I get these weird characters when I try to print out a vector element!

Question

I\'m using Netbeans. When I run the program below, I get this as output [I@de6ced! How come?

import java.util.Arrays;
import java.util.Vector;

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Answer 1

[I@de6ced can be broken down as:
- [ an array
- I of integers
- de6ced with this reference hash-code (which, in Sun Java, is basically the reference)

toString() for Object returns somethine like ClassName@HashCode, which is exactly what you're seeing happen here just with the (rather wierd) primitive-array classes.

The problem is that the wrong type is being inferred by the List asList(T...) method. Change your code to use Integer[] instead of int[]. This is a consequence of int being primitive, but int[] is an object.

You can see this directly:

System.out.println(Arrays.asList(new int[]{5}));

=> [[I@some reference

System.out.println(Arrays.asList(new Integer[]{5}).get(0));

=> 5