在Java中将.prn文件转换为CSV文件格式

Question

need your help to convert prn file to csv file using java. Thank you so much.

Below is my prn file.

i would like to make it shows like this

Thank you so much.

Answer 1

In your example you have four entries as input, each in a row. In your result table they all are in one row. I assume the input describes a complete prn set. So if a file would contain n prn sets, it would have n * 4 rows.

To map the pm set to a csv file you have to

1. read in the entries from the input file
2. write a header row (with eight titles)
3. extract in each entry the relevant values
4. combine the extracted values from four entries in sequence to one csv row
5. write the row
6. repeat steps 3 to 5 as long as there are further entries

Here is my suggestion:

public class PrnToCsv {

    private static final String DILIM_PRN = " ";
    private static final String DILIM_CSV = ",";
    private static final Pattern PRN_SPLITTER = Pattern.compile(DILIM_PRN);

    public static void main(String[] args) throws URISyntaxException, IOException {
        List<String> inputLines = Files.readAllLines(new File("C://Temp//csv/input.prn").toPath());
        List<String[]> inputValuesInLines = inputLines.stream().map(l -> PRN_SPLITTER.split(l)).collect(Collectors.toList());

        try (BufferedWriter bw = Files.newBufferedWriter(new File("C://Temp//csv//output.csv").toPath())) {
            // header
            bw.append("POL1").append(DILIM_CSV).append("POL1_Time").append(DILIM_CSV).append("OLV1").append(DILIM_CSV).append("OLV1_Time").append(DILIM_CSV);
            bw.append("POL2").append(DILIM_CSV).append("POL2_Time").append(DILIM_CSV).append("OLV2").append(DILIM_CSV).append("OLV2_Time");
            bw.newLine();

            // data
            for (int i = 0; i + 3 < inputValuesInLines.size(); i = i + 4) {
                String[] firstValues = inputValuesInLines.get(i);
                bw.append(getId(firstValues)).append(DILIM_CSV).append(getDateTime(firstValues)).append(DILIM_CSV);
                String[] secondValues = inputValuesInLines.get(i + 1);
                bw.append(getId(secondValues)).append(DILIM_CSV).append(getDateTime(secondValues)).append(DILIM_CSV);
                String[] thirdValues = inputValuesInLines.get(i + 2);
                bw.append(getId(thirdValues)).append(DILIM_CSV).append(getDateTime(thirdValues)).append(DILIM_CSV);
                String[] fourthValues = inputValuesInLines.get(i + 3);
                bw.append(getId(fourthValues)).append(DILIM_CSV).append(getDateTime(fourthValues));
                bw.newLine();
            }
        }
    }

    public static String getId(String[] values) {
        return values[1];
    }

    public static String getDateTime(String[] values) {
        return values[2] + " " + values[3];
    }

}

Some remarks to the code:

• Using the nio-API you can read the whole file with one line of code.
• To extract the values of an entry line I used a Pattern to split the line into an array with each single word as a value.
• Then it is easy get the relevant values of an entry using the appropriate array indexes.
• To write the csv file line by line (without additional libs) you can use a BufferedWriter .
• The file you're writting to is a resource. It is recommended to use resources with the try-with-resource-statement .

I hope I could answer your question.