<dependency>

     <groupId>com.google.guava</groupId>

     <artifactId>guava</artifactId>

     <version>18.0</version>

 </dependency>

 package xxxxxx;

 import java.util.ArrayList;

 import java.util.HashMap;

 import java.util.List;

 import java.util.Map;

 import org.apache.commons.lang.StringUtils;

 import com.google.common.base.Function;

 import com.google.common.collect.ArrayListMultimap;

 import com.google.common.collect.ListMultimap;

 public class ListUtils {

     /**

      * list 中有一个为主键key

      *

      * @param list

      * @param function

      * @return

      */

     public static <K, V> Map<K, V> listToMap(List<V> list, Function<V, K> function) {

         Map<K, V> map = new HashMap<K, V>();

         if (list == null)

             return map;

         for (V value : list) {

             K k = function.apply(value);

             map.put(k, value);

         }

         return map;

     }

     /**

      * list 元素转为另一个元素的list

      */

     public static <F, R> List<R> listConvert(List<F> list, Function<F, R> function) {

         List<R> listN = new ArrayList<R>();

         if (list == null)

             return listN;

         for (F value : list) {

             R r = function.apply(value);

             if (r != null)

                 listN.add(r);

         }

         return listN;

     }

     /**

      * list 元素过滤另一个元素的list

      */

     public static <F> List<F> filter(List<F> list, Function<F, Boolean> function) {

         List<F> listN = new ArrayList<F>();

         if (list == null)

             return listN;

         for (F value : list) {

             Boolean r = function.apply(value);

             if (r)

                 listN.add(value);

         }

         return listN;

     }

     /**

      * list 元素转为另一个元素的list并且去重,适合list数据量较小

      */

     public static <F, R> List<R> listConvertAndUnique(List<F> list, Function<F, R> function) {

         List<R> listN = new ArrayList<R>();

         if (list == null)

             return listN;

         for (F value : list) {

             R r = function.apply(value);

             if (r != null && !listN.contains(r))

                 listN.add(r);

         }

         return listN;

     }

     /**

      * list 元素转为以seg分割的字符串

      */

     public static String split(List list, String seg) {

         StringBuilder sb = new StringBuilder();

         for (Object value : list) {

             sb.append(value.toString() + seg);

         }

         String t = sb.toString();

         if (t.endsWith(seg)) {

             int end = t.length() - seg.length();

             t = t.substring(0, end);

         }

         return t;

     }

     public static <V> Map<Integer, V> listToMapByHashCode(List<V> list) {

         Map<Integer, V> map = new HashMap<Integer, V>();

         for (V value : list) {

             map.put(Integer.valueOf(value.hashCode()), value);

         }

         return map;

     }

     public static <K, V> Map<K, V> listToMapByFunction(List<V> list,Function<V,K> function) {

         Map<K, V> map = new HashMap<K, V>();

         for (V value : list) {

             map.put(function.apply(value), value);

         }

         return map;

     }

     // list to ListMultimap

     public static <K, V> ListMultimap<K, V> listToListMultiMap(List<V> list, Function<V, K> function) {

         ListMultimap listMultimap = ArrayListMultimap.<K, V> create();

         for (V value : list) {

             listMultimap.put(function.apply(value), value);

         }

         return listMultimap;

     }

     public static <V> List<V> pageList(List<V> list, int pageIndex, int pageNum) {

         int size = list.size();

         int fromIndex = pageIndex * pageNum;

         if (fromIndex > size) {

             fromIndex = size;

         }

         int toIndex = fromIndex + pageNum;

         if (toIndex > size) {

             toIndex = size;

             return list.subList(fromIndex, toIndex);

         }

         return list.subList(fromIndex, toIndex);

     }

     public static <E> boolean isEmpty(List<E> list) {

         return list == null || list.isEmpty();

     }

     public static List<String> list(String s, String spe) {

         ArrayList<String> list = new ArrayList<>();

         if (StringUtils.isBlank(s))

             return list;

         String[] e = s.split(spe);

         for (String i : e) {

             list.add(i);

         }

         return list;

     }

     public static <T> List<T> toList(T... a) {

         if (a == null)

             return null;

         List<T> l = new ArrayList<>();

         for (T e : a) {

             l.add(e);

         }

         return l;

     }

     /**

      * 通过某个字段进行排序

      */

     public static <K, V> List<V> sortList(List<V> list) {

         return null;

     }

 }

 List<UserAccountDto> maList = null; //实际不能辅助为null，应该获取一个list实例

 List<TopMobileAccountVo> mavoList = ListUtils.listConvert(maList,new Function<UserAccountDto, TopMobileAccountVo>() {

     public TopMobileAccountVo apply(UserAccountDto ma) {

         TopMobileAccountVo vo = new TopMobileAccountVo();

         vo.convertPOToVO(ma);

         return vo;

     }

 });