Here you can find the source of copyParameters(Map
static Map<String, Object> copyParameters(Map<String, Object> parameters)
//package com.java2s; //License from project: Apache License import java.util.HashMap; import java.util.Map; public class Main { static Map<String, Object> copyParameters(Map<String, Object> parameters) { Map<String, Object> ps = new HashMap<>(); if (parameters != null) ps.putAll(parameters);//w w w .ja v a2 s . com return ps; } }