java – Eclipse character encoding

I am using Scanner to scan a .txt document in Java. However, when I open the .txt document in Eclipse, I notice some characters are not being recognized, and they are replaced with something that looks like this:

�

These characters won’t even let me scan the file as

    while(scan.hasNext)

automatically returns false (if these characters are not present, then I can scan the document just fine).

So, how do I get Eclipse to recognize these characters so I can scan? I can’t manually remove them because the document is quite large.
Thanks.