updateJenkinsJobJDK.groovy

// this script can be used to change the JDK for multiple Jenkins Jobs
// to use the script, edit the variables and run it in the Jenkins Script Console

// please set the variable value
def jobNameWithCorrectJdk = ""      // set a JobName with the correct JDK
def jdkToChange = "JDK[JDK 1.8]"    // set the JDK you want to change
def partOfJobNameToSearch = ""      // set a part of the job name to generate the list of jobs

// script - here you have nothing to edit
def newJdk = Jenkins.instance.getItemByFullName(jobNameWithCorrectJdk).JDK
def totCounter = 0
def okCounter = 0
def badCounter = 0
for (item in Jenkins.instance.items) {
  name = item.name
  if (name.toLowerCase().contains(partOfJobNameToSearch.toLowerCase())) {
    totCounter++
    println("---------------------------------")
    if (item.getJDK().toString().contains(jdkToChange)) {
      println("[INFO] change JDK: " + item.name)
      println("--> old JDK: " + item.getJDK())
      item.setJDK(newJdk)
      if (item.getJDK().toString().contains(newJdk.toString())) {
        println("JDK change successful")
        okCounter++
      } else {
        println("[ERROR] JDK change not successful:")
        println("--> " + item.name)
        println("--> " + item.getJDK())
        badCounter++
      }
    } else {
      println("[INFO] no JDK change required: " + item.name)
    }
  }
}
println("---------------------------------")
println(totCounter + " total items")
println(okCounter + " items with status successful  :)")
println(badCounter + " items with status failure     :(")
println((totCounter - badCounter - okCounter) + " items with no change")