IOException文件加载问题-Java/

Question

如何修复从文件加载ArrayList的问题？

完整代码在git上：项目github链接

当我从文件加载数据时，我会将其取回->IOException

我正在学习使用流，所以我正在将其写入文件。

程序结束后，我想在数组列表中写下用户到达的时间，并列出游戏完成的所有时间。

package sk.games.puzzle;
import java.io.*;
import java.util.*;
public class BestTimes implements Iterable<BestTimes.PlayerTime>, Serializable{
private static final String BESTTIME_DB = System.getProperty("user.home")
+ System.getProperty("file.separator")
+ "best.time";
private List<PlayerTime> playerTimes = new ArrayList<>();
public Iterator<PlayerTime> iterator() {
return playerTimes.iterator();
}
public void addTime(String name, int time){
playerTimes.add(new PlayerTime(name, time));
Collections.sort(playerTimes);
}
public void load(){
ObjectInputStream load = null;
try {
load = new ObjectInputStream(new FileInputStream(BESTTIME_DB));
playerTimes = (ArrayList<PlayerTime>) load.readObject();
} catch (FileNotFoundException e) {
System.err.println("fail nebola najdena db");
} catch (IOException e) {
System.err.println("fail nebola otvorena db");
} catch (ClassNotFoundException e) {
System.err.println("fail nebol najdeny zaznam");
} finally {
if (load != null) {
try {
load.close();
} catch (IOException e) {
//empty
}
}
}
}
public void save() {
ObjectOutputStream save = null;
try {
save = new ObjectOutputStream(new FileOutputStream(BESTTIME_DB));
save.writeObject(playerTimes);
} catch (FileNotFoundException e) {
System.err.println("fail db neexistuje");
} catch (IOException e) {
System.err.println("fail nepodarilo sa otvorit db");
} finally {
if (save != null) {
try {
save.close();
} catch (IOException e) {
//empty
}
}
}
}
@Override
public String toString() {
Formatter f = new Formatter();
for (int i = 0; i < playerTimes.size(); i++) {
PlayerTime pt = playerTimes.get(i);
f.format("%02d. %s - %ds.n", i, pt.getName(), pt.getTime());
}
return f.toString();
}
public static class PlayerTime implements Comparable<PlayerTime> {
private final String name;
private final int time;
public PlayerTime(String name, int time) {
this.name = name;
this.time = time;
}
public String getName() {
return name;
}
public int getTime() {
return time;
}
@Override
public int compareTo(PlayerTime o){
return Integer.compare(this.time, o.getTime());
}
}
}

Answer 1

问题是PlayerTime类不可序列化。

public static class PlayerTime implements Comparable<PlayerTime> { }

应该是

public static class PlayerTime implements Comparable<PlayerTime> implements Serializable { }

除非将BestTimes对象写入文件，否则不必使BestTimes可序列化。