Here is an example of using the LockableFileWriter class from the Apache Commons IO library in Java to write text to a file while acquiring a lock:

import java.io.File;
import java.io.IOException;
import org.apache.commons.io.output.LockableFileWriter;

public class LockableFileWriterExample {
    public static void main(String[] args) {
        // specify the file to write to
        File file = new File("/path/to/file.txt");
        
        try (LockableFileWriter writer = new LockableFileWriter(file)) {
            // acquire the lock
            writer.lock();
            
            // write text to the file
            writer.write("This is some text to be written to the file.");
            
            // release the lock
            writer.unlock();
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}

In this example, a LockableFileWriter object is created by passing the file to write to as an argument. The LockableFileWriter class extends the FileWriter class, but it adds the ability to acquire and release a lock on the file before and after writing to it.

The lock() method is used to acquire the lock and the unlock() method is used to release the lock.

The write() method is used to write text to the file.

The LockableFileWriter class provides a way to write text to a file while acquiring a lock, this can be useful when working with files that are shared by multiple processes or threads. By acquiring a lock before writing to the file, you can ensure that no other process or thread can write to the file at the same time, preventing data corruption.

The LockableFileWriter class also provides the isLocked() method to check if the file is locked or not, and the getLock() method to get the file lock.