Java 文件序列化和反序列化

list序列化

 /*** 序列化* @param list* @param filename* @throws IOException*/public static void serializeList(List<Map<String, Object>> list, String filename) throws IOException {try (ObjectOutputStream oos = new ObjectOutputStream(new FileOutputStream(filename))) {oos.writeObject(list);}}/*** 反序列化* @param filename* @return* @throws IOException* @throws ClassNotFoundException*/public static List<Map<String, Object>> deserializeList(String filename) throws IOException, ClassNotFoundException {try (ObjectInputStream ois = new ObjectInputStream(new FileInputStream(filename))) {@SuppressWarnings("unchecked")List<Map<String, Object>> list = (List<Map<String, Object>>) ois.readObject();return list;}}/*** 查询数据** @return*/public List<Map<String, Object>> getdata() {JdbcTemplate jdbcTemplate2 = getJdbcTemplate2("jdbc:mysql://localhost:3306/gzw?serverTimezone=UTC", "root", "root");String sql = "select name,max(mon) from (\n" +"select name,lx,sum(money) mon from user GROUP BY name,lx order by name ) t1 GROUP BY name order by name ";List<Map<String, Object>> maps = jdbcTemplate2.queryForList(sql);return maps;}public List getLx() throws IOException, ClassNotFoundException {String name = "gzw.data"+sdf.format(new Date());//先判断有没有文件String dir = "E:\\test\\";File file = new File(dir + name);//有文件就用文件数据 -数据多久更新if (file.exists()) {List<Map<String, Object>> objects = deserializeList(dir + name);return objects;} else {//没有文件数据，查询sqlList<Map<String, Object>> getdata = getdata();//序列化，保存为文件serializeList(getdata, dir + name);return getdata;}}

 public static void serializeList(List<Object> list, String filename) throws IOException {try (ObjectOutputStream oos = new ObjectOutputStream(new FileOutputStream(filename))) {oos.writeObject(list);}}public static List<Object> deserializeList(String filename) throws IOException, ClassNotFoundException {try (ObjectInputStream ois = new ObjectInputStream(new FileInputStream(filename))) {@SuppressWarnings("unchecked")List<Object> list = (List<Object>) ois.readObject();return list;}}

map序列化

package com.dxy.util.xlh;import java.io.*;
import java.util.HashMap;
import java.util.Map;/*** Java序列化和反序列化 map*/
public class SerializeDeserializeMap {public static void serializeMap(Map<String, Object> map, String filename) throws IOException {try (ObjectOutputStream oos = new ObjectOutputStream(new FileOutputStream(filename))) {oos.writeObject(map);}}//@SuppressWarnings("unchecked")public static Map<String, Object> deserializeMap(String filename) throws IOException, ClassNotFoundException {try (ObjectInputStream ois = new ObjectInputStream(new FileInputStream(filename))) {return (Map<String, Object>) ois.readObject();}}public static void main(String[] args) {Map<String, Object> map = new HashMap<>();map.put("key1", "value1");map.put("key2", "value2");map.put("key3", 1);try {// 序列化serializeMap(map, "map.ser");// 反序列化Map<String, Object> deserializedMap = deserializeMap("map.ser");System.out.println(deserializedMap);} catch (IOException | ClassNotFoundException e) {e.printStackTrace();}}
}