how to sort an arrayList containing files based on extentions

Question

File [] templatesList = templateFileList.toArray(new File[0] );
Arrays.sort(templatesList,ExtensionFileComparator.EXTENSION_INSENSITIVE_REVERSE);

templatesList contains files like

app.vm
app.1.ivm
app.2.ivm
mart.ivm
mart.vm

First reverse sort based on last extension, then sort based on basename, then sort numbers. After sorting, expected output is

app.vm
mart.vm
app.1.ivm
app.2.ivm
mart.ivm

My Code:

    File [] templatesList = templateFileList.toArray(new File[0] );
    List <File> tempList = Arrays.asList(templatesList);
    tempList.stream().sorted(ExtensionFileComparator.EXTENSION_INSENSITIVE_REVERSE.
            thenComparing(NameFileComparator.NAME_INSENSITIVE_COMPARATOR));     

        List <File> templateFileList1 = new ArrayList(Arrays.asList(templatesList));
        Collections.sort(templateFileList1, new Comparator <File>() {

            @Override
            public int compare(File f1, File f2) {
                return Integer.parseInt(FilenameUtils.getExtension(FilenameUtils.getBaseName(f1.toString())))-
                        Integer.parseInt(FilenameUtils.getExtension(FilenameUtils.getBaseName(f2.toString())));
            }
        });

Have you tried something yet?

Tim Biegeleisen
– Tim Biegeleisen

2018-04-04 10:49:41 +00:00
Commented Apr 4, 2018 at 10:49 — Tim Biegeleisen
– Tim Biegeleisen, Commented Apr 4, 2018 at 10:49
yes i tried. i added my code now. can you please check now

RAJ METRE
– RAJ METRE

2018-04-04 11:03:26 +00:00
Commented Apr 4, 2018 at 11:03 — RAJ METRE
– RAJ METRE, Commented Apr 4, 2018 at 11:03

davidxxx · Accepted Answer · 2018-04-04 10:56:16Z

1

You could mix ExtensionFileComparator and NameFileComparator from Apache commons Comparators.
With Java 8 :

Arrays.sort(templatesList, ExtensionFileComparator.EXTENSION_INSENSITIVE_REVERSE
              .thenComparing(NameFileComparator.NAME_INSENSITIVE_COMPARATOR));

Or write it without any API with a little more boiler plate code.

answered Apr 4, 2018 at 10:56

davidxxx

132k23 gold badges231 silver badges228 bronze badges

Sign up to request clarification or add additional context in comments.

Comments

RAJ METRE · Accepted Answer · 2018-04-05 12:56:03Z

if someone looking for answer

File [] templatesList = templateFileList.toArray(new File[0] );
    Arrays.sort(templatesList, ExtensionFileComparator.EXTENSION_INSENSITIVE_REVERSE
            .thenComparing(NameFileComparator.NAME_INSENSITIVE_COMPARATOR).thenComparing(new Comparator <File>() {
                @Override
                public int compare(File f1, File f2) {
                    String file1 = FilenameUtils.getBaseName(f1.toString());
                    String file2 = FilenameUtils.getBaseName(f2.toString());

                    String ext1 = FilenameUtils.getExtension(file1);
                    String ext2 = FilenameUtils.getExtension(file2);

                    if ((StringUtils.isNumericSpace(ext1)) &&(StringUtils.isNumericSpace(ext2))) {
                        int t1= Integer.parseInt(ext1);
                        int t2= Integer.parseInt(ext2);
                        return t1-t2;
                    }
                    else {
                    return 0;
                    }
                }                   
            }));

Collectives™ on Stack Overflow

how to sort an arrayList containing files based on extentions

2 Answers 2

Comments

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

Comments

Comments

Your Answer

Sign up or log in

Post as a guest

Related