在没有serialVersionUID的情况下反序列化对象时出现问题 [英] issue while deserializing the object with no serialVersionUID

问题描述

 首先 我   获取   例外   -   ` 
 
  java 。 io 。 InvalidClassException   local   class  不兼容：  stream   classdesc   serialVersionUID   =   4597316331807173261 ， local   class   serialVersionUID   =  -3344057582987646196`，
 
  as         `serialVersionUID`      class   COOKIE       API   HtmlUnit    我  am  使用，此  exception  发生  as    类  Cookie  是 已更改 因为 我们  upgrade     version   `HtmlUnit`， so   what   idea     to   my   mind     to   avoid    匹配  `serialversionUID` 而  deserialing ， so  我 有 尝试     < span class =code-leadattribute>解决方案  ::  
 
  I    覆盖  readClassDescriptor    ObjectInputStre的class =code-leadattribute> am   class     this  方式 
 
 < pre  lang =java> protected  ObjectStreamClass  readClassDescriptor（） throws   IOException ， ClassNotFoundException  {
  ObjectStreamClass   resultClassDescriptor  =  super  。 readClassDescriptor（）;  //  最初流描述符 
 类  localClass   =   Class  .forName（ resultClassDescriptor.getName（））;  //  此描述符所代表的本地JVM中的类。 
  if  （localClass  == null）{
  System  。  out  .println（No  local   class   for    +   resultClassDescriptor  .getName（））; 
  return  resultClassDescriptor; 
 }  
  ObjectStreamClass   localClassDescriptor   =   ObjectStreamClass  .lookup（localClass）; 
 如果 （localClassDescriptor ！= null）{ //  仅当类实现可序列化 
  final   long   localSUID  =  localClassDescriptor    getSerialVersionUID（）; 
  final   long   streamSUID  < span class =code-leadattribute> =   resultClassDescriptor  .getSerialVersionUID（）; 
 如果 （streamSUID ！= localSUID）{ //  检查serialVersionUID不匹配。 
  final   StringBuffer   s  =  new  StringBuffer（Overriding  serialized   class   version   mismatch  ： ）;  
  s  。 append（local  serialVersionUID   = ）。append（localSUID）; 
  s  .append（ stream   serialVersionUID   = ）。append（streamSUID）; 
 异常  e   =  < span class =code-leadattribute> new  InvalidClassException（s.toString（））; 
 系统。 out  .println（潜在致命 反序列化 操作。  +  e）; 
  resultClassDescriptor   =  localClassDescriptor;  //  使用本地类描述符进行反序列化 
  }  
 }  
  return  resultClassDescriptor; 
 }  

现在它将我的streamUID转换为LocalUID，但这个例外来找我



`StreamCorruptedException：无效的类型代码：00`

解决方案

Firstly I was getting the Exception - `

    java.io.InvalidClassException local class incompatible: stream classdesc serialVersionUID = 4597316331807173261, local class serialVersionUID = -3344057582987646196`,

 as there is not a `serialVersionUID` in the class COOKIE of the API HtmlUnit that I am using, this exception occurs as the class Cookie is changed because we upgrade the version of `HtmlUnit` , so what idea comes to my mind is to avoid the matching of `serialversionUID` while deserialing, so I have tried the below solution ::

I have overrided readClassDescriptor of ObjectInputStream class in this way 

<pre lang="java">protected ObjectStreamClass readClassDescriptor() throws IOException, ClassNotFoundException {
        ObjectStreamClass resultClassDescriptor = super.readClassDescriptor(); // initially streams descriptor
        Class localClass = Class.forName(resultClassDescriptor.getName()); // the class in the local JVM that this descriptor represents.
        if (localClass == null) {
            System.out.println("No local class for " + resultClassDescriptor.getName());
            return resultClassDescriptor;
        }
        ObjectStreamClass localClassDescriptor = ObjectStreamClass.lookup(localClass);
        if (localClassDescriptor != null) { // only if class implements serializable
            final long localSUID = localClassDescriptor.getSerialVersionUID();
            final long streamSUID = resultClassDescriptor.getSerialVersionUID();
            if (streamSUID != localSUID) { // check for serialVersionUID mismatch.
                final StringBuffer s = new StringBuffer("Overriding serialized class version mismatch: ");
                s.append("local serialVersionUID = ").append(localSUID);
                s.append(" stream serialVersionUID = ").append(streamSUID);
                Exception e = new InvalidClassException(s.toString());
                System.out.println("Potentially Fatal Deserialization Operation. " + e);
                resultClassDescriptor = localClassDescriptor; // Use local class descriptor for deserialization
            }
        }
        return resultClassDescriptor;
    }

and Now it converts my streamUID to LocalUID but this exception comes to me

`StreamCorruptedException: invalid type code: 00`

解决方案

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