export class Collections { public static stringArrayToStringSet(str: string[]): any { var hashSet = new java.util.HashSet(); if ("undefined" != typeof str) { for (var element in str) { hashSet.add('' + str[element]); } } return hashSet; } public static stringSetToStringArray(stringSet: any): string[] { var arr = []; if ("undefined" != typeof stringSet) { var it = stringSet.iterator(); while (it.hasNext()) { var element = '' + it.next(); arr.push(element); } } return arr; } }