1.List<Map<String,String>>的遍历:
Map<String,String> map = new HashMap<String, String>();
map.put("1", "fds");
map.put("2", "valu");
List<Map<String, String>> list = new ArrayList<Map<String, String>>();
list.add(map);
for (Map<String, String> m : list){
for (String k : m.keySet()){
System.out.println(k + " : " + m.get(k));
}
}
2.两个List<Map<String,String>>相互比较,有相同数据时某些字段相加减
inOrderList与outOrderList放自己的所比较的数据,name,number,id为map的key值
for (int i = 0; i < inOrderList.size(); i++) {//循环获取入库数据
String number1 = String.valueOf(inOrderList.get(i).get("number"));
String depotName1 = inOrderList.get(i).get("name");
String proId1 = inOrderList.get(i).get("id");
for (int j = 0; j < outOrderList.size(); j++) {//循环获取出库数据
String number2 = String.valueOf(outOrderList.get(j).get("number"));
String depotName2 = outOrderList.get(j).get("name");
String proId2 = outOrderList.get(j).get("id");
if (depotName1.equals(depotName2) && proId1.equals(proId2)) {
Integer sum =Integer.parseInt(number1) - Integer.parseInt(number2);//判断是否为同一条数据,同条数据数量相减
inOrderList.get(i).put("number", sum + "");
}
}
}
3.单个List<Map<String,String>>相互比较,相同数据相加(转)
List<Map<String, String>> l = new ArrayList<Map<String,String>>();
Map<String, String> m1 = new HashMap<String, String>();
m1.put("count", "1");
m1.put("name", "帮宝适纸尿裤L164 超薄干爽夏季透气专用婴儿尿不湿");
m1.put("province", "江苏省");
m1.put("date", "2014-09-23 10:13:39");
m1.put("channel", "东环大润发");
m1.put("city", "苏州市");
l.add(m1);
Map<String, String> m2 = new HashMap<String, String>();
m2.put("count", "1");
m2.put("name", "帮宝适纸尿裤L164 超薄干爽夏季透气专用婴儿尿不湿");
m2.put("province", "江苏省");
m2.put("date", "2014-09-23 10:13:39");
m2.put("channel", "东环大润发");
m2.put("city", "泰州市");
l.add(m2);
Map<String, String> m3 = new HashMap<String, String>();
m3.put("count", "1");
m3.put("name", "帮宝适纸尿裤L164 超薄干爽夏季透气专用婴儿尿不湿");
m3.put("province", "江苏省");
m3.put("date", "2014-09-23 10:13:39");
m3.put("channel", "东环大润发");
m3.put("city", "泰州市");
l.add(m3);
List<Map<String, String>> countList = new ArrayList<Map<String,String>>();//用于存放最后的结果
for (int i = 0; i < l.size(); i++) {
String count = l.get(i).get("count");
String name = l.get(i).get("name");
String province = l.get(i).get("province");
String date = l.get(i).get("date");
String channel = l.get(i).get("channel");
String city = l.get(i).get("city");
int flag = 0;//0为新增数据,1为增加count
for (int j = 0; j < countList.size(); j++) {
String count_ = countList.get(j).get("count");
String name_ = countList.get(j).get("name");
String province_ = countList.get(j).get("province");
String date_ = countList.get(j).get("date");
String channel_ = l.get(j).get("channel");
String city_ = countList.get(j).get("city");
if (count.equals(count_)&&
name.equals(name_)&&
province.equals(province_)&&
date.equals(date_)&&
channel.equals(channel_)&&
city.equals(city_)) {
int sum = Integer.parseInt(l.get(i).get("count")) + Integer.parseInt(countList.get(j).get("count"));
countList.get(j).put("count", sum + "");
flag = 1;
continue;
}
}
if (flag == 0) {
countList.add(l.get(i));
}
}
for (Map<String, String> map : countList) {
System.out.println(map);
}
}