In this tutorial, we will show you three Java examples to construct a file path :
- File.separator or System.getProperty(“file.separator”) (Recommended)
- File file = new File(workingDir, filename); (Recommended)
- Create the file separator manually. (Not recommend, just for fun)
1. File.separator
Classic Java example to construct a file path, using File.separator or System.getProperty("file.separator"). Both will check the OS and returns the file separator correctly, for example,
- Windows =
\ - *nix or Mac =
/
FilePathExample1.java
package com.mkyong.file;
import java.io.File;
import java.io.IOException;
public class FilePathExample1 {
public static void main(String[] args) {
try {
String filename = "newFile.txt";
String workingDirectory = System.getProperty("user.dir");
//****************//
String absoluteFilePath = "";
//absoluteFilePath = workingDirectory + System.getProperty("file.separator") + filename;
absoluteFilePath = workingDirectory + File.separator + filename;
System.out.println("Final filepath : " + absoluteFilePath);
//****************//
File file = new File(absoluteFilePath);
if (file.createNewFile()) {
System.out.println("File is created!");
} else {
System.out.println("File is already existed!");
}
} catch (IOException e) {
e.printStackTrace();
}
}
}
Output
Final filepath : /Users/mkyong/Documents/workspace/maven/fileUtils/newFile.txt
File is created!
2. new File()
Some developers are using new File() API to construct the file path.
FilePathExample2.java
package com.mkyong.file;
import java.io.File;
import java.io.IOException;
public class FilePathExample2 {
public static void main(String[] args) {
try {
String filename = "newFile.txt";
String workingDirectory = System.getProperty("user.dir");
//****************//
File file = new File(workingDirectory, filename);
//****************//
System.out.println("Final filepath : " + file.getAbsolutePath());
if (file.createNewFile()) {
System.out.println("File is created!");
} else {
System.out.println("File is already existed!");
}
} catch (IOException e) {
e.printStackTrace();
}
}
}
Output
Final filepath : /Users/mkyong/Documents/workspace/maven/fileUtils/newFile.txt
File is created!
3. Manual file separator
Check the system OS and create file path manually, just for fun, not recommend.
FilePathExample3.java
package com.mkyong.file;
import java.io.File;
import java.io.IOException;
public class FilePathExample3 {
public static void main(String[] args) {
try {
String filename = "testing.txt";
String workingDir = System.getProperty("user.dir");
String absoluteFilePath = "";
//****************//
String your_os = System.getProperty("os.name").toLowerCase();
if (your_os.indexOf("win") >= 0) {
//if windows
absoluteFilePath = workingDir + "\\" + filename;
} else if (your_os.indexOf("nix") >= 0 ||
your_os.indexOf("nux") >= 0 ||
your_os.indexOf("mac") >= 0) {
//if unix or mac
absoluteFilePath = workingDir + "/" + filename;
}else{
//unknow os?
absoluteFilePath = workingDir + "/" + filename;
}
System.out.println("Final filepath : " + absoluteFilePath);
//****************//
File file = new File(absoluteFilePath);
if (file.createNewFile()) {
System.out.println("Done");
} else {
System.out.println("File already exists!");
}
} catch (IOException e) {
e.printStackTrace();
}
}
}
Output
Final filepath : /Users/mkyong/Documents/workspace/maven/fileUtils/newFile.txt
File is created!
String workingDirectory = System.getProperty(“user.dir”);
String absoluteFilePath = workingDirectory + File.separator ;
System.out.println(absoluteFilePath);
— Construct file path in 2 lines.. awesome.. thanks
Just apply that: System.getProperty(“file.separator”) and forget the rest and this particular tutorial which is not relevant at all.
Thanks for your input, article is updated with more ways to construct a file path.
perfect way
Or
System.getProperty(“file.separator”)
Nice Work!
your tutorial is good…but require more description..
Easy and better examples.it is used improve my programming knowledge..thank u
This can be even more simple 🙂
String filename = “testing.txt”;
String workingDir = System.getProperty(“user.dir”);
File file = new File(workingDir, filename);
hi kdt, thanks for your tip ~