List 转 String 和 String[] 的方法

public class List2StringUtils {

/**
 * 将 List 转成 String
 * @param list List<String>
 * @return String 字符串
 */
public static String listToString(List<String> list) {
    StringBuilder builder = new StringBuilder();
    String resultString;
    boolean flag = false;
    for (String str : list) {
        if (flag) {
            builder.append(",");
        } else {
            flag = true;
        }
        builder.append(str);
    }
    resultString = builder.toString();
    return resultString;
}

/**
 * 将 List 转换成 String[]
 * @param list List<String>
 * @return String[] 数组
 */
public static String[] listToArray(List<String> list) {
    String[] strings = new String[list.size()];
    for (int i = 0; i < list.size(); i++) {
        strings[i] = list.get(i);
    }
    return strings;
}

}