java-tutorials/java-strings-ops/src/test/java/com/baeldung/string/SplitUnitTest.java

package com.baeldung.string;

import static org.assertj.core.api.Assertions.assertThat;

import java.util.Arrays;
import java.util.List;

import org.apache.commons.lang3.StringUtils;
import org.junit.jupiter.api.Test;

import com.google.common.base.Splitter;

public class SplitUnitTest {

    @Test
    public void givenString_whenSplit_thenReturnsArray_through_JavaLangString() {
        assertThat("peter,james,thomas".split(",")).containsExactly("peter", "james", "thomas");

        assertThat("car jeep scooter".split(" ")).containsExactly("car", "jeep", "scooter");

        assertThat("1-120-232323".split("-")).containsExactly("1", "120", "232323");

        assertThat("192.168.1.178".split("\\.")).containsExactly("192", "168", "1", "178");

        assertThat("b a, e, l.d u, n g".split("\\s+|,\\s*|\\.\\s*")).containsExactly("b", "a", "e", "l", "d", "u", "n", "g");
    }

    @Test
    public void givenString_whenSplit_thenReturnsArray_through_StringUtils() {
        StringUtils.split("car jeep scooter");

        assertThat(StringUtils.split("car jeep scooter")).containsExactly("car", "jeep", "scooter");

        assertThat(StringUtils.split("car    jeep   scooter")).containsExactly("car", "jeep", "scooter");

        assertThat(StringUtils.split("car:jeep:scooter", ":")).containsExactly("car", "jeep", "scooter");

        assertThat(StringUtils.split("car.jeep.scooter", ".")).containsExactly("car", "jeep", "scooter");
    }

    @Test
    public void givenString_whenSplit_thenReturnsList_Splitter() {
        // given
        List<String> resultList = Splitter.on(',')
            .trimResults()
            .omitEmptyStrings()
            .splitToList("car,jeep,,   scooter");

        assertThat(resultList).containsExactly("car", "jeep", "scooter");
    }

    @Test
    public void givenStringContainsSpaces_whenSplitAndTrim_thenReturnsArray_using_Regex() {
        assertThat(" car , jeep,  scooter ".trim()
            .split("\\s*,\\s*")).containsExactly("car", "jeep", "scooter");

    }

    @Test
    public void givenStringContainsSpaces_whenSplitAndTrim_thenReturnsArray_using_java_8() {
        assertThat(Arrays.stream(" car , jeep,  scooter ".split(","))
            .map(String::trim)
            .toArray(String[]::new)).containsExactly("car", "jeep", "scooter");
    }
}