Where can I find org.jenkinsci.plugins.workflow.steps.FlowInterruptedException with gradle?

The 'org.jenkins-ci.plugins.workflow:workflow-step-api:2.13' dependency has a POM that has this in it (taken from here):

<packaging>hpi</packaging>

The dependency that Gradle retrieves is the hpi artifact, not the jar one when you point at this dependency. This can be shown with a task like the following:

tasks.create('showDependencies') {
  doFirst {
    final config = configurations.getByName(sourceSets.getByName('main').compileClasspathConfigurationName)
    config.resolvedConfiguration.resolvedArtifacts.findAll { it.moduleVersion.id.group.contains('jenkins') }.each {
      println("Resolved dependency: id=${it.id}, extension=${it.extension}, classifier=${it.classifier}")
    }
  }
}

The output:

 > Task :showDependencies
Resolved dependency: id=jenkins-core.jar (org.jenkins-ci.main:jenkins-core:2.76), extension=jar, classifier=null
Resolved dependency: id=workflow-step-api.hpi (org.jenkins-ci.plugins.workflow:workflow-step-api:2.13), extension=hpi, classifier=null
Resolved dependency: id=cli.jar (org.jenkins-ci.main:cli:2.76), extension=jar, classifier=null
Resolved dependency: id=trilead-ssh2.jar (org.jenkins-ci:trilead-ssh2:build-217-jenkins-11), extension=jar, classifier=null
Resolved dependency: id=icon-set.jar (org.jenkins-ci.plugins.icon-shim:icon-set:1.0.5), extension=jar, classifier=null
Resolved dependency: id=remoting.jar (org.jenkins-ci.main:remoting:3.11), extension=jar, classifier=null
Resolved dependency: id=version-number.jar (org.jenkins-ci:version-number:1.4), extension=jar, classifier=null
Resolved dependency: id=crypto-util.jar (org.jenkins-ci:crypto-util:1.1), extension=jar, classifier=null
Resolved dependency: id=bytecode-compatibility-transformer.jar (org.jenkins-ci:bytecode-compatibility-transformer:1.8), extension=jar, classifier=null
Resolved dependency: id=structs.hpi (org.jenkins-ci.plugins:structs:1.5), extension=hpi, classifier=null
Resolved dependency: id=symbol-annotation.jar (org.jenkins-ci:symbol-annotation:1.5), extension=jar, classifier=null
Resolved dependency: id=annotation-indexer.jar (org.jenkins-ci:annotation-indexer:1.12), extension=jar, classifier=null
Resolved dependency: id=task-reactor.jar (org.jenkins-ci:task-reactor:1.4), extension=jar, classifier=null
Resolved dependency: id=commons-jelly.jar (org.jenkins-ci:commons-jelly:1.1-jenkins-20120928), extension=jar, classifier=null
Resolved dependency: id=commons-jexl.jar (org.jenkins-ci:commons-jexl:1.1-jenkins-20111212), extension=jar, classifier=null
Resolved dependency: id=memory-monitor.jar (org.jenkins-ci:memory-monitor:1.9), extension=jar, classifier=null
Resolved dependency: id=jmdns.jar (org.jenkins-ci:jmdns:3.4.0-jenkins-3), extension=jar, classifier=null
Resolved dependency: id=constant-pool-scanner.jar (org.jenkins-ci:constant-pool-scanner:1.2), extension=jar, classifier=null
Resolved dependency: id=dom4j.jar (org.jenkins-ci.dom4j:dom4j:1.6.1-jenkins-4), extension=jar, classifier=null

There are several ways to use Gradle's dependency management features to better handle dependencies. One possible way to change the dependency would be to add an artifact dependency with the extension. This may not solve your exact use case depending on how you want your dependencies to end up, but can hopefully point you in a direction:

compile(group: 'org.jenkins-ci.plugins.workflow', name: 'workflow-step-api', version: '2.13') {
  artifact {
    name = 'workflow-step-api'
    type = 'jar'
  }
}

As a side note, in the Jenkins plugin ecosystem, the Jenkins Maven HPI Plugin and Jenkins Plugin Parent POM work together to do dependency management so you don't run into issues like this.

Apparently I needed to add ext jar. Here is my build file

apply plugin: 'groovy'
apply plugin: 'idea'
apply plugin: 'java'
repositories {
    mavenCentral()
    maven {
        url 'https://repo.jenkins-ci.org/releases'
    }
    maven {
        url 'https://repo.jenkins-ci.org/public'
    }

}
sourceSets {
    main {
        groovy {
            srcDirs = ['src']
        }
    }
    test {
        groovy {
            srcDirs = ['test']
        }
    }
}
dependencies {
    compile group: 'org.jenkins-ci.main', name: 'jenkins-core', version: '2.76'
    compile group: 'org.jenkins-ci.plugins.workflow', name: 'workflow-step-api', version: '2.13', ext: 'jar'
    compile 'com.cloudbees:groovy-cps:1.14'
    compile 'org.codehaus.groovy:groovy-all:2.4.8'
    compileOnly 'javax.servlet:javax.servlet-api:3.1.0'
    testCompile 'junit:junit:4.12'
}