finding multiple occurences of a char in a string

So I am trying to make a check to see if there is more than one comma in an entry such as the following.

"Johnson, Mr. Derrik J."

I figured out that to make sure it has a comma can be...

if (stringHolder[1].indexOf(",") > 0 == false)

{

System.out.println ("");

System.out.println ("Error G");

}

So to make sure there are not more than 1 comma would be? I'm stuck.

[423 byte] By [jay2coola] at [2007-10-3 7:44:16]