How do I check if a string contains a list of characters?

Question

How do I check if a list of characters are in a String, for example \"ABCDEFGH\" how do I check if any one of those is in a string.

Answer 1

Use Apache Commons StringUtils.containsAny()..satisfies a lot of different use cases one might have for checking if certain characters exist in a string.

https://commons.apache.org/proper/commons-lang/apidocs/org/apache/commons/lang3/StringUtils.html#containsAny-java.lang.CharSequence-char...-

Answer 2

I think this is a newbie question, so i will give you the easies method i can think of: using indexof complex version include regex you can try if you want.

Answer 3

If "ABCDEFGH" is in a string variable, the regular expression solution is not good. It will not work if the string contains any character that has a special meaning in regular expressions. Instead I suggest:

    Set<Character> charsToTestFor = "ABCDEFGH".chars()
            .mapToObj(ch -> Character.valueOf((char) ch))
            .collect(Collectors.toSet());
    String stringToTest = "asdhAkldffl";
    boolean anyCharInString = stringToTest.chars()
            .anyMatch(ch -> charsToTestFor.contains(Character.valueOf((char) ch)));
    System.out.println("Does " + stringToTest + " contain any of " + charsToTestFor + "? " + anyCharInString);

With the strings asdhAkldffl and ABCDEFGH this snippet outputs:

Does asdhAkldffl contain any of [A, B, C, D, E, F, G, H]? true

Answer 4

From Guava: CharMatcher.matchesAnyOf

private static final CharMatcher CHARACTERS = CharMatcher.anyOf("ABCDEFGH");
assertTrue(CHARACTERS.matchesAnyOf("39823839A983923"));

Answer 5

The cleanest way to implement this is using StringUtils.containsAny(String, String)

package com.sandbox;

import org.apache.commons.lang.StringUtils;
import org.junit.Test;

import static org.junit.Assert.assertFalse;
import static org.junit.Assert.assertTrue;

public class SandboxTest {

    @Test
    public void testQuestionInput() {
        assertTrue(StringUtils.containsAny("39823839A983923", "ABCDEFGH"));
        assertTrue(StringUtils.containsAny("A", "ABCDEFGH"));
        assertTrue(StringUtils.containsAny("ABCDEFGH", "ABCDEFGH"));
        assertTrue(StringUtils.containsAny("AB", "ABCDEFGH"));
        assertFalse(StringUtils.containsAny("39823839983923", "ABCDEFGH"));
        assertFalse(StringUtils.containsAny("", "ABCDEFGH"));
    }

}

Maven dependency:

    <dependency>
        <groupId>org.apache.commons</groupId>
        <artifactId>commons-lang3</artifactId>
        <version>3.5</version>
    </dependency>

Answer 6

use regular expression in java to check using str.matches(regex_here) regex in java

for example:

    if("asdhAkldffl".matches(".*[ABCDEFGH].*"))
    {
        System.out.println("yes");
    }