100 MB characters in object

Question

We are using java 1.5 in our application on HP UX 11.
In one of the functionality we are saving java objects to hard disk and reading them later.
code is like --
file=new File(path);
fileOut = new FileOutputStream (file);
objOut = new ObjectOutputStream (fileOut);
objOut.writeObject(object);
objOut.close();
fileOut.close();
for reading we use readObject method.
In normal cases size of object files on disk is not more than 35 kb.
This works fine in normal scenarios but if end user enters some special characters from MS word or excel then size of files is increased to 100 MB dramatically.If we open the object file in some editor then we can see a series of latin characters like à à à à à à (millions of characters).
While taking input from application user we are accepting only 20 characters.
I am not able to understand how single character is converted to millions of characters?
This is killing JVM...

Answer 1

Thanks for reply.
I have created a sample class saveObject for example.This will write object in C drive in case of windows (<1kb).
import java.io.File;
import java.io.FileOutputStream;
import java.io.ObjectOutputStream;
public class saveObject {
    public saveObject() {
    public static void writeObject(Object object , String path) {
           File file=null;
           FileOutputStream fileOut=null;
           ObjectOutputStream objOut=null;
           try {
               file=new File(path);
               fileOut = new FileOutputStream (file);
               objOut = new ObjectOutputStream (fileOut);
               objOut.writeObject(object);
               objOut.close();
               fileOut.close();
           } catch (Exception e){
                e.printStackTrace();
           } finally {
               file=null;
               fileOut=null;
               objOut=null;
    public static void main(String[] args) {
        writeObject("WallStreet 2nd A LA","C://test.obj");
}We are facing issue only in HP UNIX . The code works fine in Windows and Linux environment.
More Details : We have web application in which we accept data from users in html forms and save this to disk on temporary basis.
Issue is faced with address field where user is doing copy paste from excel/word rather than typing in form.