blocks|key|1755662|text|MyClass2只是一个接口，所以从技术上讲，它没有属性，只有方法。也就是说，如果您的实例变量本身是不可序列化的，我所知道的唯一解决方法就是将这些字段声明为瞬态的。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1755663|例如：|1755664|private+transient+Foo+foo;|code-block|syntax|javascript|1755665|当您声明一个字段是瞬态的时，它将在序列化和反序列化过程中被忽略。请记住，当您使用瞬态字段反序列化一个对象时，该字段的值将始终是它的默认值(通常为空)。|1755666|注您还可以重写类的readResolve()方法，以便基于其他系统状态初始化瞬态字段。|1755667|entityMap^0|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|O|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|P|8|@]|9|@]|A|$]]|$1|D|3|E|5|F|7|Q|8|@]|9|@]|A|$G|H]]|$1|I|3|J|5|6|7|R|8|@]|9|@]|A|$]]|$1|K|3|L|5|6|7|S|8|@]|9|@]|A|$]]|$1|M|3|-4|5|6|7|T|8|@]|9|@]|A|$]]]|N|$]]

MyClass2 is just an interface so techinicaly it has no properties, only methods. That being said if you have instance variables that are themselves not serializeable the only way I know of to get around it is to declare those fields transient.

ex:

<pre><code>private transient Foo foo;
</code></pre>

When you declare a field transient it will be ignored during the serialization and deserialization process. Keep in mind that when you deserialize an object with a transient field that field's value will always be it's default (usually null.)

Note you can also override the readResolve() method of your class in order to initialize transient fields based on other system state.

blocks|key|1540812|text|如果您可以修改MyClass2，则解决此问题的最简单方法是将属性声明为瞬态。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1540813|entityMap^0|0^^$0|@$1|2|3|4|5|6|7|D|8|@]|9|@]|A|$]]|$1|B|3|-4|5|6|7|E|8|@]|9|@]|A|$]]]|C|$]]

If you can modify MyClass2, the easiest way to address this is declare the property transient.

blocks|key|1540861|text|XStream是一个很棒的库，可以对任何对象进行快速的Java序列化，无论它是否可序列化。即使XML目标格式不适合您，您也可以使用源代码来学习如何使用它。|type|unstyled|depth|inlineStyleRanges|entityRanges|offset|length|data|1540862|entityMap|0|LINK|mutability|MUTABLE|url|http://x-stream.github.io/^0|0|7|0|0^^$0|@$1|2|3|4|5|6|7|L|8|@]|9|@$A|M|B|N|1|O]]|C|$]]|$1|D|3|-4|5|6|7|P|8|@]|9|@]|C|$]]]|E|$F|$5|G|H|I|C|$J|K]]]]

<a href="http://x-stream.github.io" rel="nofollow noreferrer">XStream</a> is a great library for doing fast Java to XML serialization for any object no matter if it is Serializable or not. Even if the XML target format doesn't suit you, you can use the source code to learn how to do it.

blocks|key|1755783|text|取决于为什么MyClass2的该成员是不可序列化的。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1755784|如果有一些很好的理由来解释为什么MyClass2不能以序列化的形式表示，那么很可能同样的原因也适用于MyClass，因为它是一个子类。|1755785|可以通过实现readObject和writeObject来为MyClass编写自定义的序列化形式，这样就可以从序列化的数据中适当地重新创建MyClass中的MyClass2实例数据的状态。如果MyClass2的API是固定的，而你不能添加Serializable，那么就应该这样做。|1755786|但是首先你应该弄清楚为什么MyClass2是不可序列化的，也许可以改变它。|1755787|entityMap^0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|J|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|K|8|@]|9|@]|A|$]]|$1|D|3|E|5|6|7|L|8|@]|9|@]|A|$]]|$1|F|3|G|5|6|7|M|8|@]|9|@]|A|$]]|$1|H|3|-4|5|6|7|N|8|@]|9|@]|A|$]]]|I|$]]

Depends why that member of MyClass2 isn't serializable.

If there's some good reason why MyClass2 can't be represented in a serialized form, then chances are good the same reason applies to MyClass, since it's a subclass.

It may be possible to write a custom serialized form for MyClass by implementing readObject and writeObject, in such a way that the state of the MyClass2 instance data in MyClass can be suitably recreated from the serialized data. This would be the way to go if MyClass2's API is fixed and you can't add Serializable.

But first you should figure out why MyClass2 isn't serializable, and maybe change it.

blocks|key|1540983|text|序列化不可序列化类的实例(或至少是的子类)的一种有用的方法是串行代理。从本质上讲，您实现writeReplace是为了返回一个完全不同的可序列化类的实例，该类实现了readResolve以返回原始对象的副本。我写了一个在Usenet上序列化java.awt.BasicStroke的例子|type|unstyled|depth|inlineStyleRanges|entityRanges|offset|length|data|1540984|entityMap|0|LINK|mutability|MUTABLE|url|http://groups.google.com/group/comp.lang.java.programmer/msg/820a7343ae7713a6^0|32|6|0|0^^$0|@$1|2|3|4|5|6|7|L|8|@]|9|@$A|M|B|N|1|O]]|C|$]]|$1|D|3|-4|5|6|7|P|8|@]|9|@]|C|$]]]|E|$F|$5|G|H|I|C|$J|K]]]]

A useful approach for serialising instances of non-serializable classes (or at least subclasses of) is known a Serial Proxy. Essentially you implement writeReplace to return an instance of a completely different serializable class which implements readResolve to return a copy of the original object. I wrote an example of serialising java.awt.BasicStroke on <a href="http://groups.google.com/group/comp.lang.java.programmer/msg/820a7343ae7713a6" rel="nofollow noreferrer">Usenet</a>

blocks|key|1755983|text|如果可能，可以将非序列化部分设置为瞬态部分。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1755984|private+transient+SomeClass+myClz;|code-block|syntax|javascript|1755985|否则，您可以使用Kryo。Kryo是一个快速高效的Java对象图序列化框架(例如，java.awt.Color的JAVA序列化需要170个字节，Kryo只需要4个字节)，它也可以序列化不可序列化的对象。Kryo还可以执行自动的深层和浅层复制/克隆。这是从对象到对象的直接复制，而不是object->bytes->object。|offset|length|style|CODE|1755986|下面是一个如何使用kryo的示例|1755987|Kryo+kryo+=+new+Kryo();
//+####+Store+to+disk...
Output+output+=+new+Output(new+FileOutputStream("file.bin"));
SomeClass+someObject+=+...
kryo.writeObject(output,+someObject);
output.close();
//+###+Restore+from+disk...
Input+input+=+new+Input(new+FileInputStream("file.bin"));
SomeClass+someObject+=+kryo.readObject(input,+SomeClass.class);
input.close();|1755988|序列化的对象也可以通过注册精确的序列化程序来压缩：|1755989|kryo.register(SomeObject.class,+new+DeflateCompressor(new+FieldSerializer(kryo,+SomeObject.class)));|1755990|entityMap|0|LINK|mutability|MUTABLE|url|https://github.com/EsotericSoftware/kryo^0|0|0|3X|L|8|4|0|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|12|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|13|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|14|8|@$I|15|J|16|K|L]]|9|@$I|17|J|18|1|19]]|A|$]]|$1|M|3|N|5|6|7|1A|8|@]|9|@]|A|$]]|$1|O|3|P|5|D|7|1B|8|@]|9|@]|A|$E|F]]|$1|Q|3|R|5|6|7|1C|8|@]|9|@]|A|$]]|$1|S|3|T|5|D|7|1D|8|@]|9|@]|A|$E|F]]|$1|U|3|-4|5|6|7|1E|8|@]|9|@]|A|$]]]|V|$W|$5|X|Y|Z|A|$10|11]]]]

If possible, the non-serialiable parts can be set as transient

<pre><code>private transient SomeClass myClz;
</code></pre>

Otherwise you can use <a href="https://github.com/EsotericSoftware/kryo" rel="nofollow">Kryo</a>. Kryo is a fast and efficient object graph serialization framework for Java (e.g. JAVA serialization of java.awt.Color requires 170 bytes, Kryo only 4 bytes), which can serialize also non serializable objects. Kryo can also perform automatic deep and shallow copying/cloning. This is direct copying from object to object, not <code>object-&gt;bytes-&gt;object</code>.

Here is an example how to use kryo

<pre><code>Kryo kryo = new Kryo();
// #### Store to disk...
Output output = new Output(new FileOutputStream("file.bin"));
SomeClass someObject = ...
kryo.writeObject(output, someObject);
output.close();
// ### Restore from disk...
Input input = new Input(new FileInputStream("file.bin"));
SomeClass someObject = kryo.readObject(input, SomeClass.class);
input.close();
</code></pre>

Serialized objects can be also compressed by registering exact serializer:

<pre><code>kryo.register(SomeObject.class, new DeflateCompressor(new FieldSerializer(kryo, SomeObject.class)));
</code></pre>

I have:

<pre><code>class MyClass extends MyClass2 implements Serializable {
 //...
}
</code></pre>

In MyClass2 is a property that is not serializable. How can I serialize (and de-serialize) this object?

Correction: MyClass2 is, of course, not an interface but a class.

Java Serialization with non serializable parts

我有：class MyClass extends MyClass2 implements Serializable {  //...}在MyClass2中是一个不可序列化的属性。我如何序列化(和反序列化)这个对象？更正: MyClass2当然不是一个接口，而是一个类。

问使用不可序列化部分的Java序列化
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