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Properties File multi-line values using PropertiesConfiguration

So far, I have this project where I read in a properties file using PropertiesConfiguration (from Apache), edit the values I would like to edit, and then save change to the file. It keeps the comments and formatting and such, but one thing it does change is taking the multi-line values formatted like this:

key=value1,
    value2,
    value3

and turns it into the array style:

key=value1,value2,value3

I would like to be able to print those lines formatted as the were before.
I did this via this method:

PropertiesConfiguration config = new PropertiesConfiguration(configFile);
config.setProperty(key,value);
config.save();

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Answer

I created a work around in case anyone else needs this functionality. Also, there is probably a better way to do this, but this solution currently works for me.

First, set your PropertiesConfiguration delimiter to the new line character like so:

PropertiesConfiguration config = new PropertiesConfiguration(configFile);
config.setListDelimiter('n');

Then you will need to iterate through and update all properties (to set the format):

Iterator<String> keys = config.getKeys();
    while (keys.hasNext()) {
        String key = keys.next();

        config.setProperty(key,setPropertyFormatter(key, config.getProperty(key))) ;

    }

use this method to format your value list data (as shown above):

private List<String> setPropertyFormatter(String key, Object list) {
    List<String> tempProperties = new ArrayList<>();
    Iterator<?> propertyIterator = PropertyConverter.toIterator(list, 'n');;
    String indent = new String(new char[key.length() + 1]).replace('', ' ');

    Boolean firstIteration = true;
    while (propertyIterator.hasNext()) {
        String value = propertyIterator.next().toString();

        Boolean lastIteration = !propertyIterator.hasNext();

        if(firstIteration && lastIteration) {
            tempProperties.add(value);
            continue;
        }

        if(firstIteration) {
            tempProperties.add(value + ",\");
            firstIteration = false;
            continue;
        }

        if (lastIteration) { 
            tempProperties.add(indent + value);
            continue;
        } 

        tempProperties.add(indent + value + ",\");
    }



    return tempProperties;
}

Then it is going to be almost correct, except the save function takes the double backslash that is stored in the List, and turns it into 4 back slashes in the file! So you need to replace those with a single backslash. I did this like so:

try {
        config.save(new File(filePath));


        byte[] readIn = Files.readAllBytes(Paths.get(filePath));
        String replacer = new String(readIn, StandardCharsets.UTF_8).replace("\\\\", "\");

        BufferedWriter bw = new BufferedWriter(new OutputStreamWriter(new FileOutputStream(filePath, false), "UTF-8"));
        bw.write(replacer);
        bw.close();

} catch (ConfigurationException | IOException e) {
        e.printStackTrace();
}
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