adam bien's blog

How To Read A File from JUnit Test 📎

To read the file: src/test/resources/test.file in a unit/integration test, the method Path.of is useful to set the working directory:


import java.io.IOException;
import java.nio.file.Files;
import java.nio.file.Path;
import static org.hamcrest.CoreMatchers.is;
import static org.hamcrest.MatcherAssert.assertThat;
import org.junit.Before;
import org.junit.Test;    

public class ReadFileTest {

    private Path workingDir;

    @Before
    public void init() {
        this.workingDir = Path.of("", "src/test/resources");
    }

    @Test
    public void read() throws IOException {
        Path file = this.workingDir.resolve("test.file");
        String content = Files.readString(file);
        assertThat(content, is("duke"));
    }

}

The method Files.readString ships with Java 11+.

Path.of should be preferred over Paths.get. Thanks to @sormuras for the hint