Java 无法反序列化所有对象的ArrayList-仅反序列化第一个对象
有很多java序列化/反序列化问题,但我找不到问题的答案。我运行GUI,三个音乐对象在运行时存储在ArrayList中(预编码): 下面是Music.java类(尽管我认为应该假设这个类的编码正确):Java 无法反序列化所有对象的ArrayList-仅反序列化第一个对象,java,deserialization,Java,Deserialization,有很多java序列化/反序列化问题,但我找不到问题的答案。我运行GUI,三个音乐对象在运行时存储在ArrayList中(预编码): 下面是Music.java类(尽管我认为应该假设这个类的编码正确): 问题在于文件。最初,我尝试使用music.ser并创建了一个GUI,并尝试从GUI中添加两位艺术家,以及上面提供的三位艺术家 我试着对它们进行序列化和反序列化,结果很顺利。后来我尝试从GUI中添加另一个元素,而在序列化和反序列化时,我发现它没有正确序列化 后来,我将文件名改为test.ser,当我
问题在于文件。最初,我尝试使用music.ser并创建了一个GUI,并尝试从GUI中添加两位艺术家,以及上面提供的三位艺术家 我试着对它们进行序列化和反序列化,结果很顺利。后来我尝试从GUI中添加另一个元素,而在序列化和反序列化时,我发现它没有正确序列化 后来,我将文件名改为test.ser,当我尝试从GUI添加三个美工师和从运行时添加三个美工师时,一切正常,当我尝试从GUI添加第四个美工师时,再次失败 您所需要做的就是删除该文件(如果存在),并在序列化和反序列化时创建一个新文件 样本代码随附
import java.awt.BorderLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.util.ArrayList;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JMenu;
import javax.swing.JMenuBar;
import javax.swing.JMenuItem;
import javax.swing.JPanel;
import javax.swing.JTextField;
public class TestGUI {
public static void main(String args[]) {
final ArrayList<Music> musicList = new ArrayList<Music>();
//Creating the Frame
JFrame frame = new JFrame("Chat Frame");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setSize(400, 400);
//Creating the MenuBar and adding components
JMenuBar mb = new JMenuBar();
JMenu m1 = new JMenu("FILE");
JMenu m2 = new JMenu("Help");
mb.add(m1);
mb.add(m2);
JMenuItem m11 = new JMenuItem("Open");
JMenuItem m22 = new JMenuItem("Save as");
m1.add(m11);
m1.add(m22);
//Creating the panel at bottom and adding components
JPanel panel = new JPanel(); // the panel is not visible in output
JLabel label = new JLabel("Enter Artist");
final JTextField tf = new JTextField(10); // accepts upto 10 characters
JLabel album = new JLabel("Enter Album");
final JTextField tf1 = new JTextField(10);
JButton send = new JButton("Send");
JButton reset = new JButton("Serialize");
panel.add(label); // Components Added using Flow Layout
panel.add(label); // Components Added using Flow Layout
panel.add(tf);
panel.add(album); // Components Added using Flow Layout
panel.add(tf1);
panel.add(send);
panel.add(reset);
send.addActionListener(new ActionListener() {
@Override
public void actionPerformed(ActionEvent arg0) {
Music m = new Music(tf.getText(), tf1.getText());
musicList.add(m);
tf1.setText("");
tf.setText("");
}
});
reset.addActionListener(new ActionListener() {
@Override
public void actionPerformed(ActionEvent arg0) {
try {
TestSerialization.serializeAndDeserialize(musicList);
} catch (Exception ex) {
}
}
});
//Adding Components to the frame.
frame.getContentPane().add(BorderLayout.CENTER, panel);
frame.getContentPane().add(BorderLayout.NORTH, mb);
frame.setVisible(true);
}
}
示例序列化类
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.util.ArrayList;
public class TestSerialization {
public static ArrayList<Music> serializeAndDeserialize(ArrayList<Music> musicList) throws Exception {
musicList.add(new Music("Metallica", "Master of Puppets"));
musicList.add(new Music("Pantera", "Far Beyond Driven"));
musicList.add(new Music("Kognitif", "Soul Food"));
// serialization method
try {
File f = new File("test.ser");
if (f.exists()) {
f.delete();
}
FileOutputStream fos = new FileOutputStream("test.ser", true);
ObjectOutputStream oos = new ObjectOutputStream(fos);
oos.writeObject(musicList);
oos.close();
fos.close();
for (Music m : musicList) {
System.out.println("AddMusic: " + m);
}
} catch (IOException ioe) {
ioe.printStackTrace();
}
// deserialization method
ArrayList<Music> musicList2 = new ArrayList<Music>();
try {
FileInputStream fis = new FileInputStream("test.ser");
ObjectInputStream ois = new ObjectInputStream(fis);
musicList2 = (ArrayList<Music>) ois.readObject();
ois.close();
fis.close();
for (Music m : musicList2) {
System.out.println("Reading Music: \n" + m.getArtist() + " - " + m.getAlbum());
}
}
catch (Exception ex) {
ex.printStackTrace();
}
return musicList2;
}
}
导入java.io.File;
导入java.io.FileInputStream;
导入java.io.FileOutputStream;
导入java.io.IOException;
导入java.io.ObjectInputStream;
导入java.io.ObjectOutputStream;
导入java.util.ArrayList;
公共类TestSerialization{
公共静态ArrayList serializeAndDeserialize(ArrayList musicList)引发异常{
musicList.add(新音乐(“金属舞曲”、“木偶大师”);
musicList.add(新音乐(“Pantera”、“远超驱动”);
音乐列表添加(新音乐(“Kognitif”,“灵魂食物”);
//序列化方法
试一试{
文件f=新文件(“test.ser”);
如果(f.exists()){
f、 删除();
}
FileOutputStream fos=新的FileOutputStream(“test.ser”,true);
ObjectOutputStream oos=新的ObjectOutputStream(fos);
oos.writeObject(musicList);
oos.close();
fos.close();
音乐(m:musicList){
System.out.println(“AddMusic:+m”);
}
}捕获(ioe异常ioe){
ioe.printStackTrace();
}
//反序列化方法
ArrayList MusicList 2=新的ArrayList();
试一试{
FileInputStream fis=新的FileInputStream(“test.ser”);
ObjectInputStream ois=新ObjectInputStream(fis);
musicList2=(ArrayList)ois.readObject();
ois.close();
fis.close();
音乐(m:MusicList 2){
System.out.println(“阅读音乐:\n”+m.getArtist()+“-”+m.getAlbum());
}
}
捕获(例外情况除外){
例如printStackTrace();
}
返回musicList2;
}
}
使用生成的版本UID,同时删除toString()方法并尝试一下,而不是使用默认的SerialAversionUID。这也不起作用。老实说,我不明白为什么会这样。@mahadevkalyansrikanth这些毫无意义的建议你的理由是什么?”GUI“怎么做?”?为什么Music
有JTextArea
字段?您是否希望它被序列化和反序列化,并神奇地出现在GUI中的某个地方?不会的。我怀疑它是否应该存在,但如果它应该存在,它肯定应该是volatile
@user207421:通过在JTextFields中输入艺术家和相册从GUI添加的。音乐课上的JTextArea错误地出现了-我在复制了一些代码后忘记删除它。我不希望它神奇地出现在GUI中。我只想反序列化.ser文件中的所有对象。那我就知道怎么处理了。他不需要exists()/delete()
code。在构造FileOutputStream
时,他只需要去掉append参数true
。您不能附加到对象流。@mahadev kalyan srikanth:谢谢。谢谢你。
public class Music implements Serializable {
/**
*
*/
private static final long serialVersionUID = 1L;
private String artist;
private String album;
JTextArea textArea;
public Music(String artist, String album) {
super();
this.artist = artist;
this.album = album;
}
public String getArtist() {
return artist;
}
public void setArtist(String artist) {
this.artist = artist;
}
public String getAlbum() {
return album;
}
public void setAlbum(String album) {
this.album = album;
}
@Override
public String toString() {
return artist + " - " + album + "\n";
}
}
import java.awt.BorderLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.util.ArrayList;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JMenu;
import javax.swing.JMenuBar;
import javax.swing.JMenuItem;
import javax.swing.JPanel;
import javax.swing.JTextField;
public class TestGUI {
public static void main(String args[]) {
final ArrayList<Music> musicList = new ArrayList<Music>();
//Creating the Frame
JFrame frame = new JFrame("Chat Frame");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setSize(400, 400);
//Creating the MenuBar and adding components
JMenuBar mb = new JMenuBar();
JMenu m1 = new JMenu("FILE");
JMenu m2 = new JMenu("Help");
mb.add(m1);
mb.add(m2);
JMenuItem m11 = new JMenuItem("Open");
JMenuItem m22 = new JMenuItem("Save as");
m1.add(m11);
m1.add(m22);
//Creating the panel at bottom and adding components
JPanel panel = new JPanel(); // the panel is not visible in output
JLabel label = new JLabel("Enter Artist");
final JTextField tf = new JTextField(10); // accepts upto 10 characters
JLabel album = new JLabel("Enter Album");
final JTextField tf1 = new JTextField(10);
JButton send = new JButton("Send");
JButton reset = new JButton("Serialize");
panel.add(label); // Components Added using Flow Layout
panel.add(label); // Components Added using Flow Layout
panel.add(tf);
panel.add(album); // Components Added using Flow Layout
panel.add(tf1);
panel.add(send);
panel.add(reset);
send.addActionListener(new ActionListener() {
@Override
public void actionPerformed(ActionEvent arg0) {
Music m = new Music(tf.getText(), tf1.getText());
musicList.add(m);
tf1.setText("");
tf.setText("");
}
});
reset.addActionListener(new ActionListener() {
@Override
public void actionPerformed(ActionEvent arg0) {
try {
TestSerialization.serializeAndDeserialize(musicList);
} catch (Exception ex) {
}
}
});
//Adding Components to the frame.
frame.getContentPane().add(BorderLayout.CENTER, panel);
frame.getContentPane().add(BorderLayout.NORTH, mb);
frame.setVisible(true);
}
}
import java.io.Serializable;
import javax.swing.JTextArea;
public class Music implements Serializable {
/**
*
*/
private static final long serialVersionUID = 1L;
private String artist;
private String album;
JTextArea textArea;
public Music(String artist, String album) {
super();
this.artist = artist;
this.album = album;
}
public String getArtist() {
return artist;
}
public void setArtist(String artist) {
this.artist = artist;
}
public String getAlbum() {
return album;
}
public void setAlbum(String album) {
this.album = album;
}
@Override
public String toString() {
return artist + " - " + album + "\n";
}
}
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.util.ArrayList;
public class TestSerialization {
public static ArrayList<Music> serializeAndDeserialize(ArrayList<Music> musicList) throws Exception {
musicList.add(new Music("Metallica", "Master of Puppets"));
musicList.add(new Music("Pantera", "Far Beyond Driven"));
musicList.add(new Music("Kognitif", "Soul Food"));
// serialization method
try {
File f = new File("test.ser");
if (f.exists()) {
f.delete();
}
FileOutputStream fos = new FileOutputStream("test.ser", true);
ObjectOutputStream oos = new ObjectOutputStream(fos);
oos.writeObject(musicList);
oos.close();
fos.close();
for (Music m : musicList) {
System.out.println("AddMusic: " + m);
}
} catch (IOException ioe) {
ioe.printStackTrace();
}
// deserialization method
ArrayList<Music> musicList2 = new ArrayList<Music>();
try {
FileInputStream fis = new FileInputStream("test.ser");
ObjectInputStream ois = new ObjectInputStream(fis);
musicList2 = (ArrayList<Music>) ois.readObject();
ois.close();
fis.close();
for (Music m : musicList2) {
System.out.println("Reading Music: \n" + m.getArtist() + " - " + m.getAlbum());
}
}
catch (Exception ex) {
ex.printStackTrace();
}
return musicList2;
}
}