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How to read all the files in a folder through Java? It doesn't matter which API.
public void listFilesForFolder(final File folder) {
for (final File fileEntry : folder.listFiles()) {
if (fileEntry.isDirectory()) {
listFilesForFolder(fileEntry);
} else {
System.out.println(fileEntry.getName());
}
}
}
final File folder = new File("/home/you/Desktop");
listFilesForFolder(folder);
Files.walk API is available from Java 8.
try (Stream<Path> paths = Files.walk(Paths.get("/home/you/Desktop"))) {
paths
.filter(Files::isRegularFile)
.forEach(System.out::println);
}
The example uses try-with-resources pattern recommended in API guide. It ensures that no matter circumstances the stream will be closed.
File folder = new File("/Users/you/folder/");
File[] listOfFiles = folder.listFiles();
for (File file : listOfFiles) {
if (file.isFile()) {
System.out.println(file.getName());
}
}
In Java 8 you can do this
Files.walk(Paths.get("/path/to/folder"))
.filter(Files::isRegularFile)
.forEach(System.out::println);
which will print all files in a folder while excluding all directories. If you need a list, the following will do:
Files.walk(Paths.get("/path/to/folder"))
.filter(Files::isRegularFile)
.collect(Collectors.toList())
If you want to return List<File> instead of List<Path> just map it:
List<File> filesInFolder = Files.walk(Paths.get("/path/to/folder"))
.filter(Files::isRegularFile)
.map(Path::toFile)
.collect(Collectors.toList());
You also need to make sure to close the stream! Otherwise you might run into an exception telling you that too many files are open. Read here for more information.
All of the answers on this topic that make use of the new Java 8 functions are neglecting to close the stream. The example in the accepted answer should be:
try (Stream<Path> filePathStream=Files.walk(Paths.get("/home/you/Desktop"))) {
filePathStream.forEach(filePath -> {
if (Files.isRegularFile(filePath)) {
System.out.println(filePath);
}
});
}
From the javadoc of the Files.walk method:
The returned stream encapsulates one or more DirectoryStreams. If
timely disposal of file system resources is required, the
try-with-resources construct should be used to ensure that the
stream's close method is invoked after the stream operations are completed.
One remark according to get all files in the directory.
The method Files.walk(path) will return all files by walking the file tree rooted at the given started file.
For instance, there is the next file tree:
\---folder
| file1.txt
| file2.txt
|
\---subfolder
file3.txt
file4.txt
Using the java.nio.file.Files.walk(Path):
Files.walk(Paths.get("folder"))
.filter(Files::isRegularFile)
.forEach(System.out::println);
Gives the following result:
folder\file1.txt
folder\file2.txt
folder\subfolder\file3.txt
folder\subfolder\file4.txt
To get all files only in the current directory use the java.nio.file.Files.list(Path):
Files.list(Paths.get("folder"))
.filter(Files::isRegularFile)
.forEach(System.out::println);
Result:
folder\file1.txt
folder\file2.txt
import java.io.File;
public class ReadFilesFromFolder {
public static File folder = new File("C:/Documents and Settings/My Documents/Downloads");
static String temp = "";
public static void main(String[] args) {
// TODO Auto-generated method stub
System.out.println("Reading files under the folder "+ folder.getAbsolutePath());
listFilesForFolder(folder);
}
public static void listFilesForFolder(final File folder) {
for (final File fileEntry : folder.listFiles()) {
if (fileEntry.isDirectory()) {
// System.out.println("Reading files under the folder "+folder.getAbsolutePath());
listFilesForFolder(fileEntry);
} else {
if (fileEntry.isFile()) {
temp = fileEntry.getName();
if ((temp.substring(temp.lastIndexOf('.') + 1, temp.length()).toLowerCase()).equals("txt"))
System.out.println("File= " + folder.getAbsolutePath()+ "\\" + fileEntry.getName());
}
}
}
}
}
In Java 7 and higher you can use listdir
Path dir = ...;
try (DirectoryStream<Path> stream = Files.newDirectoryStream(dir)) {
for (Path file: stream) {
System.out.println(file.getFileName());
}
} catch (IOException | DirectoryIteratorException x) {
// IOException can never be thrown by the iteration.
// In this snippet, it can only be thrown by newDirectoryStream.
System.err.println(x);
}
You can also create a filter that can then be passed into the newDirectoryStream method above
DirectoryStream.Filter<Path> filter = new DirectoryStream.Filter<Path>() {
public boolean accept(Path file) throws IOException {
try {
return (Files.isRegularFile(path));
} catch (IOException x) {
// Failed to determine if it's a file.
System.err.println(x);
return false;
}
}
};
For other filtering examples, [see documentation].(http://docs.oracle.com/javase/tutorial/essential/io/dirs.html#glob)
private static final String ROOT_FILE_PATH="/";
File f=new File(ROOT_FILE_PATH);
File[] allSubFiles=f.listFiles();
for (File file : allSubFiles) {
if(file.isDirectory())
{
System.out.println(file.getAbsolutePath()+" is directory");
//Steps for directory
}
else
{
System.out.println(file.getAbsolutePath()+" is file");
//steps for files
}
}
Just walk through all Files using Files.walkFileTree (Java 7)
Files.walkFileTree(Paths.get(dir), new SimpleFileVisitor<Path>() {
#Override
public FileVisitResult visitFile(Path file, BasicFileAttributes attrs) throws IOException {
System.out.println("file: " + file);
return FileVisitResult.CONTINUE;
}
});
If you want more options, you can use this function which aims to populate an arraylist of files present in a folder. Options are : recursivility and pattern to match.
public static ArrayList<File> listFilesForFolder(final File folder,
final boolean recursivity,
final String patternFileFilter) {
// Inputs
boolean filteredFile = false;
// Ouput
final ArrayList<File> output = new ArrayList<File> ();
// Foreach elements
for (final File fileEntry : folder.listFiles()) {
// If this element is a directory, do it recursivly
if (fileEntry.isDirectory()) {
if (recursivity) {
output.addAll(listFilesForFolder(fileEntry, recursivity, patternFileFilter));
}
}
else {
// If there is no pattern, the file is correct
if (patternFileFilter.length() == 0) {
filteredFile = true;
}
// Otherwise we need to filter by pattern
else {
filteredFile = Pattern.matches(patternFileFilter, fileEntry.getName());
}
// If the file has a name which match with the pattern, then add it to the list
if (filteredFile) {
output.add(fileEntry);
}
}
}
return output;
}
Best, Adrien
File directory = new File("/user/folder");
File[] myarray;
myarray=new File[10];
myarray=directory.listFiles();
for (int j = 0; j < myarray.length; j++)
{
File path=myarray[j];
FileReader fr = new FileReader(path);
BufferedReader br = new BufferedReader(fr);
String s = "";
while (br.ready()) {
s += br.readLine() + "\n";
}
}
nice usage of java.io.FileFilter as seen on https://stackoverflow.com/a/286001/146745
File fl = new File(dir);
File[] files = fl.listFiles(new FileFilter() {
public boolean accept(File file) {
return file.isFile();
}
});
static File mainFolder = new File("Folder");
public static void main(String[] args) {
lf.getFiles(lf.mainFolder);
}
public void getFiles(File f) {
File files[];
if (f.isFile()) {
String name=f.getName();
} else {
files = f.listFiles();
for (int i = 0; i < files.length; i++) {
getFiles(files[i]);
}
}
}
I think this is good way to read all the files in a folder and sub folder's
private static void addfiles (File input,ArrayList<File> files)
{
if(input.isDirectory())
{
ArrayList <File> path = new ArrayList<File>(Arrays.asList(input.listFiles()));
for(int i=0 ; i<path.size();++i)
{
if(path.get(i).isDirectory())
{
addfiles(path.get(i),files);
}
if(path.get(i).isFile())
{
files.add(path.get(i));
}
}
}
if(input.isFile())
{
files.add(input);
}
}
Simple example that works with Java 1.7 to recursively list files in directories specified on the command-line:
import java.io.File;
public class List {
public static void main(String[] args) {
for (String f : args) {
listDir(f);
}
}
private static void listDir(String dir) {
File f = new File(dir);
File[] list = f.listFiles();
if (list == null) {
return;
}
for (File entry : list) {
System.out.println(entry.getName());
if (entry.isDirectory()) {
listDir(entry.getAbsolutePath());
}
}
}
}
While I do agree with Rich, Orian and the rest for using:
final File keysFileFolder = new File(<path>);
File[] fileslist = keysFileFolder.listFiles();
if(fileslist != null)
{
//Do your thing here...
}
for some reason all the examples here uses absolute path (i.e. all the way from root, or, say, drive letter (C:\) for windows..)
I'd like to add that it is possible to use relative path as-well.
So, if you're pwd (current directory/folder) is folder1 and you want to parse folder1/subfolder, you simply write (in the code above instead of ):
final File keysFileFolder = new File("subfolder");
Java 8 Files.walk(..) is good when you are soore it will not throw Avoid Java 8 Files.walk(..) termination cause of ( java.nio.file.AccessDeniedException ) .
Here is a safe solution , not though so elegant as Java 8Files.walk(..) :
int[] count = {0};
try {
Files.walkFileTree(Paths.get(dir.getPath()), new HashSet<FileVisitOption>(Arrays.asList(FileVisitOption.FOLLOW_LINKS)),
Integer.MAX_VALUE, new SimpleFileVisitor<Path>() {
#Override
public FileVisitResult visitFile(Path file , BasicFileAttributes attrs) throws IOException {
System.out.printf("Visiting file %s\n", file);
++count[0];
return FileVisitResult.CONTINUE;
}
#Override
public FileVisitResult visitFileFailed(Path file , IOException e) throws IOException {
System.err.printf("Visiting failed for %s\n", file);
return FileVisitResult.SKIP_SUBTREE;
}
#Override
public FileVisitResult preVisitDirectory(Path dir , BasicFileAttributes attrs) throws IOException {
System.out.printf("About to visit directory %s\n", dir);
return FileVisitResult.CONTINUE;
}
});
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
void getFiles(){
String dirPath = "E:/folder_name";
File dir = new File(dirPath);
String[] files = dir.list();
if (files.length == 0) {
System.out.println("The directory is empty");
} else {
for (String aFile : files) {
System.out.println(aFile);
}
}
}
package com;
import java.io.File;
/**
*
* #author ?Mukesh
*/
public class ListFiles {
static File mainFolder = new File("D:\\Movies");
public static void main(String[] args)
{
ListFiles lf = new ListFiles();
lf.getFiles(lf.mainFolder);
long fileSize = mainFolder.length();
System.out.println("mainFolder size in bytes is: " + fileSize);
System.out.println("File size in KB is : " + (double)fileSize/1024);
System.out.println("File size in MB is :" + (double)fileSize/(1024*1024));
}
public void getFiles(File f){
File files[];
if(f.isFile())
System.out.println(f.getAbsolutePath());
else{
files = f.listFiles();
for (int i = 0; i < files.length; i++) {
getFiles(files[i]);
}
}
}
}
Just to expand on the accepted answer I store the filenames to an ArrayList (instead of just dumping them to System.out.println) I created a helper class "MyFileUtils" so it could be imported by other projects:
class MyFileUtils {
public static void loadFilesForFolder(final File folder, List<String> fileList){
for (final File fileEntry : folder.listFiles()) {
if (fileEntry.isDirectory()) {
loadFilesForFolder(fileEntry, fileList);
} else {
fileList.add( fileEntry.getParent() + File.separator + fileEntry.getName() );
}
}
}
}
I added the full path to the file name.
You would use it like this:
import MyFileUtils;
List<String> fileList = new ArrayList<String>();
final File folder = new File("/home/you/Desktop");
MyFileUtils.loadFilesForFolder(folder, fileList);
// Dump file list values
for (String fileName : fileList){
System.out.println(fileName);
}
The ArrayList is passed by "value", but the value is used to point to the same ArrayList object living in the JVM Heap. In this way, each recursion call adds filenames to the same ArrayList (we are NOT creating a new ArrayList on each recursive call).
There are many good answers above, here's a different approach: In a maven project, everything you put in the resources folder is copied by default in the target/classes folder. To see what is available at runtime
ClassLoader contextClassLoader =
Thread.currentThread().getContextClassLoader();
URL resource = contextClassLoader.getResource("");
File file = new File(resource.toURI());
File[] files = file.listFiles();
for (File f : files) {
System.out.println(f.getName());
}
Now to get the files from a specific folder, let's say you have a folder called 'res' in your resources folder, just replace:
URL resource = contextClassLoader.getResource("res");
If you want to have access in your com.companyName package then:
contextClassLoader.getResource("com.companyName");
You can put the file path to argument and create a list with all the filepaths and not put it the list manually. Then use a for loop and a reader. Example for txt files:
public static void main(String[] args) throws IOException{
File[] files = new File(args[0].replace("\\", "\\\\")).listFiles(new FilenameFilter() { #Override public boolean accept(File dir, String name) { return name.endsWith(".txt"); } });
ArrayList<String> filedir = new ArrayList<String>();
String FILE_TEST = null;
for (i=0; i<files.length; i++){
filedir.add(files[i].toString());
CSV_FILE_TEST=filedir.get(i)
try(Reader testreader = Files.newBufferedReader(Paths.get(FILE_TEST));
){
//write your stuff
}}}
package com.commandline.folder;
import java.io.File;
import java.nio.file.Files;
import java.nio.file.Path;
import java.nio.file.Paths;
import java.util.stream.Stream;
public class FolderReadingDemo {
public static void main(String[] args) {
String str = args[0];
final File folder = new File(str);
// listFilesForFolder(folder);
listFilesForFolder(str);
}
public static void listFilesForFolder(String str) {
try (Stream<Path> paths = Files.walk(Paths.get(str))) {
paths.filter(Files::isRegularFile).forEach(System.out::println);
} catch (Exception e) {
e.printStackTrace();
}
}
public static void listFilesForFolder(final File folder) {
for (final File fileEntry : folder.listFiles()) {
if (fileEntry.isDirectory()) {
listFilesForFolder(fileEntry);
} else {
System.out.println(fileEntry.getName());
}
}
}
}
We can use org.apache.commons.io.FileUtils, use listFiles() mehtod to read all the files in a given folder.
eg:
FileUtils.listFiles(directory, new String[] {"ext1", "ext2"}, true)
This read all the files in the given directory with given extensions, we can pass multiple extensions in the array and read recursively within the folder(true parameter).
public static List<File> files(String dirname) {
if (dirname == null) {
return Collections.emptyList();
}
File dir = new File(dirname);
if (!dir.exists()) {
return Collections.emptyList();
}
if (!dir.isDirectory()) {
return Collections.singletonList(file(dirname));
}
return Arrays.stream(Objects.requireNonNull(dir.listFiles()))
.collect(Collectors.toList());
}
import java.io.File;
import java.util.ArrayList;
import java.util.List;
public class AvoidNullExp {
public static void main(String[] args) {
List<File> fileList =new ArrayList<>();
final File folder = new File("g:/master");
new AvoidNullExp().listFilesForFolder(folder, fileList);
}
public void listFilesForFolder(final File folder,List<File> fileList) {
File[] filesInFolder = folder.listFiles();
if (filesInFolder != null) {
for (final File fileEntry : filesInFolder) {
if (fileEntry.isDirectory()) {
System.out.println("DIR : "+fileEntry.getName());
listFilesForFolder(fileEntry,fileList);
} else {
System.out.println("FILE : "+fileEntry.getName());
fileList.add(fileEntry);
}
}
}
}
}
list down files from Test folder present inside class path
import java.io.File;
import java.io.IOException;
public class Hello {
public static void main(final String[] args) throws IOException {
System.out.println("List down all the files present on the server directory");
File file1 = new File("/prog/FileTest/src/Test");
File[] files = file1.listFiles();
if (null != files) {
for (int fileIntList = 0; fileIntList < files.length; fileIntList++) {
String ss = files[fileIntList].toString();
if (null != ss && ss.length() > 0) {
System.out.println("File: " + (fileIntList + 1) + " :" + ss.substring(ss.lastIndexOf("\\") + 1, ss.length()));
}
}
}
}
}
/**
* Function to read all mp3 files from sdcard and store the details in an
* ArrayList
*/
public ArrayList<HashMap<String, String>> getPlayList()
{
ArrayList<HashMap<String, String>> songsList=new ArrayList<>();
File home = new File(MEDIA_PATH);
if (home.listFiles(new FileExtensionFilter()).length > 0) {
for (File file : home.listFiles(new FileExtensionFilter())) {
HashMap<String, String> song = new HashMap<String, String>();
song.put(
"songTitle",
file.getName().substring(0,
(file.getName().length() - 4)));
song.put("songPath", file.getPath());
// Adding each song to SongList
songsList.add(song);
}
}
// return songs list array
return songsList;
}
/**
* Class to filter files which have a .mp3 extension
* */
class FileExtensionFilter implements FilenameFilter
{
#Override
public boolean accept(File dir, String name) {
return (name.endsWith(".mp3") || name.endsWith(".MP3"));
}
}
You can filter any textfiles or any other extension ..just replace it with .MP3
This will Read Specified file extension files in given path(looks sub folders also)
public static Map<String,List<File>> getFileNames(String
dirName,Map<String,List<File>> filesContainer,final String fileExt){
String dirPath = dirName;
List<File>files = new ArrayList<>();
Map<String,List<File>> completeFiles = filesContainer;
if(completeFiles == null) {
completeFiles = new HashMap<>();
}
File file = new File(dirName);
FileFilter fileFilter = new FileFilter() {
#Override
public boolean accept(File file) {
boolean acceptFile = false;
if(file.isDirectory()) {
acceptFile = true;
}else if (file.getName().toLowerCase().endsWith(fileExt))
{
acceptFile = true;
}
return acceptFile;
}
};
for(File dirfile : file.listFiles(fileFilter)) {
if(dirfile.isFile() &&
dirfile.getName().toLowerCase().endsWith(fileExt)) {
files.add(dirfile);
}else if(dirfile.isDirectory()) {
if(!files.isEmpty()) {
completeFiles.put(dirPath, files);
}
getFileNames(dirfile.getAbsolutePath(),completeFiles,fileExt);
}
}
if(!files.isEmpty()) {
completeFiles.put(dirPath, files);
}
return completeFiles;
}
This will work fine:
private static void addfiles(File inputValVal, ArrayList<File> files)
{
if(inputVal.isDirectory())
{
ArrayList <File> path = new ArrayList<File>(Arrays.asList(inputVal.listFiles()));
for(int i=0; i<path.size(); ++i)
{
if(path.get(i).isDirectory())
{
addfiles(path.get(i),files);
}
if(path.get(i).isFile())
{
files.add(path.get(i));
}
}
/* Optional : if you need to have the counts of all the folders and files you can create 2 global arrays
and store the results of the above 2 if loops inside these arrays */
}
if(inputVal.isFile())
{
files.add(inputVal);
}
}
I am working on an application which will download 3rd party dependencies to a particular folder and then execute dependency check on it. The files downloaded can be of any type, they can be zip, jar or may b a folder. I am trying to find a code example but nothing seems to work for me. I tried NIO in java but that seems to work only for writing to a particular file not folder. Below is code where I used NIO
// Checking If The File Exists At The Specified Location Or Not
Path filePathObj = Paths.get(filePath);
boolean fileExists = Files.exists(filePathObj);
if(fileExists) {
try {
urlObj = new URL(sampleUrl);
rbcObj = Channels.newChannel(urlObj.openStream());
fOutStream = new FileOutputStream(filePath);
fOutStream.getChannel().transferFrom(rbcObj, 0, Long.MAX_VALUE);
System.out.println("! File Successfully Downloaded From The Url !");
} catch (IOException ioExObj) {
System.out.println("Problem Occured While Downloading The File= " + ioExObj.getMessage());
} finally {
try {
if(fOutStream != null){
fOutStream.close();
}
if(rbcObj != null) {
rbcObj.close();
}
} catch (IOException ioExObj) {
System.out.println("Problem Occured While Closing The Object= " + ioExObj.getMessage());
}
}
} else {
System.out.println("File Not Present! Please Check!");
}```
public Class CopyAndWrite {
public static final String SOURCES = "C:\\Users\\Administrator\\Desktop\\resources";
public static final String TARGET = "C:\\Users\\Administrator\\Desktop\\111";
public static void main (String[]args) throws IOException {
Path startingDir = Paths.get(SOURCES);
Files.walkFileTree(startingDir, new FindJavaVisitor());
}
private static class FindJavaVisitor extends SimpleFileVisitor<Path> {
#Override
public FileVisitResult preVisitDirectory(Path dir, BasicFileAttributes attrs) throws IOException {
if (!StringUtils.equals(dir.toString(), SOURCES)) {
Path targetPath = Paths.get(TARGET + dir.toString().substring(SOURCES.length()));
if (!Files.exists(targetPath)) {
Files.createDirectory(targetPath);
}
}
return FileVisitResult.CONTINUE;
}
#Override
public FileVisitResult visitFile(Path file, BasicFileAttributes attrs) throws IOException {
Path targetPath = Paths.get(TARGET + file.toString().substring(SOURCES.length()));
copyFile(targetPath, Files.readAllBytes(file));
return FileVisitResult.CONTINUE;
}
}
private static void copyFile (Path path,byte[] bytes){
// write file
try {
Files.write(path, bytes);
} catch (IOException e) {
e.printStackTrace();
}
}
}
Using OKHttpClient to download the file and place in a folder.
Request request = new Request.Builder().url(downloadUrl).build();
Response response;
try {
response = client.newCall(request).execute();
if (response.isSuccessful()) {
fileName = abc.zip
Path targetPath = new File(inDir + File.separator + fileName).toPath();
try (FileOutputStream fos = new FileOutputStream(targetPath)) {
fos.write(response.body().bytes());
}
return 0;
}
} catch (IOException e) {
logger.error(e.getMessage());
}```
In reality its just making a copy of a text.txt file. I know how to use file chooser to choose the file but that is as far as my knowledge really goes.
I can do this:
public BasicFile()
{
JFileChooser choose = new JFileChooser(".");
int status = choose.showOpenDialog(null);
try
{
if (status != JFileChooser.APPROVE_OPTION) throw new IOException();
f = choose.getSelectedFile();
if (!f.exists()) throw new FileNotFoundException();
}
catch(FileNotFoundException e)
{
display(1, e.toString(), "File not found ....");
}
catch(IOException e)
{
display(1, e.toString(), "Approve option was not selected");
}
}
Path object is perfect for copying files,
Try this code to copy a file,
Path source = Paths.get("c:\\blabla.txt");
Path target = Paths.get("c:\\blabla2.txt");
try {
Files.copy(source, target);
} catch (IOException e1) {
e1.printStackTrace();
}
If you have to backup a whole folder, you can use this code
public class BackUpFolder {
public void copy(File sourceLocation, File targetLocation) throws IOException {
if (sourceLocation.isDirectory()) {
copyDirectory(sourceLocation, targetLocation);
} else {
copyFile(sourceLocation, targetLocation);
}
}
private void copyDirectory(File source, File target) throws IOException {
if (!target.exists()) {
target.mkdir();
}
for (String f : source.list()) {
copy(new File(source, f), new File(target, f));
}
}
private void copyFile(File source, File target) throws IOException {
try (
InputStream in = new FileInputStream(source);
OutputStream out = new FileOutputStream(target)) {
byte[] buf = new byte[1024];
int length;
while ((length = in.read(buf)) > 0) {
out.write(buf, 0, length);
}
}
}
public static void main(String[] args) {
try {
BackUpFolder backUpFolder = new BackUpFolder();
String location = "./src/edu/abc/locationFiles/daofile"; //File path you are getting from file chooser
String target = "./src"; //target place you want to patse
File locFile = new File(location);
File tarFile = new File(target);
backUpFolder.copyDirectory(locFile, tarFile);
} catch (IOException ex) {
Logger.getLogger(BackUpFolder.class.getName()).log(Level.SEVERE, null, ex);
}
}
}
Start by taking a look at Basic I/O, which explains the basics of Input/OutputStreams and Readers and Writers, which are used to read/write bytes of data from a source to a destination.
If you're using Java 7 or over, you should also take a look at Copying a File or Directory which is part of newer Files and Paths API, which you can find more information about at File I/O (Featuring NIO.2)
I was wondering whether there is a way to take a given .jar file, selected with a JFileChooser, extract it and put it into a new directory. Then, take all the files from another directory, add it to the directory with the extracted .jar file, and then take all that and package it back up again.
I'm doing this because I want a really easy way to install mods for that game, minecraft, where you can just select your minecraft.jar, and make sure the files for the mod are in a folder, and wait a bit, as indicated by a JProgressBar.
This is all I have so far
import java.io.*;
import java.util.jar.*;
import javax.swing.*;
public class Main extends JFrame {
public Main() {
super("Auto-mod installer");
setSize(300, 60);
setLocationRelativeTo(null);
setResizable(false);
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
JProgressBar bar = new JProgressBar(0, 100);
add(bar);
setVisible(true);
}
public static void main(String[] args) {
Main m = new Main();
}
private void extract(File f) {
//Hrm...
}
private void addModFiles() {
//Uh...
}
private void repackage(File f) {
//What?
}
}
As you can see, I have no idea what I'm doing. I do know what the imports needed are, but that's about it. Help would be appreciated, ranting about anything I did wrong would get me mad. Thanks!
EDIT: If you know a way to get the same results, and it's not the way that I was looking for, please let me know how to do so. As long as I get the results I was looking for, it would be great. Thanks again!
The idea is relatively simple. You have a few gotchas (like what to do if files already exist and that kind of thing), but otherwise...
I'd start by having a look at JarFile
(I'm in the middle of another example, but when I get time, I'll post some stuff)
UPDATE with Example
public class JarTest {
protected static final String OUTPUT_PATH = "..."; // The place you want to extact the jar to
/**
* #param args the command line arguments
*/
public static void main(String[] args) {
new JarTest();
}
public JarTest() {
try {
unjar();
// Copy new contents in...
jar();
} catch (IOException exp) {
exp.printStackTrace();
}
}
// This just recursivly lists through all the files to be included in the new jar
// We don't care about the directories, as we will create them from the file
// references in the Jar ourselves
protected List<File> getFiles(File path) {
List<File> lstFiles = new ArrayList<File>(25);
// If you want the directories, add the "path" to the list now...
File[] files = path.listFiles();
if (files != null && files.length > 0) {
for (File file : files) {
if (file.isDirectory()) {
lstFiles.addAll(getFiles(file));
} else {
lstFiles.add(file);
}
}
}
return lstFiles;
}
// Re-Jar the contents
// You should always attempt to jar back to a new file, as you may not want to effect the original ;)
public void jar() throws IOException {
JarOutputStream jos = null;
try {
String outputPath = OUTPUT_PATH;
// Create a new JarOutputStream to the file you want to create
jos = new JarOutputStream(new FileOutputStream("...")); // Add your file reference
List<File> fileList = getFiles(new File(OUTPUT_PATH));
System.out.println("Jaring " + fileList.size() + " files");
// Okay, I cheat. I make a list of all the paths already added to the Jar only create
// them when I need to. You could use "file.isDirectory", but that would mean you would need
// to ensure that the files were sorted to allow all the directories to be first
// or make sure that the directory reference is added to the start of each recursion list
List<String> lstPaths = new ArrayList<String>(25);
for (File file : fileList) {
// Replace the Windows file seperator
// We only want the path to this element
String path = file.getParent().replace("\\", "/");
// Get the name of the file
String name = file.getName();
// Remove the output path from the start of the path
path = path.substring(outputPath.length());
// Remove the leading slash if it exists
if (path.startsWith("/")) {
path = path.substring(1);
}
// Add the path path reference to the Jar
// A JarEntry is considered to be a directory if it ends with "/"
if (path.length() > 0) {
// At the trailing path seperator
path += "/";
// Check to see if we've already added it out not
if (!lstPaths.contains(path)) {
// At the path entry...we need need this to make it easier to
// extract the files at a later state. There is a way to cheat,
// but I'll let you figure it out
JarEntry entry = new JarEntry(path);
jos.putNextEntry(entry);
jos.closeEntry();
// Make sure we don't try to add the same path entry again
lstPaths.add(path);
}
}
System.out.println("Adding " + path + name);
// Create the actual entry for this file
JarEntry entry = new JarEntry(path + name);
jos.putNextEntry(entry);
// Write the entry to the file
FileInputStream fis = null;
try {
fis = new FileInputStream(file);
byte[] byteBuffer = new byte[1024];
int bytesRead = -1;
while ((bytesRead = fis.read(byteBuffer)) != -1) {
jos.write(byteBuffer, 0, bytesRead);
}
jos.flush();
} finally {
try {
fis.close();
} catch (Exception e) {
}
}
jos.closeEntry();
}
jos.flush();
} finally {
try {
jos.close();
} catch (Exception e) {
}
}
}
public void unjar() throws IOException {
JarFile jarFile = null;
try {
String outputPath = OUTPUT_PATH;
File outputPathFile = new File(outputPath);
// Make the output directories.
// I'll leave it up to you to decide how best to deal with existing content ;)
outputPathFile.mkdirs();
// Create a new JarFile reference
jarFile = new JarFile(new File("C:/hold/Java_Harmony.jar"));
// Get a list of all the entries
Enumeration<JarEntry> entries = jarFile.entries();
while (entries.hasMoreElements()) {
// Get the next entry
JarEntry entry = entries.nextElement();
// Make a file reference
File path = new File(outputPath + File.separator + entry.getName());
if (entry.isDirectory()) {
// Make the directory structure if we can
if (!path.exists() && !path.mkdirs()) {
throw new IOException("Failed to create output path " + path);
}
} else {
System.out.println("Extracting " + path);
// Extract the file from the Jar and write it to disk
InputStream is = null;
OutputStream os = null;
try {
is = jarFile.getInputStream(entry);
os = new FileOutputStream(path);
byte[] byteBuffer = new byte[1024];
int bytesRead = -1;
while ((bytesRead = is.read(byteBuffer)) != -1) {
os.write(byteBuffer, 0, bytesRead);
}
os.flush();
} finally {
try {
os.close();
} catch (Exception e) {
}
try {
is.close();
} catch (Exception e) {
}
}
}
}
} finally {
try {
jarFile.close();
} catch (Exception e) {
}
}
}
}
You can use this very simple library to pack/unpack jar file
JarManager
Very simple
import java.io.File;
import java.io.IOException;
import java.nio.file.Files;
import java.nio.file.Path;
import fr.stevecohen.jarmanager.JarPacker;
import fr.stevecohen.jarmanager.JarUnpacker;
public class MyClass {
public void addFileToJar(String jarPath, String otherFilePath) {
try {
JarUnpacker jarUnpacker = new JarUnpacker();
File myJar = new File("./myfile.jar");
File otherFile = new File(otherFilePath);
Path unpackDir = Files.createTempDirectory(myJar.getName()); //create a temp directory to extract your jar
System.out.println("Unpacking in " + unpackDir.toString());
jarUnpacker.unpack(jarPath, unpackDir.toString()); //extraxt all files contained in the jar in temp directory
Files.copy(otherFile.toPath(), new File(unpackDir.toFile(), otherFile.getName()).toPath()); //copy your file
JarPacker jarRepacker = new JarPacker();
File newJar = new File("./maNewFile.jar");
System.out.println("Packing jar in " + newJar.getAbsolutePath());
jarRepacker.pack(unpackDir.toString(), newJar.getAbsolutePath()); //repack the jar with the new files inside
} catch (IOException e) {
e.printStackTrace();
}
}
}
You can also use maven dependency
<dependency>
<groupId>fr.stevecohen.jarmanager</groupId>
<artifactId>JarManager</artifactId>
<version>0.5.0</version>
</dependency>
You also need my repository
<repository>
<id>repo-reapersoon</id>
<name>ReaperSoon's repo</name>
<url>http://repo-maven.stevecohen.fr</url>
</repository>
Check the last version with the link bellow to use the last dependency
Please use my public issue tracker if you find some bugs
File content[] = new File("C:/FilesToGo/").listFiles();
for (int i = 0; i < content.length; i++){
String destiny = "C:/Kingdoms/"+content[i].getName();
File desc = new File(destiny);
try {
Files.copy(content[i].toPath(), desc.toPath(), StandardCopyOption.REPLACE_EXISTING);
} catch (IOException e) {
e.printStackTrace();
}
}
This is what I have. It copies everything just fine.
But among the contents there are some folders. The folders are copied but the folder's contents are not.
Would recommend using FileUtils in Apache Commons IO:
FileUtils.copyDirectory(new File("C:/FilesToGo/"),
new File("C:/Kingdoms/"));
Copies directories & contents.
Recursion. Here is a method the uses rescursion to delete a system of folders:
public void move(File file, File targetFile) {
if(file.isDirectory() && file.listFiles() != null) {
for(File file2 : file.listFiles()) {
move(file2, new File(targetFile.getPath() + "\\" + file.getName());
}
}
try {
Files.copy(file, targetFile.getPath() + "\\" + file.getName(), StandardCopyOption.REPLACE_EXISTING);
} catch (IOException e) {
e.printStackTrace();
}
}
Didn't test the code, but it should work. Basically, it digs down into the folders, telling it to move the item, if its a folder, go through all its children, and move them, etc.
Just to clarify what needs to be changed in Alex Coleman's answer, for the code to work. Here is the modified version of Alex's code that I tested and that works fine for me:
private void copyDirectoryContents(File source, File destination){
try {
String destinationPathString = destination.getPath() + "\\" + source.getName();
Path destinationPath = Paths.get(destinationPathString);
Files.copy(source.toPath(), destinationPath, StandardCopyOption.REPLACE_EXISTING);
}
catch (UnsupportedOperationException e) {
//UnsupportedOperationException
}
catch (DirectoryNotEmptyException e) {
//DirectoryNotEmptyException
}
catch (IOException e) {
//IOException
}
catch (SecurityException e) {
//SecurityException
}
if(source.isDirectory() && source.listFiles() != null){
for(File file : source.listFiles()) {
copyDirectoryContents(file, new File(destination.getPath() + "\\" + source.getName()));
}
}
}
The question is old by now, but I wanted to share my copy methods using java.nio.file.
Copying source directory: src into a container directory: dst.
"Directory" is just a helper class. In this example you can think of it as "Path" container.
We separate the directory structure from the file content.
It's explicit, and easy to imagine. (Also, it avoids some potential Exceptions thrown by the Files.copy() method if you instead copied all files in "one go")
public static void copy(Directory src, Directory dst, boolean replace) throws IOException {
if (src == null || dst == null) throw new IllegalArgumentException("...");
Path sourcePath = src.path();
Path targetPath = dst.path().resolve(sourcePath.getFileName());
copyStructure(sourcePath,targetPath);
copyContent(sourcePath,targetPath,replace);
}
I.e. we want to copy the folder "top" into the "dst" folder "container".
sourcePath = ...some/location/top
targetPath = ...another/location/container/top
copyStructure: Iterates through the source files. If the source file is a directory and the a target file with equivalent name does not exist, we create
the target folder. (So "copy" is not accurate. We "assure" structure)
private static void copyStructure(final Path source, final Path target) throws IOException {
if (source == null || target == null) throw new IllegalArgumentException("...");
final String tarString = target.toString();
final String srcString = source.toString();
Files.walk(source).forEach(new Consumer<Path>() {
#Override
public void accept(Path srcPath) {
if (Files.isDirectory(srcPath)) {
String subString = srcPath.toString().substring(srcString.length());
Path newFolder = Path.of(tarString,subString);
if (!Files.exists(newFolder)) {
try { Files.createDirectory(newFolder);
} catch (IOException e) {
e.printStackTrace();
}
}
}
}
});
}
Now that we know that a target directory structure exists, we iterate the source files again. But now we only copy the "content" (regular files). Choosing whether to replace existing content. copyContent:
private static void copyContent(final Path source, final Path target, boolean replace) throws IOException {
if (source == null || target == null) throw new IllegalArgumentException("...");
final String tarString = target.toString();
final String srcString = source.toString();
Files.walk(source).forEach(new Consumer<Path>() {
#Override
public void accept(Path srcPath) {
if (Files.isRegularFile(srcPath)) {
String subString = srcPath.toString().substring(srcString.length());
Path newFile = Path.of(tarString,subString);
if (!Files.exists(newFile)) {
try { Files.copy(srcPath,newFile);
} catch (IOException e) {
e.printStackTrace();
}
} else {
if (replace) {
try { Files.copy(srcPath,newFile,
StandardCopyOption.REPLACE_EXISTING);
} catch (IOException e) {
e.printStackTrace();
}
}
}
}
}
});
}