Writing objects to files

For a number of reasons, it might be desirable to write an object to a file for future usage. Perhaps your applet needs to keep some sort of "state" and between invocations, it needs to recall a "state" object. Maybe you have a number of different applets that all share data but need a way to do so indirectly without using RMI or CORBA.
 
A method to accomplish all of the above is to take an object and write it to a file for later retrieval and re-creation.
 
Here is some sample code that will write an object to a file:

 
import java.io.File;
import java.io.FileOutputStream;
import java.io.ObjectOutputStream;
import java.io.IOException;
 
public class WriteObjectToFile {
public void writeObject(String filename, Object obj) {
File objFile = new File(filename);
try {
FileOutputStream fos = new FileOutputStream(objFile);
ObjectOutputStream oos = new ObjectOutputStream(fos);
 
oos.writeObject(obj);
oos.close();
}
catch (IOException e) {
System.out.println();
}
}
 
public static void main (String args[]) {
WriteObjectToFile objectWriter = new WriteObjectToFile();
 
Object localObj = new Object();
String test = "test";
localObj = (object)test;
 
objectWriter.writeObject("appletFile.obj", localObj);
}
}

Using this, you can retrieve the String object back, which will contain the value of "test." Enjoy!
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