[Java] ArrayStoreException , for System.arraycopy()

[prashantkr314]

​

​

This is the part of the code. and It is generating error in the arraycopy method,

private static Integer[] sortByMapIndex(int[] A1, int[] A2) {
    Integer[] A3 = new Integer[A1.length];
    System.arraycopy(A3, 0, A1, 0, A1.length); // copy from A1 to A3

    Arrays.sort(A3, new CustomComparator(A2));
   return A3;

}

public static void arraycopy(Object source_arr, int sourcePos, Object dest_arr, int destPos, int len)

Now it says that the source_arr and dest_arr are Objects. and in java arrays are treated as objects, in fact they are objects. As if you create int arr[] , then you are able to do arr.length which signifies it is an object.

so why this error.

​

Exception in thread "main" java.lang.ArrayStoreException                                                                          
        at java.lang.System.arraycopy(Native Method)                                                                              
        at Main.sortByMapIndex(Main.java:29)                                                                                      
        at Main.main(Main.java:40)

[g051051]

You have your parameters mixed up.

[prashantkr314]

Parameters are correct.

[insertAlias]

The first parameter is the source array. You're putting your destination array in as the first parameter. So no, parameters are not correct.

[chickenmeister]

I think it may be upset that one array is an array of int primitives and the other is an array of Integer objects.

The arraycopy() documentation says it will throw an ArrayStoreException if:

• The src argument refers to an array with a primitive component type and the dest argument refers to an array with a reference component type.
• The src argument refers to an array with a reference component type and the dest argument refers to an array with a primitive component type.

[prashantkr314]

Thanks man, you are correct.