也许我缺少了一些东西，但是为什么不只使用jenkins类路径中已经存在的标准Java库呢？

import java.io.BufferedReader
import java.io.InputStreamReader
import java.io.OutputStreamWriter
import java.net.URL
import java.net.URLConnection

def sendPostRequest(urlString, paramString) {
    def url = new URL(urlString)
    def conn = url.openConnection()
    conn.setDoOutput(true)
    def writer = new OutputStreamWriter(conn.getOutputStream())

    writer.write(paramString)
    writer.flush()
    String line
    def reader = new BufferedReader(new     InputStreamReader(conn.getInputStream()))
    while ((line = reader.readLine()) != null) {
      println line
    }
    writer.close()
    reader.close()
}

sendPostRequest("http://www.something.com", "param1=abc&param2=def")