Question

I know how to copy a file from one directory to another, what I would like help on is copy a file with .jpg or .doc extension.

So for example.

Copy all files from D:/Pictures/Holidays

Scanning all folders in the above path and transfer all jpg’s to a destination provided.

Answer 1

This works, but the file ‘copy(File file, File outputFolder)’ method could be enhanced for large files:

package net.bpfurtado.copyfiles;

import java.io.File;
import java.io.FileFilter;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.InputStream;
import java.io.OutputStream;

public class CopyFilesFromType
{
    public static void main(String[] args)
    {
        new CopyFilesFromType().copy("jpg", "C:\\Users\\BrunoFurtado\\Pictures", "c:/temp/photos");
    }

    private FileTypeOrFolderFilter filter = null;

    private void copy(final String fileType, String fromPath, String outputPath)
    {
        filter = new FileTypeOrFolderFilter(fileType);
        File currentFolder = new File(fromPath);
        File outputFolder = new File(outputPath);
        scanFolder(fileType, currentFolder, outputFolder);
    }

    private void scanFolder(final String fileType, File currentFolder, File outputFolder)
    {
        System.out.println("Scanning folder [" + currentFolder + "]...");
        File[] files = currentFolder.listFiles(filter);
        for (File file : files) {
            if (file.isDirectory()) {
                scanFolder(fileType, file, outputFolder);
            } else {
                copy(file, outputFolder);
            }
        }
    }

    private void copy(File file, File outputFolder)
    {
        try {
            System.out.println("\tCopying [" + file + "] to folder [" + outputFolder + "]...");
            InputStream input = new FileInputStream(file);
            OutputStream out = new FileOutputStream(new File(outputFolder + File.separator + file.getName()));
            byte data[] = new byte[input.available()];
            input.read(data);
            out.write(data);
            out.flush();
            out.close();
            input.close();
        } catch (Exception e) {
            throw new RuntimeException(e);
        }
    }

    private final class FileTypeOrFolderFilter implements FileFilter
    {
        private final String fileType;

        private FileTypeOrFolderFilter(String fileType)
        {
            this.fileType = fileType;
        }

        public boolean accept(File pathname)
        {
            return pathname.getName().endsWith("." + fileType) || pathname.isDirectory();
        }
    }
}