how to delete the content of text file without deleting itself

Question

I want to copy the content of file \'A\' to file \'B\'. after the copying is done I want to clear the content of file \'A\' and want to write on it from its beginning. I can

Answer 1

using : New Java 7 NIO library, try

        if(!Files.exists(filePath.getParent())) {
            Files.createDirectory(filePath.getParent());
        }
        if(!Files.exists(filePath)) {
            Files.createFile(filePath);
        }
        // Empty the file content
        writer = Files.newBufferedWriter(filePath);
        writer.write("");
        writer.flush();

The above code checks if Directoty exist if not creates the directory, checks if file exists is yes it writes empty string and flushes the buffer, in the end yo get the writer pointing to empty file