This can easily be done using StringUtils present in Apache commons. Here is the complete example on the usage.
public static int indexOfIgnoreCase(String str,
String searchStr,
int startPos)
Case in-sensitive find of the first index within a String from the specified position.
A null String will return -1. A negative start position is treated as zero. An empty ("") search String always matches. A start position greater than the string length only matches an empty search String.
StringUtils.indexOfIgnoreCase(null, *, *) = -1
StringUtils.indexOfIgnoreCase(*, null, *) = -1
StringUtils.indexOfIgnoreCase("", "", 0) = 0
StringUtils.indexOfIgnoreCase("aabaabaa", "A", 0) = 0
StringUtils.indexOfIgnoreCase("aabaabaa", "B", 0) = 2
StringUtils.indexOfIgnoreCase("aabaabaa", "AB", 0) = 1
StringUtils.indexOfIgnoreCase("aabaabaa", "B", 3) = 5
StringUtils.indexOfIgnoreCase("aabaabaa", "B", 9) = -1
StringUtils.indexOfIgnoreCase("aabaabaa", "B", -1) = 2
StringUtils.indexOfIgnoreCase("aabaabaa", "", 2) = 2
StringUtils.indexOfIgnoreCase("abc", "", 9) = 3
Parameters:
- str - the String to check, may be null
- searchStr - the String to find, may be null
- startPos - the start position, negative treated as zero
Returns: The first index of the search String, -1 if no match or null string input