CODEWITHSUNDEEP
javastring
user1835935
user1835935

Reputation: 45

String functions in java

Can we use "contains" and "equalignorecase" functions of string at same time.

i had a data in which i need to search a string "NBN", if found i need to update a flag. But im seeing there are 

"nBN","nBn","NBn","nbN","NbN","Nbn"

also existing in the set of data . so i'm getting multiple combinations and comparisons.

Is there any way to overcome these many comparisons by using both functions at a time ?

Upvotes: 2

Views: 413

Answers (5)

Raghvendra Garg
Raghvendra Garg

Reputation: 515

If you just want to check the wether your data contains "NBN" then StringUtils.containsIgnoreCase() is the best option as it serves the exact purpose. But if you also want to count the occurrences or anything else then writing a custom solution will be a better option.

Upvotes: 0

Ron
Ron

Reputation: 1508

From Apache Commons
http://commons.apache.org/proper/commons-lang/apidocs/src-html/org/apache/commons/lang3/StringUtils.html:

1337    public static boolean containsIgnoreCase(final CharSequence str, final CharSequence searchStr) {
1338        if (str == null || searchStr == null) {
1339            return false;
1340        }
1341        final int len = searchStr.length();
1342        final int max = str.length() - len;
1343        for (int i = 0; i <= max; i++) {
1344            if (CharSequenceUtils.regionMatches(str, true, i, searchStr, 0, len)) {
1345                return true;
1346            }
1347        }
1348        return false;
1349    }

http://commons.apache.org/proper/commons-lang/javadocs/api-3.0/src-html/org/apache/commons/lang3/CharSequenceUtils.html 

187        static boolean regionMatches(CharSequence cs, boolean ignoreCase, int thisStart,
188                CharSequence substring, int start, int length)    {
189            if (cs instanceof String && substring instanceof String) {
190                return ((String) cs).regionMatches(ignoreCase, thisStart, ((String) substring), start, length);
191            } else {
192                // TODO: Implement rather than convert to String
193                return cs.toString().regionMatches(ignoreCase, thisStart, substring.toString(), start, length);
194            }
195        }

Upvotes: 0

Ron
Ron

Reputation: 1508

While there is no built in functionality for this directly, best practice is to convert both Strings to lower case then use contains()

String matchString = "NPN";
String lowercaseMatchString = matchString.toLowerCase();
String lowercase = stringToTest.toLowerCase();

return lowercaseMatchString.contains(lowercase);

Upvotes: 2

MadProgrammer
MadProgrammer

Reputation: 347234

Think you might find it easier to use String#toLowerCase instead of String#equalsIgnoreCase

For example...

if ("I want my NBN".toLowerCase().contains("nbn")) {...}

Upvotes: 4

Suresh Atta
Suresh Atta

Reputation: 121998

You can use Apache StringUtils#containsIgnoreCase()

 StringUtils.containsIgnoreCase("WholeString", "NBn");

Upvotes: 5

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