Why I cannot use expected in JUnit 4

Question

Im trying to test method responsible for retreiving data from file. I want to test if exception is thrown properly.

   package contentfile;

import java.io.IOException;
import java.nio.file.Files;
import java.nio.file.Paths;
import java.util.stream.Stream;

public class ContentFileRetrieverService implements ContentFileRetriever {

    @Override
    public String[] getContentFile(String pathName) {

        Stream<String> contentFileStream;
        try {
            contentFileStream = Files.lines(Paths.get(pathName));
        } catch (IOException e) {
            throw new IllegalArgumentException(e);
        }

        return contentFileStream.toArray(String[]::new);
    }
}

My tests:

package contentfile;

import org.junit.jupiter.api.Test;

import static org.junit.Assert.*;

class ContentFileRetrieverServiceTest {

    private ContentFileRetrieverService contentFileRetrieverService = new ContentFileRetrieverService();

    @Test
    void getContentFile() {
        String pathFile = "src\\test\\java\\resources\\TestText.txt";
        String[] testedContent = contentFileRetrieverService.getContentFile(pathFile);
        String[] expected = {"Line1 a", "Line2 b c", "Line 3"};
        assertArrayEquals(expected, testedContent);
    }

    @Test(expected =  IllegalArgumentException.class)
    void getContentFileWhenFileDoesNotExist() {
        String pathFile = "unknown";
        String[] testedContent = contentFileRetrieverService.getContentFile(pathFile);
    }
}

pom,xml

<dependency>

    <groupId>org.junit.jupiter</groupId>
    <artifactId>junit-jupiter-api</artifactId>
    <version>RELEASE</version>
    <scope>test</scope>
</dependency>
<dependency>
    <groupId>junit</groupId>
    <artifactId>junit</artifactId>
    <version>4.12</version>
    <scope>test</scope>
</dependency>

It wont compile as it cannot resolve method excepted what I am making wrong? PS: Could you tell me if I test this method properly with these two methods?

Answer 1

You're mixing JUnit 4 and JUnit 5.

The expected element exists in the JUnit4 @Test

JUnit 5 offers more powerful assertThrows instead