What happened to POI

I had to read a XLSX file in POI today

Problem 1:
You can no longer use the old
HSSFWorkbook wb     = new HSSFWorkbook(fileInputStream); 
syntax
or you will get :

The supplied data appears to be in the Office 2007+ XML. You are calling the part of POI that deals with OLE2 Office Documents. You need to call a different part of POI to process this data (eg XSSF instead of HSSF)
org.apache.poi.poifs.filesystem.OfficeXmlFileException: The supplied data appears to be in the Office 2007+ XML. You are calling the part of POI that deals with OLE2 Office Documents. You need to call a different part of POI to process this data (eg XSSF instead of HSSF)

Problem 2:
So I tried to use the new API
Workbook workbook = WorkbookFactory.create(fileInputStream);

But where is org.apache.poi.ss.usermodel.WorkbookFactory ??

This is because you need another dependably now. Go figure.

        <dependency>
            <groupId>org.apache.poi</groupId>
            <artifactId>poi</artifactId>
            <version>3.8</version>
        </dependency>
        <dependency>
            <groupId>org.apache.poi</groupId>
            <artifactId>poi-ooxml</artifactId>
            <version>3.8</version>
        </dependency>


Problem 3:

So as a 'good' Java dev, I started with unit testing, but I did not want to read a file in my JUnit test.
I came across this : http://stackoverflow.com/questions/2597271/easy-to-get-a-test-file-into-junit

My JUnit now looks like :

public class TestCalculator {

    @Rule
    public ResourceFile res = new ResourceFile("/Comparative.xlsx");// this file is in my test resources

    @Before
    public void before() throws IOException{
        Assert.assertNotNull( res.getFile());
    }
    @Test
    public void testParseXLSDoc(){
        Calculator c = new Calculator(res.file.getAbsolutePath());//the Java File
        c.parseActiveDocument();  
    }
}

//from stackoverflow
public class ResourceFile extends ExternalResource {

    String res;
    File file = null;
    InputStream stream;

    public ResourceFile(String res) {
        this.res = res;
    }

    public File getFile() throws IOException {
        if (file == null) {
            createFile();
        }
        return file;
    }

    public InputStream getInputStream() {
        return stream;
    }

    public InputStream createInputStream() {
        return getClass().getResourceAsStream(res);
    }

    public String getContent() throws IOException {
        return getContent("utf-8");
    }

    public String getContent(String charSet) throws IOException {
        InputStreamReader reader = new InputStreamReader(createInputStream(),
                Charset.forName(charSet));
        char[] tmp = new char[4096];
        StringBuilder b = new StringBuilder();
        try {
            while (true) {
                int len = reader.read(tmp);
                if (len < 0) {
                    break;
                }
                b.append(tmp, 0, len);
            }
            reader.close();
        } finally {
            reader.close();
        }
        return b.toString();
    }

    @Override
    protected void before() throws Throwable {
        super.before();
        stream = getClass().getResourceAsStream(res);
    }

    @Override
    protected void after() {
        try {
            if (stream != null) {
                stream.close();
            }
        } catch (IOException e) {
            // ignore
        }
        if (file != null) {
            file.delete();
        }
        super.after();
    }

    private void createFile() throws IOException {
        file = new File(".", res);
        InputStream stream = getClass().getResourceAsStream(res);
        try {
            file.createNewFile();
            FileOutputStream ostream = null;
            try {
                ostream = new FileOutputStream(file);
                byte[] buffer = new byte[4096];
                while (true) {
                    int len = stream.read(buffer);
                    if (len < 0) {
                        break;
                    }
                    ostream.write(buffer, 0, len);
                }
            } finally {
                if (ostream != null) {
                    ostream.close();
                }
            }
        } finally {
            stream.close();
        }
    }
}