动机：

为了帮助进行远程调试(Java),能够请求远程服务器将任意对象发送到我的本地计算机进行检查很有用.但是,这意味着远程服务器必须能够序列化运行时预先未知的任意java对象.

所以我问了一下,偶然发现了Kryo serialization library.从Kryo’s documentation开始,一个主要功能是在序列化任意Java对象方面非常强大.对象不必实现Serializable,也不需要no-arg构造函数进行反序列化,并且我什至不需要在序列化之前了解有关对象结构的任何知识.完善！

问题：

因此,为了测试Kryo,我尝试查看是否可以序列化然后反序列化PrintWriter对象(即任意对象)：

import com.esotericsoftware.kryo.Kryo;

import com.esotericsoftware.kryo.io.Input;

import com.esotericsoftware.kryo.io.Output;

import java.io.*;

public class SerializationTest {

private static final String ioFileName = "someIO.bin";

public static void main(String[] args) {

// Create a PrintWriter object that I will later attempt to serialize

PrintWriter outObj = null;

try {

outObj = new PrintWriter("textfile.txt");

} catch (FileNotFoundException e) {

e.printStackTrace();

}

// Change the PrintWriter's state as a test for later to see if state is restored after serialization and deserialization

outObj.println("Hello"); // "Hello" held in PrintWriter's buffer

Kryo kryo = new Kryo(); // Initialize Kryo serialization

writeObj(kryo, outObj); // Save PrintWriter object to file with "Hello" still in its buffer

// Read the previously saved Printwriter object (still with "Hello" in its buffer)

PrintWriter inObj = (PrintWriter) readObj(kryo);

inObj.close(); // commit "Hello" to disk (using deserialized object)

outObj.close(); // commit "Hello" to disk (using original object)

System.out.println(inObj);

}

public static Object readObj(Kryo kryo) {

Object obj = null;

try {

Input input = new Input(new FileInputStream(ioFileName));

obj = kryo.readClassAndObject(input); // ERROR HERE!!

input.close();

} catch (FileNotFoundException e) {

e.printStackTrace();

}

return obj;

}

public static void writeObj(Kryo kryo, Object obj) {

try {

Output output = new Output(new FileOutputStream(ioFileName));

kryo.writeClassAndObject(output, obj);

output.close();

} catch (FileNotFoundException e) {

e.printStackTrace();

}

}

}

序列化工作正常,但是反序列化后,对第39行的kryo.readClassAndObject(input)的调用给出了以下IllegalAccessError：

Exception in thread "main" java.lang.IllegalAccessError: tried to access class sun.nio.cs.UTF_8 from class sun.nio.cs.UTF_8ConstructorAccess

at sun.nio.cs.UTF_8ConstructorAccess.newInstance(Unknown Source)

at com.esotericsoftware.kryo.Kryo$DefaultInstantiatorStrategy$1.newInstance(Kryo.java:1234)

at com.esotericsoftware.kryo.Kryo.newInstance(Kryo.java:1086)

at com.esotericsoftware.kryo.serializers.FieldSerializer.create(FieldSerializer.java:547)

at com.esotericsoftware.kryo.serializers.FieldSerializer.read(FieldSerializer.java:523)

at com.esotericsoftware.kryo.Kryo.readObject(Kryo.java:704)

at com.esotericsoftware.kryo.serializers.ObjectField.read(ObjectField.java:106)

at com.esotericsoftware.kryo.serializers.FieldSerializer.read(FieldSerializer.java:528)

at com.esotericsoftware.kryo.Kryo.readObject(Kryo.java:704)

at com.esotericsoftware.kryo.serializers.ObjectField.read(ObjectField.java:106)

at com.esotericsoftware.kryo.serializers.FieldSerializer.read(FieldSerializer.java:528)

at com.esotericsoftware.kryo.Kryo.readObject(Kryo.java:704)

at com.esotericsoftware.kryo.serializers.ObjectField.read(ObjectField.java:106)

at com.esotericsoftware.kryo.serializers.FieldSerializer.read(FieldSerializer.java:528)

at com.esotericsoftware.kryo.Kryo.readObject(Kryo.java:704)

at com.esotericsoftware.kryo.serializers.ObjectField.read(ObjectField.java:106)

at com.esotericsoftware.kryo.serializers.FieldSerializer.read(FieldSerializer.java:528)

at com.esotericsoftware.kryo.Kryo.readClassAndObject(Kryo.java:786)

at SerializationTest.readObj(SerializationTest.java:39)

at SerializationTest.main(SerializationTest.java:27)

我曾希望可以对PrintWriter对象outObj进行序列化和反序列化,并且该对象的状态将保持不变,因此我仍然可以使用反序列化的对象来写“ Hello”,该对象将被保存在缓冲区中.

有谁知道这是怎么回事以及如何纠正此错误？