Download Java.io.ObjectOutputStream.writeFields() Method

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JAVA.IO.OBJECTOUTPUTSTREAM.WRITEFIELDS METHOD
http://www.tutorialspoint.com/java/io/objectoutputstream_writefields.htm
Copyright © tutorialspoint.com
Description
The java.io.ObjectOutputStream.writeFields method the buffered fields to the stream.
Declaration
Following is the declaration for java.io.ObjectOutputStream.writeFields method.
public void writeFields()
Parameters
NA
Return Value
This method does not return a value.
Exception
IOException -- if I/O errors occur while writing to the underlying stream
NotActiveException -- Called when a classes writeObject method was not called to write
the state of the object.
Example
The following example shows the usage of java.io.ObjectOutputStream.writeFields method.
package com.tutorialspoint;
import java.io.*;
public class ObjectOutputStreamDemo {
public static void main(String[] args) {
double d = 1.59875d;
try {
// create a new file with an ObjectOutputStream
FileOutputStream out = new FileOutputStream("test.txt");
ObjectOutputStream oout = new ObjectOutputStream(out);
// write something in the file
oout.writeObject(new Example());
oout.flush();
oout.close();
// create an ObjectInputStream for the file we created before
ObjectInputStream ois =
new ObjectInputStream(new FileInputStream("test.txt"));
// read an object from the stream and cast it to Example
Example a = (Example) ois.readObject();
// print var of a
System.out.println("" + a.var);
} catch (Exception ex) {
ex.printStackTrace();
}
}
static public class Example implements Serializable {
static int var = 76458;
// assign a new serialPersistentFields
private static final ObjectStreamField[] serialPersistentFields = {
new ObjectStreamField("var", Integer.TYPE)
};
private void readObject(ObjectInputStream in)
throws IOException, ClassNotFoundException {
// get the field and assign it at var
ObjectInputStream.GetField fields = in.readFields();
// get var
var = fields.get("var", 0);
}
private void writeObject(ObjectOutputStream out)
throws IOException {
// write into the ObjectStreamField array the variable string
ObjectOutputStream.PutField fields = out.putFields();
fields.put("var", var);
out.writeFields();
}
}
}
Let us compile and run the above program, this will produce the following result:
76458
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