.jetbrains.spek', name: 'spek-junit-platform-engine', version: '1.1.5'
        testCompile group: 'org.spockframework', name: 'spock-core', version: '1.0-groovy-2.4'
        testCompile group: 'org.junit.jupiter', name: 'junit-jupiter-api', version: '5.0.0'
    }
}

subprojects {
    apply plugin: 'java'
    apply plugin: 'net.ltgt.apt'

    sourceCompatibility = 1.8
    targetCompatibility = 1.8
    tasks.withType(JavaCompile) {
        options.encoding = 'UTF-8'
    }

    test.useTestNG()
}

and here’s the pom of the failing module in question.

plugins {
    id "org.jetbrains.kotlin.jvm"
    id "net.ltgt.apt"
}
apply plugin: 'java'
apply plugin: 'kotlin'
apply plugin: 'net.ltgt.apt'
//apply plugin: 'org.inferred.processors'

group = 'com.company.blah.server.common'
description = 'description'
repositories {
    mavenLocal()
    maven {
        credentials {
            username 'user'
            password 'password'
        }
        url "http://blah/repository/maven-snapshots-group"
    }
}

dependencies {
    apt group: 'com.company.annotations', name: 'annotation-processors', version: '1.1.0'
    compile(group: 'com.company.blah.calculator', name: 'calculator-common', version: '0.1.0') {
        exclude(module: 'hibernate-jpa-2.0-api')
    }
    compile group: 'com.company.thirdparty.generated.stuff', name: 'stuff-cff11', version: '1.1'
    compile group: 'com.company.thirdparty.generated.stuff', name: 'stuff-mismo231', version: '2.3.1'

    compile group: 'com.datapublica.pg', name: 'hibernate-json', version: '0.4'
    compile group: 'com.fasterxml.jackson.core', name: 'jackson-annotations', version: '2.8.0'
    compile group: 'com.fasterxml.jackson.core', name: 'jackson-core', version: '2.8.9'
    compile group: 'com.fasterxml.jackson.datatype', name: 'jackson-datatype-jsr310', version: '2.8.9'
    compile group: 'com.fasterxml.jackson.dataformat', name: 'jackson-dataformat-xml', version: '2.8.9'
    compile group: 'com.fasterxml.jackson.module', name: 'jackson-module-parameter-names', version: '2.8.9'
    compile group: 'com.fasterxml.jackson.module', name: 'jackson-module-kotlin', version: '2.8.9'
    compile group: 'com.google.guava', name: 'guava', version: '19.0'
    compile group: 'org.jvnet.jaxb2_commons', name: 'jaxb2-basics', version: '0.6.4'
    compile group: 'org.reflections', name: 'reflections', version: '0.9.10'
    compile group: 'org.mapstruct', name: 'mapstruct-jdk8', version: '1.2.0-PromonTech'
    compile group: 'org.mapstruct', name: 'mapstruct-processor', version: '1.2.0-PromonTech'
    compile group: 'io.swagger', name: 'swagger-annotations', version: '1.5.10'
    compile group: 'javax.validation', name: 'validation-api', version: '1.1.0.Final'
    compile(group: 'org.apache.commons', name: 'commons-io', version: '1.3.2') {
        exclude(module: 'commons-logging')
    }
    compile(group: 'org.apache.commons', name: 'commons-lang3', version: '3.5') {
        exclude(module: 'commons-logging')
    }
    compile group: 'org.apache.velocity', name: 'velocity', version: '1.7'
    compile group: 'org.axonframework', name: 'axon-spring', version: '3.0.6'
    compile group: 'org.hibernate', name: 'hibernate-core', version: '5.2.5.Final'
    compile group: 'org.hibernate', name: 'hibernate-entitymanager', version: '5.2.5.Final'
    compile group: 'org.hibernate.common', name: 'hibernate-commons-annotations', version: '5.0.1.Final'
    compile group: 'org.joda', name: 'joda-money', version: '0.11'
    compile group: 'org.postgresql', name: 'postgresql', version: '9.4.1212.jre7'
    compile group: 'org.springframework.boot', name: 'spring-boot-starter-actuator', version: '1.5.6.RELEASE'
    compile group: 'org.springframework.boot', name: 'spring-boot-starter-data-jpa', version: '1.5.6.RELEASE'
    compile group: 'org.springframework.boot', name: 'spring-boot-starter-hateoas', version: '1.5.6.RELEASE'
    compile group: 'org.springframework.security', name: 'spring-security-core', version: '4.2.3.RELEASE'
    testCompile group: 'junit', name: 'junit', version: '4.12'
    compileOnly group: 'javax.servlet', name: 'javax.servlet-api', version: '3.1.0'
}

Update 20/11/17:

That error seemed to occur due to gradle not including optional dependencies per https://stackoverflow.com/a/26220205/1394698

I had to modify the pom of the annotation project in order for gradle to find Velocity, but I’m still having issues with gradle finding my annotation class @Id which is declared in my annotation-processor project. It manifests itself with this error for any class that attempts to include my Annotation

/Users/tylerthrailkill/Documents/dev/code/server/server-common/src/main/java/com/company/decision/common/WorkItemId.java:13: error: package com.company.annotations does not exist
import com.company.annotations.Id;
                                 ^
/Users/tylerthrailkill/Documents/dev/code/server/server-common/src/main/java/com/company/decision/common/WorkItemId.java:19: error: cannot find symbol
@Id
 ^
  symbol: class Id
3

When using net.ltgt.apt, I believe you need both:

apt group: 'com.company.annotations', name: 'annotation-processors', version: '1.1.0'
compileOnly group: 'com.company.annotations', name: 'annotation-processors', version: '1.1.0'

On the other hand, I believe the palantir plugin automatically adds anything from the configuration for the annotations to the compile classpath as well.

4

Fantastic! That worked! Thank you very much! Wonder why it wasn’t working with palantir’s plugin though :confused: