I have a problem with that code:
public class Files {
public static void main(String[] args) throws IOException {
// filter files AAA.txt and BBB.txt from another's
File f = new File("d:\\dir"); // current directory
File f1 = new File("d:\\dir1\\");
FilenameFilter textFilter = new FilenameFilter() {
public boolean accept(File dir, String name) {
if (name.startsWith("A") && name.endsWith(".TXT")) {
//System.out.println(name);
return true;
}
else if (name.startsWith("B") && name.endsWith(".TXT")) {
//System.out.println(name);
return true;
}
else {
//System.out.println(name);
return false;
}
}
};
File[] files = f.listFiles(textFilter);
for (File file : files) {
if (file.getName().startsWith("A") ) {
//here save file to d:\\folder1\\
}
}
}
}
How can I save files with specific name in example AAA.txt to folder1 and BBB.txt to folder 2. Thanks for any examples
From Files class from Java 7:
Use move(Path source, Path target, CopyOption... options)
import static java.nio.file.StandardCopyOption.*;
import java.nio.file.FileSystem;
import java.nio.file.Path;
import java.nio.file.Files;
...
for (File file : files) {
if (file.getName().startsWith("A") ) {
//here save file to d:\\folder1\\
// convert file to Path object use toPath() method.
Path targetFilePath = FileSystems.getDefault().getPath("d:\\folder1\\").resolve(file.getFileName())
Files.move(file.toPath(), targetFilePath , REPLACE_EXISTING);
}
}
Related
I have a problem, i have this directory with 1k+ files and some folders. I need find the path of the files(which are in subdirectories) that starts with "BCM", but not only the first i find but every single file which start with that.
I tried looking at other answers about this topic but i couldn't find help,
tried using this code:
File dir = new File("K:\\Jgencs");
FilenameFilter filter = new FilenameFilter()
{
public boolean accept (File dir, String name)
{
return name.startsWith("BCM");
}
};
String[] children = dir.list(filter);
if (children == null)
{
System.out.println("No directory found");
}
else
{
for (int i = 0; i< children.length; i++)
{
String filename = children[i];
System.out.println(filename);
File h = new File(dir,filename);
System.out.println(h.getAbsolutePath()
[UPDATED] This is how you can achieve using plain Java and filter text from a variable passing as parameter:
Here is my directory: /tmp
And here is the code running:
import java.io.File;
import java.io.FileFilter;
import java.io.IOException;
import java.util.ArrayList;
import java.util.List;
public class GetAllFilesInDirectory {
public static void main(String[] args) throws IOException {
String filter = "BCM";
List<File> files = listFiles("/tmp", new CustomerFileFilter(filter));
for (File file : files) {
System.out.println("file: " + file.getCanonicalPath());
}
}
private static List<File> listFiles(String directoryName, CustomerFileFilter fileFilter) {
File directory = new File(directoryName);
List<File> files = new ArrayList<>();
// Get all files from a directory.
File[] fList = directory.listFiles(fileFilter);
if(fList != null) {
for (File file : fList) {
if (file.isFile()) {
files.add(file);
} else if (file.isDirectory()) {
files.addAll(listFiles(file.getAbsolutePath(), fileFilter));
}
}
}
return files;
}
}
class CustomerFileFilter implements FileFilter {
private final String filterStartingWith;
public CustomerFileFilter(String filterStartingWith) {
this.filterStartingWith = filterStartingWith;
}
#Override
public boolean accept(File file) {
return file.isDirectory() || file.isFile() && file.getName().startsWith(filterStartingWith);
}
}
This is the output:
file: /private/tmp/BCM01.txt
file: /private/tmp/BCM01
file: /private/tmp/subfolder1/BCM02.txt
Doing recursive calls to the method when finding a directory to also list the files form inside, and filtering by name the files before adding.
You want Files.walk:
try (Stream<Path> files = Files.walk(Paths.get("K:\\Jgencs"))) {
files.filter(f -> f.getFileName().toString().startsWith("BCM")).forEach(
file -> System.out.println(file));
}
Description : I am trying to parse my main directory to find all the files of type ".jpg" and my code is able to return all the files that are needed. example "C:\Ravi\Sources", in this directory i have mixed files of .xml, .jpg, .gif, now i am also having sub folders inside this directory but i don't know
how to modify my code to check for sub-directories as well.
Expertise help is required here :
Code Snippet :
enter code here
import java.io.File;
import java.io.FilenameFilter;
import java.io.IOException;
import java.awt.image.BufferedImage;
import javax.imageio.ImageIO;
import java.io.PrintStream;
public class Subdirectory {
static File f = new File("C:\\Users\\kasharma\\Desktop\\Travelocity R8.3_8.3.0.apk\\res");// File f will represent the folder....
static String[] extensions = new String[]{"png", "jpg", "gif" }; // Declaring array of supported filters...
// Applying filter to identify images based on their extensions...
static FilenameFilter Image_Filter = new FilenameFilter() {
public boolean accept(File f, String name)
{
for(String ext: extensions){
if(name.endsWith("."+ ext)){
return(true);
}
}
return(false);
}
};
public static void goThroughDirectories(String path)
{
}
public static void main(String[] args) {
String path = "C:\\Users\\kasharma\\Desktop\\Travelocity R8.3_8.3.0.apk\\res";
for (File file : f.listFiles(Image_Filter))
{
if (f.isDirectory()) goThroughDirectories(path+f.getName());
BufferedImage img = null;
try {
img = ImageIO.read(file);
System.out.println("image "+ file.getName());
} catch (IOException e) {
// handle errors here
}
}
}
}
Look at java.nio.files, especially the walkFileTree(...) and find(...) methods. Java 8 includes a builtin capability for this.
Using walkFileTree:
public static void main(String[] args) throws Exception
{
Path p = Paths.get("D:/");
Files.walkFileTree(p,
new SimpleFileVisitor<Path>() {
#Override
public FileVisitResult visitFile(Path file, BasicFileAttributes attrs) throws IOException
{
System.out.println(file.toFile().getName());
return FileVisitResult.CONTINUE;
}
}
);
}
Here's an even better solution using find that returns a lazily populated stream and filters for .jpg at the same time:
public static void main(String[] args) throws Exception
{
Path p = Paths.get("D:/");
Files
.find(
p,
Integer.MAX_VALUE,
(path,attr) -> path.toString().endsWith(".jpg"))
.forEach(path -> System.out.println(path.toFile().getName()));
}
This will give you the idea. This is pseudocode.
void goThroughDirectories(String path)
{
for(File f : fileList)
{
if(f.isDirectory()) goThroughDirectories(path+f.getName());
else {
//do something
}
}
}
I would like to search for files recursively. According to other solutions, I have already done a big portion of the code:
public static File[] getFiles(String path) {
File file = new File(path);
// Get the subdirectories.
String[] directories = file.list(new FilenameFilter() {
#Override
public boolean accept(File current, String name) {
return new File(current, name).isDirectory();
}
});
for (String dir : directories) {
// Doing recursion
}
// Get the files inside the directory.
FileFilter fileFilter = new FileFilter();
File[] files = file.listFiles(fileFilter);
return files;
}
FileFilter is just a custom filter of mine. My problem is that I don't know how to do the recursion in this case. Of course I could call getFiles() again for each subdirectory with the subdirectory path as argument but somehow the returning File array must be merged.
Does somebody have a solution?
Use the find() method.
/* Your filter can be initialized however you need... */
YourCustomFilter filter = new YourCustomFilter(extension, maxSize);
try (Stream<Path> s = Files.find(dir, Integer.MAX_VALUE, filter::test)) {
return s.map(Path::toFile).toArray(File[]::new);
}
This assumes your custom filter has a method called test() that accepts the file and its attributes; you'll need to rework your current file filter a bit to accommodate this.
boolean test(Path path, BasicFileAttributes attrs) {
...
}
Working example: http://screencast.com/t/buiyV9UiEa
You can try something like this:
//add this imports
import java.io.File;
import java.io.FilenameFilter;
import java.util.List;
import java.util.ArrayList;
import java.util.Arrays;
public static File[] getFiles(String path) {
File file = new File(path);
// Get the subdirectories.
String[] directories = file.list(new FilenameFilter() {
#Override
public boolean accept(File current, String name) {
return new File(current, name).isDirectory();
}
});
//Use a list to save the files returned from the recursive call
List<File> filesList = new ArrayList<File>();
if( directories != null){
for (String dir : directories) {
// Doing recursion
filesList.addAll( Arrays.asList(getFiles(path + File.separator + dir)) );
}
}
// Get the files inside the directory.
FileFilter fileFilter = new FileFilter();
File[] files = file.listFiles(fileFilter);
//Merge the rest of the files with the files
//in the current dir
if( files != null)
filesList.addAll( Arrays.asList(files) );
return filesList.toArray(new File[filesList.size()]);
}
Code tested and working. Hope this helps.
import java.util.Arrays;
import java.util.ArrayList;
Put a fail-safe right after you initialize file (in case of a bad path on the first call).
if (!file.isDirectory()) return new File[0];
And change the last part of your code to:
FileFilter fileFilter = new FileFilter();
ArrayList<File> files = new ArrayList(Arrays.asList(file.listFiles(fileFilter)));
for (String dir : directories) {
files.addAll(Arrays.asList(getFiles(dir)));
}
return files.toArray(new File[0]);
(the toArray method expands the array that you pass to it if it's too small) Ref
You should do something like this:
import java.io.File;
import java.util.ArrayList;
import java.util.Arrays;
public static File[] getFiles(String path) {
File file = new File(path);
String[] directories = file.list(new FilenameFilter() {
#Override
public boolean accept(File current, String name) {
return new File(current, name).isDirectory();
}
});
ArrayList<File> files = Arrays.asList(file.listFiles(new FileFilter()));
for (String dir : directories) {
files.addAll(getFiles(dir));
}
return files.toArray(new File[list.size()]);
}
The new File[list.size()] is required because otherwise file.toArray() would return Object[].
Also, you should use a lambda expression instead of FilenameFilter, like so:
String[] directories = file.list((File current, String name) -> {
return new File(current, name).isDirectory();
});
Task :
Write a Java application that accepts two file names as arguments: dirName and fileName Find all non-directory files contained in directory dirName whose name ends in ".java"
I tried to use this code but how can I print out the files ending with ".java" ?
It's the first time I work with this things and I don't know how to use them.
import java.io.File;
import java.io.FilenameFilter;
public class Filter {
public static File[] finder(String dirName){
File dir = new File(dirName);
return dir.listFiles(new FilenameFilter() {
public boolean accept(File dir, String filename)
{ return filename.endsWith(".txt"); }
});
}
public static void main(String[] args){
String dirName = "src";
System.out.println(finder(dirName));
}
}
return !dir.isDirectory() && filename.endsWith(".java");
Thanks for the help. It works fine now .
import java.io.*;
public class Filter {
public static File[] finder(String dirName) {
File dir = new File(dirName);
return dir.listFiles(new FilenameFilter() {
public boolean accept(File dir, String filename) {
return filename.endsWith(".java");
}
});
}
public static void main(String[] args) {
String dirName = "src";
File[] files = finder(dirName);
for (File i: files)
System.out.println(i.getName());
}
}
I want to make my program print huge list of all files that I have on my computer. My problem is that it only prints files from first folder of the first hard-drive, when I want it to print all files located on my computer. Any ideas what am I doing wrong here? Thanks.
Here is code I use:
Main:
import java.io.File;
import java.util.ArrayList;
import java.util.Arrays;
public class Main {
public static void main(String[] args) {
ArrayList<File> roots = new ArrayList();
roots.addAll(Arrays.asList(File.listRoots()));
for (File file : roots) {
new Searcher(file.toString().replace('\\', '/')).search();
}
}
}
and Searcher class:
import java.io.File;
public class Searcher {
private String root;
public Searcher(String root) {
this.root = root;
}
public void search() {
System.out.println(root);
File folder = new File(root);
File[] listOfFiles = folder.listFiles();
for (File file : listOfFiles) {
String path = file.getPath().replace('\\', '/');
System.out.println(path);
if (!path.contains(".")) {
new Searcher(path + "/").search();
}
}
}
}
I just tried this and it worked for me. I did have to add one null check and changed the directory evaluation method though:
package test;
import java.io.File;
import java.util.ArrayList;
import java.util.Arrays;
public class Searcher {
public static void main(String[] args) {
ArrayList<File> roots = new ArrayList<File>();
roots.addAll(Arrays.asList(File.listRoots()));
for (File file : roots) {
new Searcher(file.toString().replace('\\', '/')).search();
}
}
private String root;
public Searcher(String root) {
this.root = root;
}
public void search() {
System.out.println(root);
File folder = new File(root);
File[] listOfFiles = folder.listFiles();
if(listOfFiles == null) return; // Added condition check
for (File file : listOfFiles) {
String path = file.getPath().replace('\\', '/');
System.out.println(path);
if (file.isDirectory()) {
new Searcher(path + "/").search();
}
}
}
}
You should update your search method like this:
public void search() {
System.out.println(root);
File folder = new File(root);
File[] listOfFiles = folder.listFiles();
for (File file : listOfFiles) {
String path = file.getPath().replace('\\', '/');
System.out.println(path);
if (file.isDirectory()) {
new Searcher(path + "/").search();
}
}
}
If Java 7 is an option, look into the walkFileTree() method. It will allow you to visit all files and directories in a tree, which you can start from the root of your drive. Just implement a basic FileVisitor to process the file attributes for each Path. You can get started here.
If you're using Java SE 7, use the new file API:
http://docs.oracle.com/javase/7/docs/api/java/nio/file/FileVisitor.html
http://docs.oracle.com/javase/7/docs/api/java/nio/file/Files.html#walkFileTree%28java.nio.file.Path,%20java.util.Set,%20int,%20java.nio.file.FileVisitor%29
http://docs.oracle.com/javase/7/docs/api/java/nio/file/Files.html#walkFileTree%28java.nio.file.Path,%20java.nio.file.FileVisitor%29
I don't know what error you are getting but I got a NPE because you are not checking for the null after the following line.
File[] listOfFiles = folder.listFiles();
After changing the code as follows it seemed to run fine , I stopped it because I have a lot of files. I am assuming it will go on to the next root after the first root(c:/ in my case)
import java.io.File;
import java.util.ArrayList;
import java.util.Arrays;
public class Search {
public static void main(String[] args) {
ArrayList<File> roots = new ArrayList();
roots.addAll(Arrays.asList(File.listRoots()));
for (File file : roots) {
System.out.println(file.toString());
new Searcher(file.toString().replace('\\', '/')).search();
}
}
}
class Searcher {
private String root;
public Searcher(String root) {
this.root = root;
}
public void search() {
System.out.println(root);
File folder = new File(root);
File[] listOfFiles = folder.listFiles();
if(listOfFiles!=null)
{
for (File file : listOfFiles) {
String path = file.getPath().replace('\\', '/');
System.out.println(path);
if (!path.contains(".")) {
new Searcher(path + "/").search();
}
}
}
}
}