The file isn't there. If it was it wouldn't throw the exception :-)
The likely culprit is the working directory differs from what is expected (that is, the current working directory does not contain a file with that name). This can be trivially verified with using the file's absolute path and observing that it is loaded correctly.
Alternatively, to find the current directory:
String cwd = new File(".").getAbsolutePath();
Happy coding.
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