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POJava writeObject is writing an empty ArrayList
 

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  1. POJava writeObject is writing an empty ArrayList
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    <p>I'm having trouble writing an <code>ArrayList</code> of a custom class to a file. I'm using</p> <pre><code>public static void SaveEmployees() throws FileNotFoundException, IOException{ ObjectOutputStream save = new ObjectOutputStream(new FileOutputStream("magicscheduleEmp.sav"); save.writeObject(employeeList); save.close(); } </code></pre> <p>Where <code>employeeList</code> is declared and initialized as an <code>ArrayList</code> of <code>Employees</code> (my class) in the main method. I have definitely added objects to <code>employeeList</code>, but calling <code>SaveEmployees</code> writes an empty <code>ArrayList</code> to the file. The <code>Employee</code> class is serializable.</p> <p>What am I doing wrong?</p> <p>Edit: employeeList is initialized here (in the main method)</p> <pre><code> public static ArrayList&lt;Employee&gt; employeeList = new ArrayList&lt;&gt;(); </code></pre> <p>and populated through user input (in another jFrame class)</p> <pre><code> if(MainUI.addempcheck == true){ Employee newEmployee = new Employee(LastName.getText(), FirstName.getText()); newEmployee.position = EmpType.getSelectedItem().toString(); MainUI.employeeList.add(newEmployee); MainUI.listModel.addElement(newEmployee.writeName().toString()); } try { MainUI.SaveEmployees(); } catch (FileNotFoundException ex) { Logger.getLogger(NewEmployeeUI.class.getName()).log(Level.SEVERE, null, ex); } catch (IOException ex) { Logger.getLogger(NewEmployeeUI.class.getName()).log(Level.SEVERE, null, ex); } this.dispose(); </code></pre> <p>I have a button which prints the contents of employeeList, and shows that the list is populated before I save it. Maybe it's a problem with calling SaveEmployees?</p>
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    1. PTQuestion
    1. USWilliam Regelmann
    1. USWilliam Regelmann
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      1. POJava writeObject is writing an empty ArrayList
      1. This table or related slice is empty.
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    1. COShow us how `employeeList` is initialized and populated. It must be a static field in your example.
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      1. POJava writeObject is writing an empty ArrayList
      1. USSotirios Delimanolis
    2. COWithout seeing what is going on with arraylist, I can only recommend you to write each element separately, like shown in this example: http://stackoverflow.com/a/6548204/1276128
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      1. POJava writeObject is writing an empty ArrayList
      1. USMarko Grešak
    3. COIf you're using an `ArrayList` to back your `List<Employee> employeeList` and you're sure your `Employee` class implements `Serializable`, then `employeeList` is empty.
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      1. POJava writeObject is writing an empty ArrayList
      1. USLuiggi Mendoza
 

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