Java Relative Path Issue

Question

I am facing an issue while trying to resolve a file path using relative paths in Java. I am not sure where I am failing at. Could you please help me out? Thanks!

@Test
public void testObjectNotNull() throws Exception{
    FileReader fileReader = new FileReader(getClass().getResource("./JavaPractice/resources/tests/codeeval/fileReaderTest.txt").toString());
    assertNotNull(fileReader);
}

Exception:

java.lang.NullPointerException
    at components.com.codeeval.FileReader.FileReaderTest.testObjectNotNull(FileReaderTest.java:13)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)

Directory Structure:

JavaPractice

--resources.tests.codeeval.fileReaderTest.txt (File that I am trying to access)

--tests.components.com.codeeval.FileReader.FileReaderTest.java (junit which is trying to access the above file)

Answer 1

Resources are not files. They are typically JAR file entries. You should use the resource API of Class or ClassLoader. That can return you an InputStream.

Answer 2

Your issue is because this

getClass().getResource("./JavaPractice/resources/tests/codeeval/fileReaderTest.txt")

is null. You are reading from the classpath and not a relative path per-se SO Change your code to
getClass().getResource("tests/codeeval/fileReaderTest.txt") and ensure that the resources folder is on your classpath. Also read up on loading from classpath

Answer 3

try this

InputStream in = Your_Class.class.getClassLoader().getResourceAsStream("resources/tests/codeeval/abc.txt");

 assertNotNull(in);
 Reader fr = new InputStreamReader(in, "utf-8");