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POSerializing objects with hashMap
 

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  1. POSerializing objects with hashMap
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    <p>This is my first time i try objects serializing. My problem is that when i call for saving new objects(Reminder.java objects) it saves them in the hash map but when i load it gives me the properties of the last saved object.</p> <p>So my question is:</p> <p>1.Saving - How do i "append" objects to a file ? </p> <p>2.Loading - how to iterate through them and get the right object (using the key class type MyDateClass) . Example will be welcomed. Thank you.</p> <pre><code>public void save(MyDateClass chosenDate, String string){ System.out.println("Trying to save"); reminderMap.put(chosenDate, string); //serializing an object : this.dateReminder = chosenDate; this.reminder = string; try { FileOutputStream fileOut = new FileOutputStream("/tmp/reminder.ser"); ObjectOutputStream out = new ObjectOutputStream(fileOut); out.writeObject(this); out.close(); fileOut.close(); System.out.printf("Serialized data is saved in /tmp/reminder.ser. "); }catch(IOException i) { i.printStackTrace(); } } public String Load(MyDateClass chosenDate){ System.out.println("Trying to load"); this.reminder = reminderMap.get(chosenDate); System.out.println(this.reminder); // deserialize Reminder e = null; try { FileInputStream fileIn = new FileInputStream("/tmp/reminder.ser"); ObjectInputStream in = new ObjectInputStream(fileIn); e = (Reminder) in.readObject(); in.close(); fileIn.close(); }catch(IOException i) { i.printStackTrace(); }catch(ClassNotFoundException c) { c.printStackTrace(); } return e.reminder; } } </code></pre>
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    1. USYevgeni
    1. USYevgeni
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    1. CO`new FileOutputStream("/tmp/reminder.ser");` opens the file in *create* mode. Look for another constructor which will allow you to open in *append* mode.
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      1. USMarko Topolnik
 

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