无法序列化/反序列化 ArrayList [英] Cannot Serialize/Deserialize ArrayList
问题描述
我正在尝试序列化和反序列化一个包含对象的数组列表:
I'm trying to serialize and deserialize an array list with a object inside:
HairBirt param = new HairBirt();
param.setName("name");
param.setValue(2.3f);
HairBirt param2 = new HairBirt();
param2.setName("name2");
param2.setValue(2.4f);
ArrayList<HairBirt> list = new ArrayList<HairBirt>();
list.add(param);
list.add(param2);
ByteArrayOutputStream bos = null;
try {
bos = new ByteArrayOutputStream();
ObjectOutputStream obj_out = new ObjectOutputStream(bos);
obj_out.writeObject(list);
} catch (IOException e) {
e.printStackTrace();
}
String encoded = bos.toString();
try {
encoded = URLEncoder.encode(encoded, "UTF-8");
} catch (UnsupportedEncodingException e1) {
e1.printStackTrace();
}
System.out.print("The serialized output is: " + encoded);
//DECODE
ArrayList<HairBirt> paramDecoded;
String myParam = null;
try {
myParam = URLDecoder.decode(encoded, "UTF-8");
} catch (UnsupportedEncodingException e1) {
e1.printStackTrace();
}
System.out.println("Got parameters");
ByteArrayInputStream bis = new ByteArrayInputStream(myParam.getBytes());
try {
ObjectInputStream obj_in = new ObjectInputStream(bis);
paramDecoded = (ArrayList<HairBirt>) obj_in.readObject();
} catch (IOException e) {
e.printStackTrace();
} catch (ClassNotFoundException e) {
e.printStackTrace();
}
HairList 对象也是一个可序列化的对象.
The HairList object is also a serializable object.
此代码执行返回以下错误:
This code execution is returning the following error:
java.io.InvalidClassException: java.util.ArrayList;本地类不兼容:流 classdesc serialVersionUID = 8664875232659988799,本地类 serialVersionUID = 8683452581122892189
在行 paramDecoded = (ArrayList
我不知道我做错了什么.能给点建议吗?
I don't know what i'm doing wrong. Can you give a tip?
更新:
已解决:只是使用了本机的 HairBirt 数组而不是 ArrayList 并且它可以工作:
Resolved: Just used a native array of HairBirt instead of a ArrayList and it works:
HairBirt[] list = new HairBirt[x];
代替
ArrayList<HairBirt> list = new ArrayList<HairBirt>();
感谢大家的帮助.
推荐答案
不要使用 ByteArrayOutputStream.toString()
- 而是使用 toByteArray()
和 base64-编码该二进制数据以将其转换为字符串而不会丢失信息.
Don't use ByteArrayOutputStream.toString()
- instead, use toByteArray()
and base64-encode that binary data to convert it into a string without losing information.
我强烈怀疑这是主要问题 - 您在序列化后丢失了数据.您可能还应该关闭或至少刷新 ObjectOutputStream
.我不知道在这种情况下这是否真的有用,但这似乎是个好主意.
I strongly suspect that's the main problem - that you were losing the data after serialization. You should probably also close or at least flush the ObjectOutputStream
. I don't know offhand whether that actually does anything in this case, but it would seem to be a good idea.
我不相信 Java 中直接有任何 base64 支持(无论如何在公共类中),但是您可以使用各种 3rd 方库,例如 Apache Commons Codec 库中的那个.
I don't believe there's any base64 support directly in Java (in a public class, anyway) but there are various 3rd party libraries you can use, such as the one in the Apache Commons Codec library.
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