Cast Object array to Custom Class array

Question

i created a class derived of Object and I have a object array.
how to do cast object array to my class array?

public class CastArray{

public CastArray(){
}

public long toLong(){
    return Long.parseLong(this.toString());
}    

public double toDouble(){
    return Double.parseDouble(this.toString());
}

public int toInteger(){
    return Integer.parseInt(this.toString());
}
}<br />

return Error:
java.lang.ClassCastException: [Ljava.lang.Object; cannot be cast to [LBasic.CastArray;

In java you don't need to explicitly write "extends Object". — Scorpion
– Scorpion, Commented Nov 5, 2011 at 6:42

aishwarya · Accepted Answer · 2011-11-05 06:45:49Z

3

The question is a bit vague but let me make an attempt to answer it. if the object array is actually an array of your class, you can do a direct cast to your array e.g. A[] a = (A[]) objArray;. Alternatively, if you know that each element can be cast into your class (is an instance of your class or one of its sub classes), you can clone it by creating a new array and adding each element with a cast to your class. e.g.:

A[] a = new A[objArray.length];
int i = 0;
for (Object o : objArray) {
   a[i++] = (A) o;
}

answered Nov 5, 2011 at 6:45

aishwarya

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1 Comment

bestsss Over a year ago

this is how it's done System.arrayCopy(objArray, 0, a, 0, a.length)

Tom · Accepted Answer · 2011-11-05 06:46:27Z

1

It sounds like you're asking how to do this:

Object[] objectArray = {};

CastArray castArray = (CastArray)objectArray;

If this is the case you can't.

answered Nov 5, 2011 at 6:46

Tom

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1 Comment

slott Over a year ago

Well one could do something like this: Badge[] badges = (Badge[]) clazz.cast(Array.newInstance(clazz.getComponentType(), 0));

Omnaest · Accepted Answer · 2011-11-05 08:51:54Z

1

The Arrays.copyOf(...) could be a solution for you.

Best regards!

answered Nov 5, 2011 at 8:51

Omnaest

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