file managing - text file managing java - java

I've been trying to create files inside some directories but haven't been able to figure it out.
The point is to create text files inside package dir: com.resources.files but my idea doesn't work.
public boolean archiveFile() {
//
InputStream str = this.getClass().getResourceAsStream("/com/resources/files/"+Filename.txt
boolean bol = false;
file = new File( str.toString() );
if(!file.exists()) {
try {
file.createNewFile();
bol = true;
} catch (Exception e) {
e.printStackTrace();
}// try-catch
}else {
bol = false;
} // if - else
return bol;
}// archiveFile

Resources are not files, and resource paths are not directories. Consider the case where a WAR file is being executed without unzipping.
You can't do this.

Related

Trouble copying file in Android

My problem is not How to make a copy of a File in Android, My problem is why it fails to make a copy.
After my app downloads a file am trying to copy it to another folder (The end user can save the file in several folder, that why i download once and copy to the rest). I do have the origin file path like:
/storage/emulated/0/MyAppFolder/FolderCreatedByUser1/theFile.pdf
And am trying to copy it to
/storage/emulated/0/MyAppFolder/FolderCreatedByUser2/
With this code (Code improved by Robert Nekic):
public static boolean copyFile(File src, File[] dst) {
boolean result = true;
if (src.exists()) {
String srcName = src.getName();
for (File file : dst) {
String to = file.getPath();
try {
File destination = new File(to, srcName);
if (destination.createNewFile()) {
FileChannel srcChnl = new FileInputStream(src).getChannel();
FileChannel dstChnl = new FileOutputStream(destination).getChannel();
dstChnl.transferFrom(srcChnl, 0, srcChnl.size());
srcChnl.close();
dstChnl.close();
} else {
result = false;
System.out.println("Unable to create destination " + destination.getPath());
}
} catch (Exception e) {
result = false;
System.out.println(e.getMessage());
break;
}
}
} else {
result = false;
System.out.println("File " + src.getPath() + " doesn't exist.");
}
return result;
}
The file exist, but am keep getting errors when copying it to the destiny file like:
/storage/emulated/0/MyAppFolder/FolderCreatedByUser2/theFile.pdf: open failed: ENOENT (No such file or directory)
It fails in both streams, when trying to open the src file and/or destination file:
FileChannel srcChnl = new FileInputStream(src).getChannel();
FileChannel dstChnl = new FileOutputStream(destination).getChannel();
Permission to write are granted. The destination folders are created previously to the download of the file, the user can't select a destination if the directory isn't created.
destination = new File(to, srcName); creates a new File instance but does not create the underlying file. You can verify by checking destination.exists(). I believe all you need is:
destination = new File(to, srcName);
destination.createNewFile();
Also, your src path string manipulation and stuff in the first half of your code seems unnecessary and might be introducing an error that could be resolved with something more concise:
public static boolean copyFile(File src, File[] dst) {
boolean result = true;
if (src.exists()) {
String srcName = src.getName();
for (File file : dst) {
String to = file.getPath();
try {
File destination = new File(to, srcName);
if (destination.createNewFile()) {
FileChannel srcChnl = new FileInputStream(src).getChannel();
FileChannel dstChnl = new FileOutputStream(destination).getChannel();
dstChnl.transferFrom(srcChnl, 0, srcChnl.size());
srcChnl.close();
dstChnl.close();
} else {
result = false;
System.out.println("Unable to create destination " + destination.getPath());
}
} catch (Exception e) {
result = false;
System.out.println(e.getMessage());
break;
}
}
} else {
result = false;
System.out.println("File " + src.getPath() + " doesn't exist.");
}
return result;
}

how to create dynamic paths in java and write the file data in java

I will get dynamic paths from database. Example: 1.xyz/abc/file1.txt
2.pqr/file2.txt
Now I need to append these paths to existing file (eg:/users/rama/) and save that file
my final directory should like /users/rama/xyz/abc/file1.txt
I am able to create directories such as xyz/abc if they don't exist, but the problem is file1.txt is also created as directory instead of file.
I am able to create directories such as xyz/abc if they don't exist,
but the problem is file1.txt is also created as directory instead of
file.
Because you are creating the directories until *.txt. Below an example of code to acheive what you want:
String prefix = "/users/rama/";
String filePath = "xyz/abc/file1.txt";
// concatenation => /users/rama/xyz/abc/file1.txt
String fullPath = prefix.concat(filePath);
PrintWriter writer;
try {
// Getting the directory path : /users/rama/xyz/abc/
int lastIndexOfSlash = fullPath.lastIndexOf("/");
String path = filePath.substring(0, lastIndexOfSlash);
File file = new File(path);
// If /users/rama/xyz/abc/ don't exist then creating it.
if(!file.exists()) {
file.mkdirs();
}
// Creating the file.
writer = new PrintWriter(fullPath, "UTF-8");
writer.println("content");
writer.close();
} catch (FileNotFoundException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (UnsupportedEncodingException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}

How to check file is opened or not in java is not working

I try to check file is opened or not in java using following examples . I use Apache Commons IO library...
boolean isFileUnlocked = false;
try {
org.apache.commons.io.FileUtils.touch(yourFile);
isFileUnlocked = true;
} catch (IOException e) {
isFileUnlocked = false;
}
if(isFileUnlocked){
// Do stuff you need to do with a file that is NOT locked.
} else {
// Do stuff you need to do with a file that IS locked
}
This brings me a wrong formation . When I am not opened the exact file, this show me the file has opened. If file is not opened, result is false and this cannot be possible .
Other example is here,
public boolean isFileOpened(File file){
boolean res = false;
FileChannel channel = new RandomAccessFile(file, "rw").getChannel();
// Get an exclusive lock on the whole file
FileLock lock = channel.lock();
try {
//The file is not already opened
lock = channel.tryLock();
} catch (OverlappingFileLockException e) {
// File is open by someone else
res = true;
} finally {
lock.release();
}
return res;
}
This also brings me incorrect information.
I get these examples from here Java: Check if file is already open
Now my problem is how could I check file is opened or not in java correctly ?
Thank you.

Unable to located generated file

I am generating a file using the following syntax
File file = new File("input.txt");
The problem is that it is saying that it is writing to the file but I am not able to locate where the file is created, I searched my entire workspace. The expectation was that it would be created in the same folder as my code which is executing.
Any ideas?
Rest of the code :
File file = new File("input.txt");
// if file doesnt exists, then create it
if (!file.exists()) {
try {
file.createNewFile();
} catch (IOException e) {
e.printStackTrace();
}
}
You could do a sop on the absolute path and you would get the path:
File file = new File("input.txt");
System.out.println("" + file.getAbsolutePath());
if (!file.exists()) {
try {
file.createNewFile();
} catch (IOException e) {
e.printStackTrace();
}
}
When you create file through relative paths, Java uses System.getProperty("user.dir"). So, in your case the full path to file will be System.out.println(System.getProperty("user.dir") + "/input.txt");.

Recursing through a directory in java, I want to skip a step on the top level

I am trying to output a list of files within a directory recursively (not including the name of the name of the directory that I am starting with (just the contents of it and all files recursing down the tree after that)
here is what I have at the minute. It Might have errors here and there, but the idea is that it will print all the names of every file in the tree recursively. My problem is that I don't want it to print the name of the directory in which they live.
I think my problem is that I am using System.out.println at the start of the recursive method, which means it gets used every time. Which is desirable behavior for every directory BELOW the first one. Its an annoying little problem that I could use some help on. Thanks in advance.
public static void listFiles(String path)
{
File basedir = new File(path);
System.out.println(path.getName());
try
{
File[] files = basedir.listFiles();
for (File file : files)
{
// If Dealing with a directory, call recursively to the function
if (file.isDirectory())
{
listFiles(file.getPath());
}
else
{
System.out.println(file.getName());
}
}
}
catch(IOException ex)
{
System.out.println(ex);
}
}
public static void listFiles(String path, boolean firstCall)
{
File basedir = new File(path);
if(!firstCall)
{
System.out.println(path.getName());
}
try
{
File[] files = basedir.listFiles();
for (File file : files)
{
// If Dealing with a directory, call recursively to the function
if (file.isDirectory())
{
listFiles(file.getPath(), false); //false here because it is not the first call
}
else
{
System.out.println(file.getName());
}
}
}
catch(IOException ex)
{
System.out.println(ex);
}
}
Add a boolean parameter that specifies if it is the first call. When you call the method pass true to the parameter. Also path.getName() is not valid String doesn't have a function getName() maybe you meant basedir.getName()...also remove try catch block IOException can't occur there.

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