关于java：它是什么意思：serializable类没有声明一个静态的最终serialVersionUID字段？

What does it mean: The serializable class does not declare a static final serialVersionUID field?

本问题已经有最佳答案，请猛点这里访问。

标题中有警告信息。我想理解并删除它。我已经找到了一些关于这个问题的答案，但是我不理解这些答案，因为技术术语太多了。能用简单的词来解释这个问题吗？

另外，我知道OOP是什么。我知道什么是对象、类、方法、字段和实例化。

P.P.S.如果有人需要我的代码，请点击这里：

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import java.awt.*;
import javax.swing.*;

public class HelloWorldSwing extends JFrame {

JTextArea m_resultArea = new JTextArea(6, 30);

//====================================================== constructor
public HelloWorldSwing() {
//... Set initial text, scrolling, and border.
m_resultArea.setText("Enter more text to see scrollbars");
JScrollPane scrollingArea = new JScrollPane(m_resultArea);
scrollingArea.setBorder(BorderFactory.createEmptyBorder(10,5,10,5));

// Get the content pane, set layout, add to center
Container content = this.getContentPane();
content.setLayout(new BorderLayout());
content.add(scrollingArea, BorderLayout.CENTER);
this.pack();
}

public static void createAndViewJFrame() {
JFrame win = new HelloWorldSwing();
win.setTitle("TextAreaDemo");
win.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
win.setVisible(true);
}

//============================================================= main
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable(){
public void run(){
createAndViewJFrame();
}
});
}

}

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javadoc：from theP＞＜／

The serialization runtime associates with each serializable class a version number, called a serialVersionUID, which is used during deserialization to verify that the sender and receiver of a serialized object have loaded classes for that object that are compatible with respect to serialization. If the receiver has loaded a class for the object that has a different serialVersionUID than that of the corresponding sender's class, then deserialization will result in an InvalidClassException. A serializable class can declare its own serialVersionUID explicitly by declaring a field named "serialVersionUID" that must be static, final, and of type long:

你可以你的IDE to configure：P＞＜／

ignore instead of this，给警告。
安自动生成ID

对你的问题"(Additional as that the warning message它discussed is a reason GUI应用冻为什么我？"：P＞＜／

恩，不，我不能。它可以造成问题如果你是唯一的序列化和反序列化的对象，在不同的地方在他们(或时间)在(when)has changed the class will not result，恩在和冷冻，但在InvalidClassException。P＞＜／

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原因是documented here for the warning and the fixes无知，或是把off the warning put the following the宣言，在你的代码版本的UID到电源。the actual value is not start with；999，如果你喜欢它，但当你让不兼容的变化changes to the class is。P＞＜／

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public class HelloWorldSwing extends JFrame {

JTextArea m_resultArea = new JTextArea(6, 30);
private static final long serialVersionUID = 1L;

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the other of answers我有很多技术的信息。我会尽量回答，as requested，简单的条款。P＞＜／

序列化是你把安安审对象(如果你想它在RAW转储缓冲硬盘，保存它，它在运输流(例如，在二进制对象发送过安在插座，或其他网络)创建的对象序列化binary representation of an。(for黑莓Java序列化序列化的信息在线在线看维基百科)。P＞＜／

如果你不打算要序列化的类杂志，You can add the above你只是@SuppressWarnings("serial")舱位置。P＞＜／

如果你是，那么你会有一个序列化，of things to host the proper担心在中心周围使用的UUID。基本上，"is the UUID的方式对象的序列化版本"我知道，你也知道，任何process is that是反序列化反序列化properly。我看的版本控制的对象序列化的保证proper for for黑莓信息。P＞＜／

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it must be changed whenever anything
changes that affects the serialization
(additional fields, removed fields,
change of field order, ...)

这是不正确的，你unable will be for that to an authoriitative claim开源标准。当你让它should be changed a change that is the rules given in the在不兼容的版本序列化的对象和对象序列化规范section of the which does not专门开发，包括额外的域或change of场秩序，当你还没有提供readObject(), writeObject(),和/或readResolve()或/writeReplace()ETF方法和/或serializableFields宣言，可以应付with the change。P＞＜／

that can be any序列化的类(即Serializableimplements)should that must be宣布UID和当事affects changes that changed the序列化(额外的字段，字段的顺序的相变场removed，of，…)。checked value is the场在反序列化和序列化对象if the value of the does not equal the value of the class在VM is the current，安例外扔了。P＞＜／

这个值是已知的，特别是在与对象序列化它，即使它是静态的，for the原因上面描述的程序办理。P＞＜／

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