利用apache的commons对list重新排序,apachecommonslist
利用apache的commons对list重新排序,apachecommonslist
主要是apache-commons-beanutils-1.8.3.jar、collections、logging包
public void sortList(){
List<Map<String, String>> sjzList = new ArrayList<Map<String, String>>();
Map<String, String> map1 = new HashMap<String, String>();
map1.put("TIME", "20160225");
map1.put("CONTENT", "测试内容2");
Map<String, String> map2 = new HashMap<String, String>();
map2.put("TIME", "20160225");
map2.put("CONTENT", "测试内容1");
Map<String, String> map3 = new HashMap<String, String>();
map3.put("TIME", "20160223");
map3.put("CONTENT", "测试内容3");
sjzList.add(map1);
sjzList.add(map2);
sjzList.add(map3);
for (Map<String, String> map : sjzList) {
System.out.println("排序前:"+map.get("TIME")+":"+map.get("CONTENT"));
}
Comparator mycmp1 = ComparableComparator.getInstance();
mycmp1 = ComparatorUtils.reversedComparator(mycmp1); //逆序
mycmp1 = ComparatorUtils.nullHighComparator(mycmp1); // 允许null
Comparator mycmp2 = ComparableComparator.getInstance();
mycmp2 = ComparatorUtils.nullHighComparator(mycmp2); // 允许null
// 声明要排序的对象的属性,并指明所使用的排序规则,如果不指明,则用默认排序
ArrayList<Object> sortFields = new ArrayList<Object>();
sortFields.add(new BeanComparator("TIME", mycmp1)); // 主排序(第一排序)
sortFields.add(new BeanComparator("CONTENT", mycmp2)); // 次排序(第二排序)
// 创建一个排序链
ComparatorChain multiSort = new ComparatorChain(sortFields);
// 开始真正的排序,按照先主,后副的规则
Collections.sort(sjzList, multiSort);
System.out.println("------分割线----------");
for (Map<String, String> map : sjzList) {
System.out.println("排序后:"+map.get("TIME")+":"+map.get("CONTENT"));
}
}
输出结果:
排序前:20160225:测试内容2
排序前:20160225:测试内容1
排序前:20160223:测试内容3
------分割线----------
排序后:20160225:测试内容1
排序后:20160225:测试内容2
排序后:20160223:测试内容3
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