NullPointerException when adding an object into a Vector Class

Question

So here is the code:
package Image;
import java.io.Serializable;
import java.util.Vector;
public class Album implements Serializable{
private String name;
private String password;
Vector<ImageClass> allImages;
public Album( String name, String password, Vector<ImageClass> allImages) {
this.name = name;
this.password = password;
this.allImages = allImages;
public Album() {
public Vector<ImageClass> getAllImages() {
return allImages;
public void setAllImages(Vector<ImageClass> allImages) {
this.allImages = allImages;
public String getName() {
return name;
public void setName(String name) {
this.name = name;
public String getPassword() {
return password;
public void setPassword(String password) {
this.password = password;
public void addIC(ImageClass ic){
allImages.add(ic);
public ImageClass getIC(int pos){
ImageClass ic = allImages.get(pos);
return ic;
Now I got an NullPointerException when I call the getIC Method from another class of another package
Here is the part of code of that class.
private void SaveMenuItemActionPerformed(java.awt.event.ActionEvent evt) {                                            
ImageClass ic = new ImageClass();
ic.setTitle(ImageTextField.getText());
ic.setDescription(DescriptionTextArea.getText());
try {
ic.setReferenceNumber(Integer.parseInt(ReferenceTextField.getText()));
} catch (NumberFormatException nfe) {
JOptionPane.showMessageDialog(null, "Reference Number is not in a correct format");
try {
ic.setDate(new SimpleDateFormat("dd/MM/yyyy").parse(DateTextField.getText(), new ParsePosition(0)));
} catch (IllegalArgumentException iae) {
JOptionPane.showMessageDialog(null, "Date is not in correct format");
ic.setImageData(imageData);
if(a==null){
JOptionPane.showMessageDialog(this,"Please, create or open an Album");
}else{
a.addIC(ic);
try{
ObjectOutputStream oos;
FileOutputStream fos = new FileOutputStream(album, true);
oos = new ObjectOutputStream(fos);
oos.writeObject(a);
oos.flush();
oos.close();
}catch(FileNotFoundException fnfe){
fnfe.printStackTrace();
}catch(IOException ioe){
ioe.printStackTrace();
}

Answer 1

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