java

 import jenkins.model.Jenkins
 import hudson.model.Job
 import jenkins.model.BuildDiscarderProperty
 import hudson.tasks.LogRotator
 // 遍历所有的任务
 Jenkins.instance.allItems(Job).each { job ->
     if ( job.isBuildable() && job.supportsLogRotator() && job.getProperty(BuildDiscarderProperty) == null) {
         println " \"${job.fullDisplayName}\" 处理中"

         job.addProperty(new BuildDiscarderProperty(new LogRotator (2, 10, 2, 10)))
         println "$job.name 已更新"
     }
 }
 return;

 /**
 LogRotator构造参数分别为：
 daysToKeep:  If not -1, history is only kept up to this days.
 numToKeep: If not -1, only this number of build logs are kept.
 artifactDaysToKeep: If not -1 nor null, artifacts are only kept up to this days.
 artifactNumToKeep: If not -1 nor null, only this number of builds have their artifacts kept.
 **/

java

public void addProperty(JobProperty<? super JobT> jobProp) throws IOException {
    ((JobProperty)jobProp).setOwner(this);
    properties.add(jobProp);
    save();
}