List<Map<String, Object>>增删改查

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List<Map<String, Object>> List集合新增列

则需要：

List<Map<String, Object>> list_new = new ArrayList<Map<String, Object>>();//新建list集合对象，用于存储新的数据for (Map<String, Object> map : list) {//list为数据库查询出来的数据　　Long jxjhid=Long.valueOf(map.get("jxjhid").toString());　　//上面的是获取jxjh的值　　String mc_new="";　　if(jxjhid==1){　　　　mc_new="计划";　　}else{　　　　mc_new="不计划";　　}　　　　map.put("sfjh", mc_new);　　list_new .add(map);}//另外一种方式//不要下面两行代码

List<Map<String, Object>> list_new = new ArrayList<Map<String, Object>>();　　list_new .add(map);

List<Map<String, Object>> List集合删除map中的某个元素

List<Map<String, Object>> list_new = new ArrayList<Map<String, Object>>();Map<String, Object> map1=new HashMap<String, Object>();map1.put("ks", "01");map1.put("js", "10");list_new.add(map1);Map<String, Object> map2=new HashMap<String, Object>();map2.put("ks", "01");map2.put("js", "10");list_new.add(map2);for (Map<String, Object> map : list_new) {    map.remove("js");}

List<Map<String, Object>> List集合修改map中的元素

List<Map<String, Object>> list_new = new ArrayList<Map<String, Object>>();Map<String, Object> map1=new HashMap<String, Object>();map1.put("ks", "01");map1.put("js", "10");list_new.add(map1);Map<String, Object> map2=new HashMap<String, Object>();map2.put("ks", "01");map2.put("js", "10");list_new.add(map2);for (Map<String, Object> map : list_new) {    map.put("js","11");}

List<Map<String, Object>> List集合查询数据库数据

//公司wh框架的使用方法String sql="select * from jxap " //  + " left outer join (select jxjhid,ks from jxjh) jxjh on jxjh.jxjhid=jxap.jxjhid"    + " where jxap.jlztm=51 and jxap.bjid=:bjid and jxap.jxjhid in(select jxjhid from jxjh where xqm=:xqm )";SqlCommandImpl sci=new SqlCommandImpl(sql);sci.setInt("bjid", bjid);sci.setInt("xqm", xqm);List<Map<String, Object>> list=gdba.selectAsMapList(sci,jxap);

//普通的框架List<Map<String, Object>> list = new ArrayList<Map<String, Object>>();　// 关闭连接flagboolean colseFlag = false;  // 打开DB链接if (this.connection == null) {  this.connection = this.getDbConnection();  colseFlag = true;}PreparedStatement preStat = null;preStat = this.connection.prepareStatement(sql);ResultSet rs = null;Map<String, Object> map = null;rs = preStat.executeQuery();  // 生成ResultSetMetaDataResultSetMetaData rsMeta = preStat.getMetaData();while (rs.next()) {   map = this.Result2Map(rs, rsMeta);   // 追加到list中   list.add(map);  }

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