Here you can find the source of toStringArray(final List
public static <E> String[] toStringArray(final List<E> list)
//package com.java2s; //License from project: Open Source License import java.util.*; public class Main { public static <E> String[] toStringArray(final List<E> list) { return toStringArray(list, null); }//from w ww .j a v a 2s. c o m public static <E> String[] toStringArray(final List<E> list, String defaultValue) { String[] array = null; if (list != null) { array = new String[list.size()]; for (int i = 0; i < list.size(); i++) { if (list.get(i) != null) { array[i] = list.get(i).toString(); } else { array[i] = defaultValue; } } } return array; } public static <E> String toString(final List<E> list) { return toString(list, "\t"); } public static <E> String toString(final List<E> list, String separator) { StringBuilder sb = new StringBuilder(); if (list != null && list.size() > 0) { for (int i = 0; i < list.size() - 1; i++) { if (list.get(i) != null) { sb.append(list.get(i).toString()).append(separator); } else { sb.append("null").append(separator); } } if (list.get(list.size() - 1) != null) { sb.append(list.get(list.size() - 1).toString()); } else { sb.append("null"); } } return sb.toString(); } }