In Java 7 or higher, you can use Java NIO API's Path.toAbsolutePath() method to get the absolute path of a file:

Path path = Paths.get("input.txt");

// get absolute path
String filePath = path.toAbsolutePath().toString();

// print absolute path
System.out.println(filePath);

Alternatively, you can also call getAbsolutePath() on a File object to get the file's complete path as shown below:

File file = new File("input.txt");

// get absolute path
String filePath = file.getAbsolutePath();

// print absolute path
System.out.println(filePath);

Further Reading

You may be interested in other Java I/O articles:

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