HELP ...DONT UNDERSTAND Error

Code:

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//this is my hash table function
 public void hashTable(String s, int randX) {



        int key1 = (randX % 9);
        int c = (randX % 5) + 1;
        int i = 0;
        Integer check;

     
        check = (Integer) hashtable.get(key1);
              if (isEmpty(check)) {

            hashtable.put(key1, s);

        }
 else{
            System.out.println("is it empty?????" + isEmpty(check));
 }
    }

// this is my boolean check
    public static boolean isEmpty(Integer p) {
        boolean isnull = false;
        // System.out.println("ok here p is : " + p);
        //any variables you would need
        if (p == null) //{
        {
            System.out.println("it is true");
            isnull = true;
        }

        return isnull;

    }

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for some reason once the boolean fails it gives me this error





Exception in thread "AWT-EventQueue-0" java.lang.ClassCastException: java.lang.String cannot be cast to java.lang.Integer
at HashFunc.hashTable(HashFunc.java:237)
at HashFunc.actionPerformed(HashFunc.java:166)
at javax.swing.AbstractButton.fireActionPerformed(Abs tractButton.java:2028)
at javax.swing.AbstractButton$Handler.actionPerformed (AbstractButton.java:2351)
at javax.swing.DefaultButtonModel.fireActionPerformed (DefaultButtonModel.java:387)
at javax.swing.DefaultButtonModel.setPressed(DefaultB uttonModel.java:242)
at javax.swing.plaf.basic.BasicButtonListener.mouseRe leased(BasicButtonListener.java:236)
at java.awt.Component.processMouseEvent(Component.jav a:6352)
at javax.swing.JComponent.processMouseEvent(JComponen t.java:3267)
at java.awt.Component.processEvent(Component.java:611 7)
at java.awt.Container.processEvent(Container.java:208 5)
at java.awt.Component.dispatchEventImpl(Component.jav a:4714)
at java.awt.Container.dispatchEventImpl(Container.jav a:2143)
at java.awt.Component.dispatchEvent(Component.java:45 44)
at java.awt.LightweightDispatcher.retargetMouseEvent( Container.java:4621)
at java.awt.LightweightDispatcher.processMouseEvent(C ontainer.java:4282)
at java.awt.LightweightDispatcher.dispatchEvent(Conta iner.java:4212)
at java.awt.Container.dispatchEventImpl(Container.jav a:2129)
at java.awt.Window.dispatchEventImpl(Window.java:2478 )
at java.awt.Component.dispatchEvent(Component.java:45 44)
at java.awt.EventQueue.dispatchEvent(EventQueue.java: 635)
at java.awt.EventDispatchThread.pumpOneEventForFilter s(EventDispatchThread.java:296)
at java.awt.EventDispatchThread.pumpEventsForFilter(E ventDispatchThread.java:211)
at java.awt.EventDispatchThread.pumpEventsForHierarch y(EventDispatchThread.java:201)
at java.awt.EventDispatchThread.pumpEvents(EventDispa tchThread.java:196)
at java.awt.EventDispatchThread.pumpEvents(EventDispa tchThread.java:188)
at java.awt.EventDispatchThread.run(EventDispatchThre ad.java:122)

I can't see what your hashtable variable is or what put() is supposed to do, but I can tell that put() is trying to accept 2 integer variables and is receiving an integer and a string ( hashtable.put(key1, s); ).

ok put() is accepting two variables. an int(key) and a string(item). the problem is on my boolean check " isEmpty()

whenever i fails it never goes true it just spits the error out.

// i used the inbuilt hash table function.
Hashtable hashtable = new Hashtable(9);

hashtable.put(key1, s);// this put is part of the lib.

Quote:

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put() is trying to accept 2 integer variables and is receiving an integer and a string

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I think it's failing on

Code:

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check = (Integer) hashtable.get(key1);

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with

Code:

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ClassCastException: java.lang.String cannot be cast to java.lang.Integer

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Evidently that's a Hashtable<Integer, String> and the reference returned from get(...) can't be cast to an Integer.

db

Ok so how do i fix it?

Thank you

also to make that an object i have to type cast it as (Integer) if not its not gonna work..

if have any other ideas pls lemme know thank you

The solution depends upon wat does hashtable.get(key1) return ? does it return a valid value parsable to Integer ???? .
Why don't u use a Hashtable<Integer,Integer> instead.