Reset ObjectOutPutStream to update new object state?
I want to reset ObjectOutPutStream to update the new object state. But why it doesn't effect. The below code outputs "BEFORE" instead of "AFTER"? What's wrong with my code?
package test;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.io.Serializable;
public class Serialization {
public static void main(String[] strs) {
String filename = "E:\\myObject.data";
FileOutputStream fos = null;
ObjectOutputStream out = null;
MyObject myObject = new MyObject();
try {
myObject.setValue("BEFORE");
fos = new FileOutputStream(filename);
out = new ObjectOutputStream(fos);
out.writeObject(myObject);
out.reset();
myObject.setValue("AFTER");
out.writeObject(myObject);
out.close();
} catch (IOException ex) {
ex.printStackTrace();
}
try {
FileInputStream fis = null;
ObjectInputStream in = null;
fis = new FileInputStream(filename);
in = new ObjectInputStream(fis);
myObject = (MyObject) in.readObject();
System.out.println(myObject.getValue());
in.close();
} catch (IOException ex) 开发者_运维问答{
ex.printStackTrace();
} catch (ClassNotFoundException ex) {
ex.printStackTrace();
}
}
public static class MyObject implements Serializable {
private static final long serialVersionUID = 5222199410120362372L;
private String value;
public void setValue(String value) {
this.value = value;
}
public String getValue() {
return value;
}
}
}
You are writing two copies of an object but only reading one. If you read two objects you will see BEFORE and AFTER.
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