I want to copy files from one directory to another (subdirectory) using Java. I have a directory, dir, with text files. I iterate over the first 20 files in dir, and want to copy them to another directory in the dir directory, which I have created right before the iteration.
In the code, I want to copy the review (which represents the ith text file or review) to trainingDir. How can I do this? There seems not to be such a function (or I couldn't find). Thank you.
boolean success = false;
File[] reviews = dir.listFiles();
String trainingDir = dir.getAbsolutePath() + "/trainingData";
File trDir = new File(trainingDir);
success = trDir.mkdir();
for(int i = 1; i <= 20; i++) {
File review = reviews[i];
}
The NIO classes make this pretty simple.
following code to copy files from one directory to another
File destFile = new File(targetDir.getAbsolutePath() + File.separator
+ file.getName());
try {
showMessage("Copying " + file.getName());
in = new BufferedInputStream(new FileInputStream(file));
out = new BufferedOutputStream(new FileOutputStream(destFile));
int n;
while ((n = in.read()) != -1) {
out.write(n);
}
showMessage("Copied " + file.getName());
} catch (Exception e) {
showMessage("Cannot copy file " + file.getAbsolutePath());
} finally {
if (in != null)
try {
in.close();
} catch (Exception e) {
}
if (out != null)
try {
out.close();
} catch (Exception e) {
}
}
i use the following code to transfer a uploaded CommonMultipartFile to a folder and copy that file to a destination folder in webapps (i.e) web project folder,
String resourcepath = "C:/resources/images/" + commonsMultipartFile.getOriginalFilename();
File file = new File(resourcepath);
commonsMultipartFile.transferTo(file);
//Copy File to a Destination folder
File destinationDir = new File("C:/Tomcat/webapps/myProject/resources/images/");
FileUtils.copyFileToDirectory(file, destinationDir);
Inspired by Mohit's answer in this thread. Applicable only for Java 8.
The following can be used to copy everything recursively from one folder to another:
public static void main(String[] args) throws IOException {
Path source = Paths.get("/path/to/source/dir");
Path destination = Paths.get("/path/to/dest/dir");
List<Path> sources = Files.walk(source).collect(toList());
List<Path> destinations = sources.stream()
.map(source::relativize)
.map(destination::resolve)
.collect(toList());
for (int i = 0; i < sources.size(); i++) {
Files.copy(sources.get(i), destinations.get(i));
}
}
Stream-style FTW.
Upd 2019-06-10: important note - close the stream (e.g. using try-with-resource) acquired by Files.walk call. Thanks to @jannis for the point.
If you don't want to use external libraries and you want to use the java.io instead of java.nio classes, you can use this concise method to copy a folder and all its content:
/**
* Copies a folder and all its content to another folder. Do not include file separator at the end path of the folder destination.
* @param folderToCopy The folder and it's content that will be copied
* @param folderDestination The folder destination
*/
public static void copyFolder(File folderToCopy, File folderDestination) {
if(!folderDestination.isDirectory() || !folderToCopy.isDirectory())
throw new IllegalArgumentException("The folderToCopy and folderDestination must be directories");
folderDestination.mkdirs();
for(File fileToCopy : folderToCopy.listFiles()) {
File copiedFile = new File(folderDestination + File.separator + fileToCopy.getName());
try (FileInputStream fis = new FileInputStream(fileToCopy);
FileOutputStream fos = new FileOutputStream(copiedFile)) {
int read;
byte[] buffer = new byte[512];
while ((read = fis.read(buffer)) != -1) {
fos.write(buffer, 0, read);
}
} catch (FileNotFoundException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
} catch (Exception e) {
e.printStackTrace();
}
}
}
you use renameTo() – not obvious, I know ... but it's the Java equivalent of move ...
I provided an alternate solution without the need to use a third party, such as apache FileUtils. This can be done through the command line.
I tested this out on Windows and it works for me. A Linux solution follows.
Here I am utilizing Windows xcopy command to copy all files including subdirectories. The parameters that I pass are defined as per below.
My example(s) utilizes the ProcessBuilder class to construct a process to execute the copy(xcopy & cp) commands.
Windows:
String src = "C:\\srcDir";
String dest = "C:\\destDir";
List<String> cmd = Arrays.asList("xcopy", src, dest, "/e", "/i", "/h");
try {
Process proc = new ProcessBuilder(cmd).start();
BufferedReader inp = new BufferedReader(new InputStreamReader(proc.getInputStream()));
String line = null;
while ((line = inp.readLine()) != null) {
System.out.println(line);
}
} catch (IOException e) {
e.printStackTrace();
}
Linux:
String src = "srcDir/";
String dest = "~/destDir/";
List<String> cmd = Arrays.asList("/bin/bash", "-c", "cp", "r", src, dest);
try {
Process proc = new ProcessBuilder(cmd).start();
BufferedReader inp = new BufferedReader(new InputStreamReader(proc.getInputStream()));
String line = null;
while ((line = inp.readLine()) != null) {
System.out.println(line);
}
} catch (IOException e) {
e.printStackTrace();
}
Or a combo that can work on both Windows or Linux environments.
private static final String OS = System.getProperty("os.name");
private static String src = null;
private static String dest = null;
private static List<String> cmd = null;
public static void main(String[] args) {
if (OS.toLowerCase().contains("windows")) { // setup WINDOWS environment
src = "C:\\srcDir";
dest = "C:\\destDir";
cmd = Arrays.asList("xcopy", src, dest, "/e", "/i", "/h");
System.out.println("on: " + OS);
} else if (OS.toLowerCase().contains("linux")){ // setup LINUX environment
src = "srcDir/";
dest = "~/destDir/";
cmd = Arrays.asList("/bin/bash", "-c", "cp", "r", src, dest);
System.out.println("on: " + OS);
}
try {
Process proc = new ProcessBuilder(cmd).start();
BufferedReader inp = new BufferedReader(new InputStreamReader(proc.getInputStream()));
String line = null;
while ((line = inp.readLine()) != null) {
System.out.println(line);
}
} catch (IOException e) {
e.printStackTrace();
}
}
In Java 7, there is a standard method to copy files in java:
Files.copy.
It integrates with O/S native I/O for high performance.
See my A on Standard concise way to copy a file in Java? for a full description of usage.
File sourceFile = new File("C:\\Users\\Demo\\Downloads\\employee\\"+img);
File destinationFile = new File("\\images\\" + sourceFile.getName());
FileInputStream fileInputStream = new FileInputStream(sourceFile);
FileOutputStream fileOutputStream = new FileOutputStream(
destinationFile);
int bufferSize;
byte[] bufffer = new byte[512];
while ((bufferSize = fileInputStream.read(bufffer)) > 0) {
fileOutputStream.write(bufffer, 0, bufferSize);
}
fileInputStream.close();
fileOutputStream.close();
Best way as per my knowledge is as follows:
public static void main(String[] args) {
String sourceFolder = "E:\\Source";
String targetFolder = "E:\\Target";
File sFile = new File(sourceFolder);
File[] sourceFiles = sFile.listFiles();
for (File fSource : sourceFiles) {
File fTarget = new File(new File(targetFolder), fSource.getName());
copyFileUsingStream(fSource, fTarget);
deleteFiles(fSource);
}
}
private static void deleteFiles(File fSource) {
if(fSource.exists()) {
try {
FileUtils.forceDelete(fSource);
} catch (IOException e) {
e.printStackTrace();
}
}
}
private static void copyFileUsingStream(File source, File dest) {
InputStream is = null;
OutputStream os = null;
try {
is = new FileInputStream(source);
os = new FileOutputStream(dest);
byte[] buffer = new byte[1024];
int length;
while ((length = is.read(buffer)) > 0) {
os.write(buffer, 0, length);
}
} catch (Exception ex) {
System.out.println("Unable to copy file:" + ex.getMessage());
} finally {
try {
is.close();
os.close();
} catch (Exception ex) {
}
}
}
Apache commons FileUtils will be handy, if you want only to move files from the source to target directory rather than copy the whole directory, you can do:
for (File srcFile: srcDir.listFiles()) {
if (srcFile.isDirectory()) {
FileUtils.copyDirectoryToDirectory(srcFile, dstDir);
} else {
FileUtils.copyFileToDirectory(srcFile, dstDir);
}
}
If you want to skip directories, you can do:
for (File srcFile: srcDir.listFiles()) {
if (!srcFile.isDirectory()) {
FileUtils.copyFileToDirectory(srcFile, dstDir);
}
}
This prevents file from being corrupted!
Just download the following jar!
Jar File
Download Page
import org.springframework.util.FileCopyUtils;
private static void copyFile(File source, File dest) throws IOException {
//This is safe and don't corrupt files as FileOutputStream does
File src = source;
File destination = dest;
FileCopyUtils.copy(src, destm);
}
Use
org.apache.commons.io.FileUtils
It's so handy
import static java.nio.file.StandardCopyOption.*;
...
Files.copy(source, target, REPLACE_EXISTING);
Source: https://docs.oracle.com/javase/tutorial/essential/io/copy.html
Not even that complicated and no imports required in Java 7:
The renameTo( ) method changes the name of a file:
public boolean renameTo( File destination)
For example, to change the name of the file src.txt in the current working directory to dst.txt, you would write:
File src = new File(" src.txt"); File dst = new File(" dst.txt"); src.renameTo( dst);
That's it.
Reference:
Harold, Elliotte Rusty (2006-05-16). Java I/O (p. 393). O'Reilly Media. Kindle Edition.
Spring Framework has many similar util classes like Apache Commons Lang. So there is org.springframework.util.FileSystemUtils
File src = new File("/home/user/src");
File dest = new File("/home/user/dest");
FileSystemUtils.copyRecursively(src, dest);
File dir = new File("D:\\mital\\filestore");
File[] files = dir.listFiles(new File_Filter("*"+ strLine + "*.txt"));
for (File file : files){
System.out.println(file.getName());
try {
String sourceFile=dir+"\\"+file.getName();
String destinationFile="D:\\mital\\storefile\\"+file.getName();
FileInputStream fileInputStream = new FileInputStream(sourceFile);
FileOutputStream fileOutputStream = new FileOutputStream(
destinationFile);
int bufferSize;
byte[] bufffer = new byte[512];
while ((bufferSize = fileInputStream.read(bufffer)) > 0) {
fileOutputStream.write(bufffer, 0, bufferSize);
}
fileInputStream.close();
fileOutputStream.close();
} catch (Exception e) {
e.printStackTrace();
}
}
For now this should solve your problem
File source = new File("H:\\work-temp\\file");
File dest = new File("H:\\work-temp\\file2");
try {
FileUtils.copyDirectory(source, dest);
} catch (IOException e) {
e.printStackTrace();
}
FileUtils class from apache commons-io library, available since version 1.2.
Using third party tools instead of writing all utilities by ourself seems to be a better idea. It can save time and other valuable resources.
There is no file copy method in the Standard API (yet). Your options are:
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
public class CopyFiles {
private File targetFolder;
private int noOfFiles;
public void copyDirectory(File sourceLocation, String destLocation)
throws IOException {
targetFolder = new File(destLocation);
if (sourceLocation.isDirectory()) {
if (!targetFolder.exists()) {
targetFolder.mkdir();
}
String[] children = sourceLocation.list();
for (int i = 0; i < children.length; i++) {
copyDirectory(new File(sourceLocation, children[i]),
destLocation);
}
} else {
InputStream in = new FileInputStream(sourceLocation);
OutputStream out = new FileOutputStream(targetFolder + "\\"+ sourceLocation.getName(), true);
System.out.println("Destination Path ::"+targetFolder + "\\"+ sourceLocation.getName());
// Copy the bits from instream to outstream
byte[] buf = new byte[1024];
int len;
while ((len = in.read(buf)) > 0) {
out.write(buf, 0, len);
}
in.close();
out.close();
noOfFiles++;
}
}
public static void main(String[] args) throws IOException {
File srcFolder = new File("C:\\sourceLocation\\");
String destFolder = new String("C:\\targetLocation\\");
CopyFiles cf = new CopyFiles();
cf.copyDirectory(srcFolder, destFolder);
System.out.println("No Of Files got Retrieved from Source ::"+cf.noOfFiles);
System.out.println("Successfully Retrieved");
}
}
You can workaround with copy the source file to a new file and delete the original.
public class MoveFileExample {
public static void main(String[] args) {
InputStream inStream = null;
OutputStream outStream = null;
try {
File afile = new File("C:\\folderA\\Afile.txt");
File bfile = new File("C:\\folderB\\Afile.txt");
inStream = new FileInputStream(afile);
outStream = new FileOutputStream(bfile);
byte[] buffer = new byte[1024];
int length;
//copy the file content in bytes
while ((length = inStream.read(buffer)) > 0) {
outStream.write(buffer, 0, length);
}
inStream.close();
outStream.close();
//delete the original file
afile.delete();
System.out.println("File is copied successful!");
} catch(IOException e) {
e.printStackTrace();
}
}
}
Java 8
Path sourcepath = Paths.get("C:\\data\\temp\\mydir");
Path destinationepath = Paths.get("C:\\data\\temp\\destinationDir");
Files.walk(sourcepath)
.forEach(source -> copy(source, destinationepath.resolve(sourcepath.relativize(source))));
Copy Method
static void copy(Path source, Path dest) {
try {
Files.copy(source, dest, StandardCopyOption.REPLACE_EXISTING);
} catch (Exception e) {
throw new RuntimeException(e.getMessage(), e);
}
}
here is simply a java code to copy data from one folder to another, you have to just give the input of the source and destination.
import java.io.*;
public class CopyData {
static String source;
static String des;
static void dr(File fl,boolean first) throws IOException
{
if(fl.isDirectory())
{
createDir(fl.getPath(),first);
File flist[]=fl.listFiles();
for(int i=0;i<flist.length;i++)
{
if(flist[i].isDirectory())
{
dr(flist[i],false);
}
else
{
copyData(flist[i].getPath());
}
}
}
else
{
copyData(fl.getPath());
}
}
private static void copyData(String name) throws IOException {
int i;
String str=des;
for(i=source.length();i<name.length();i++)
{
str=str+name.charAt(i);
}
System.out.println(str);
FileInputStream fis=new FileInputStream(name);
FileOutputStream fos=new FileOutputStream(str);
byte[] buffer = new byte[1024];
int noOfBytes = 0;
while ((noOfBytes = fis.read(buffer)) != -1) {
fos.write(buffer, 0, noOfBytes);
}
}
private static void createDir(String name, boolean first) {
int i;
if(first==true)
{
for(i=name.length()-1;i>0;i--)
{
if(name.charAt(i)==92)
{
break;
}
}
for(;i<name.length();i++)
{
des=des+name.charAt(i);
}
}
else
{
String str=des;
for(i=source.length();i<name.length();i++)
{
str=str+name.charAt(i);
}
(new File(str)).mkdirs();
}
}
public static void main(String args[]) throws IOException
{
BufferedReader br=new BufferedReader(new InputStreamReader(System.in));
System.out.println("program to copy data from source to destination \n");
System.out.print("enter source path : ");
source=br.readLine();
System.out.print("enter destination path : ");
des=br.readLine();
long startTime = System.currentTimeMillis();
dr(new File(source),true);
long endTime = System.currentTimeMillis();
long time=endTime-startTime;
System.out.println("\n\n Time taken = "+time+" mili sec");
}
}
this a working code for what you want..let me know if it helped
You can use the following code to copy files from one directory to another
// parent folders of dest must exist before calling this function
public static void copyTo( File src, File dest ) throws IOException {
// recursively copy all the files of src folder if src is a directory
if( src.isDirectory() ) {
// creating parent folders where source files is to be copied
dest.mkdirs();
for( File sourceChild : src.listFiles() ) {
File destChild = new File( dest, sourceChild.getName() );
copyTo( sourceChild, destChild );
}
}
// copy the source file
else {
InputStream in = new FileInputStream( src );
OutputStream out = new FileOutputStream( dest );
writeThrough( in, out );
in.close();
out.close();
}
}
File file = fileChooser.getSelectedFile();
String selected = fc.getSelectedFile().getAbsolutePath();
File srcDir = new File(selected);
FileInputStream fii;
FileOutputStream fio;
try {
fii = new FileInputStream(srcDir);
fio = new FileOutputStream("C:\\LOvE.txt");
byte [] b=new byte[1024];
int i=0;
try {
while ((fii.read(b)) > 0)
{
System.out.println(b);
fio.write(b);
}
fii.close();
fio.close();
If you want to copy a file and not move it you can code like this.
private static void copyFile(File sourceFile, File destFile)
throws IOException {
if (!sourceFile.exists()) {
return;
}
if (!destFile.exists()) {
destFile.createNewFile();
}
FileChannel source = null;
FileChannel destination = null;
source = new FileInputStream(sourceFile).getChannel();
destination = new FileOutputStream(destFile).getChannel();
if (destination != null && source != null) {
destination.transferFrom(source, 0, source.size());
}
if (source != null) {
source.close();
}
if (destination != null) {
destination.close();
}
}
You can use the following code to copy files from one directory to another
public static void copyFile(File sourceFile, File destFile) throws IOException {
InputStream in = null;
OutputStream out = null;
try {
in = new FileInputStream(sourceFile);
out = new FileOutputStream(destFile);
byte[] buffer = new byte[1024];
int length;
while ((length = in.read(buffer)) > 0) {
out.write(buffer, 0, length);
}
} catch(Exception e){
e.printStackTrace();
}
finally {
in.close();
out.close();
}
}
Following recursive function I have written, if it helps anyone. It will copy all the files inside sourcedirectory to destinationDirectory.
example:
rfunction("D:/MyDirectory", "D:/MyDirectoryNew", "D:/MyDirectory");
public static void rfunction(String sourcePath, String destinationPath, String currentPath) {
File file = new File(currentPath);
FileInputStream fi = null;
FileOutputStream fo = null;
if (file.isDirectory()) {
String[] fileFolderNamesArray = file.list();
File folderDes = new File(destinationPath);
if (!folderDes.exists()) {
folderDes.mkdirs();
}
for (String fileFolderName : fileFolderNamesArray) {
rfunction(sourcePath, destinationPath + "/" + fileFolderName, currentPath + "/" + fileFolderName);
}
} else {
try {
File destinationFile = new File(destinationPath);
fi = new FileInputStream(file);
fo = new FileOutputStream(destinationPath);
byte[] buffer = new byte[1024];
int ind = 0;
while ((ind = fi.read(buffer))>0) {
fo.write(buffer, 0, ind);
}
} catch (FileNotFoundException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
finally {
if (null != fi) {
try {
fi.close();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
if (null != fo) {
try {
fo.close();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}
}
}
The example below from Java Tips is rather straight forward. I have since switched to Groovy for operations dealing with the file system - much easier and elegant. But here is the Java Tips one I used in the past. It lacks the robust exception handling that is required to make it fool-proof.
public void copyDirectory(File sourceLocation , File targetLocation)
throws IOException {
if (sourceLocation.isDirectory()) {
if (!targetLocation.exists()) {
targetLocation.mkdir();
}
String[] children = sourceLocation.list();
for (int i=0; i<children.length; i++) {
copyDirectory(new File(sourceLocation, children[i]),
new File(targetLocation, children[i]));
}
} else {
InputStream in = new FileInputStream(sourceLocation);
OutputStream out = new FileOutputStream(targetLocation);
// Copy the bits from instream to outstream
byte[] buf = new byte[1024];
int len;
while ((len = in.read(buf)) > 0) {
out.write(buf, 0, len);
}
in.close();
out.close();
}
}
Below is Brian's modified code which copies files from source location to destination location.
public class CopyFiles {
public static void copyFiles(File sourceLocation , File targetLocation)
throws IOException {
if (sourceLocation.isDirectory()) {
if (!targetLocation.exists()) {
targetLocation.mkdir();
}
File[] files = sourceLocation.listFiles();
for(File file:files){
InputStream in = new FileInputStream(file);
OutputStream out = new FileOutputStream(targetLocation+"/"+file.getName());
// Copy the bits from input stream to output stream
byte[] buf = new byte[1024];
int len;
while ((len = in.read(buf)) > 0) {
out.write(buf, 0, len);
}
in.close();
out.close();
}
}
}
You seem to be looking for the simple solution (a good thing). I recommend using Apache Common's FileUtils.copyDirectory:
Copies a whole directory to a new location preserving the file dates.
This method copies the specified directory and all its child directories and files to the specified destination. The destination is the new location and name of the directory.
The destination directory is created if it does not exist. If the destination directory did exist, then this method merges the source with the destination, with the source taking precedence.
Your code could like nice and simple like this:
File trgDir = new File("/tmp/myTarget/");
File srcDir = new File("/tmp/mySource/");
FileUtils.copyDirectory(srcDir, trgDir);
apache commons Fileutils is handy. you can do below activities.
copying file from one directory to another directory.
use copyFileToDirectory(File srcFile, File destDir)
copying directory from one directory to another directory.
use copyDirectory(File srcDir, File destDir)
copying contents of one file to another
use static void copyFile(File srcFile, File destFile)
Copy file from one directory to another directory...
FileChannel source=new FileInputStream(new File("source file path")).getChannel();
FileChannel desti=new FileOutputStream(new File("destination file path")).getChannel();
desti.transferFrom(source, 0, source.size());
source.close();
desti.close();
Source: Stackoverflow.com