Hamcrest matcher that checks if the string is as expected, ignoring line order.

StringIsEqualIgnoringLineOrder.java

import java.util.Arrays;

import org.hamcrest.Description;
import org.hamcrest.Matcher;
import org.hamcrest.TypeSafeMatcher;

public class StringIsEqualIgnoringLineOrder extends TypeSafeMatcher<String> {
    private final String expected;
    private final String[] expectedLines;

    private StringIsEqualIgnoringLineOrder(String expected) {
        this.expected = expected;
        expectedLines = expected.split("\r?\n");
        Arrays.sort(expectedLines);
    }

    @Override
    public void describeTo(Description description) {
        description.appendText("a string (ignoring line order) ").appendValue(expected);
    }

    @Override
    protected boolean matchesSafely(String actual) {
        String[] actualLines = actual.split("\r?\n");
        Arrays.sort(actualLines);
        return Arrays.equals(expectedLines, actualLines);
    }

    /** Creates a matcher that checks if the string is as expected, ignoring line order. */
    public static Matcher<String> equalToIgnoringLineOrder(String expected) {
        return new StringIsEqualIgnoringLineOrder(expected);
    }
}