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How do I access a config file inside the jar?

I’m using FlatPack to parse and load data from flat files. This requires loading a config file that stores mappings of the columns of the flat file.

I have a constant to define the location of the mapping file:

private static final String MAPPING_FILE = "src/com/company/config/Maping.pzmap.xml";

I have a parse(File dataFile) method that actually does the parsing:

private void parse(File dataFile) throws FileNotFoundException, SQLException {
        Parser parser;"Parsing " + dataFile.getName());

        FileReader mappingFileReader = new FileReader(MAPPING_FILE);
        FileReader dataFileReader = new FileReader(dataFile);

        parser = DefaultParserFactory.getInstance().newFixedLengthParser(mappingFileReader, dataFileReader);

        DataSet dataSet = parser.parse();

        //process the data

When I jar up everything and run it as a jar – it bombs out on FileReader mappingFileReader = new FileReader(MAPPING_FILE); with a FileNotFoundException. That file is inside the jar though.

How do I get to it?

I’ve looked at this question and this question about accessing files inside jars and they both recommend temporarily extracting the file. I don’t want to do that though.



if it’s inside a JAR, it’s not a File, generally speaking. You should load the data using Class.getResourceAsStream(String), or something similar.