[java] Test if a string contains any of the strings from an array

How do I test a string to see if it contains any of the strings from an array?

Instead of using

if (string.contains(item1) || string.contains(item2) || string.contains(item3))

You can use String#matches method like this:

System.out.printf("Matches - [%s]%n", string.matches("^.*?(item1|item2|item3).*$"));

The below should work for you assuming Strings is the array that you are searching within:

Arrays.binarySearch(Strings,"mykeytosearch",mysearchComparator);

where mykeytosearch is the string that you want to test for existence within the array. mysearchComparator - is a comparator that would be used to compare strings.

Refer to Arrays.binarySearch for more information.

We can also do like this:

if (string.matches("^.*?((?i)item1|item2|item3).*$"))

(?i): used for case insensitive
.*? & .*$: used for checking whether it is present anywhere in between the string.

Try this:

if (Arrays.asList(item1, item2, item3).stream().anyMatch(string::contains))

If you use Java 8 or above, you can rely on the Stream API to do such thing:

public static boolean containsItemFromArray(String inputString, String[] items) {
    // Convert the array of String items as a Stream
    // For each element of the Stream call inputString.contains(element)
    // If you have any match returns true, false otherwise
    return Arrays.stream(items).anyMatch(inputString::contains);
}

Assuming that you have a big array of big String to test you could also launch the search in parallel by calling parallel(), the code would then be:

return Arrays.stream(items).parallel().anyMatch(inputString::contains); 

And if you are looking for case insensitive match, use pattern

Pattern pattern = Pattern.compile("\\bitem1 |item2\\b",java.util.regex.Pattern.CASE_INSENSITIVE);

Matcher matcher = pattern.matcher(input);
if (matcher.find()) { 
    ...
}

The easiest way would probably be to convert the array into a java.util.ArrayList. Once it is in an arraylist, you can easily leverage the contains method.

public static boolean bagOfWords(String str)
{
    String[] words = {"word1", "word2", "word3", "word4", "word5"};  
    return (Arrays.asList(words).contains(str));
}

if (Arrays.asList(array).contains(string))

Since version 3.4 Apache Common Lang 3 implement the containsAny method.

Here is one solution :

public static boolean containsAny(String str, String[] words)
{
   boolean bResult=false; // will be set, if any of the words are found
   //String[] words = {"word1", "word2", "word3", "word4", "word5"};

   List<String> list = Arrays.asList(words);
   for (String word: list ) {
       boolean bFound = str.contains(word);
       if (bFound) {bResult=bFound; break;}
   }
   return bResult;
}

If you are seraching for whole words you can do this that works case insensitive.

private boolean containsKeyword(String line, String[] keywords)
{
    String[] inputWords = line.split(" ");

    for (String inputWord : inputWords)
    {
        for (String keyword : keywords)
        {
            if (inputWord.equalsIgnoreCase(keyword))
            {
                return true;
            }
        }
    }

    return false;
}

import org.apache.commons.lang.StringUtils;

String Utils

Use:

StringUtils.indexOfAny(inputString, new String[]{item1, item2, item3})

It will return the index of the string found or -1 if none is found.

A more groovyesque approach would be to use inject in combination with metaClass:

I would to love to say:

String myInput="This string is FORBIDDEN"
myInput.containsAny(["FORBIDDEN","NOT_ALLOWED"]) //=>true

And the method would be:

myInput.metaClass.containsAny={List<String> notAllowedTerms->
   notAllowedTerms?.inject(false,{found,term->found || delegate.contains(term)})
}

If you need containsAny to be present for any future String variable then add the method to the class instead of the object:

String.metaClass.containsAny={notAllowedTerms->
   notAllowedTerms?.inject(false,{found,term->found || delegate.contains(term)})
}