The following should be matched:
AAA123
ABCDEFGH123
XXXX123
can I do: \".*123\" ?
There are lots of sophisticated regex testing and development tools, but if you just want a simple test harness in Java, here's one for you to play with:
String[] tests = {
"AAA123",
"ABCDEFGH123",
"XXXX123",
"XYZ123ABC",
"123123",
"X123",
"123",
};
for (String test : tests) {
System.out.println(test + " " +test.matches(".+123"));
}
Now you can easily add new testcases and try new patterns. Have fun exploring regex.