public String findFile()
{
    String line = "";

    try
    {
        File myDir = new File("files");
        File myFile = new File(myDir, "ISBN 123-654.txt");
        BufferedReader br = new BufferedReader(new FileReader(myFile));

        while ((line = br.readLine()) != null)
        {
            System.out.println(line + "1");
        }
    }
    catch (IOException e)
    {
        e.printStackTrace();
    }

    System.out.println(line+"2");
    return line;
}

public String findFile()
    {
        String line = "";
        try {
                File myFile = new File("files", "ISBN 123-654.txt");
               BufferedReader br = new BufferedReader(new FileReader(myFile));

            while ((line = br.readLine()) == null)
                 System.out.println(line + "1");
                br.close();
             }
             catch (IOException e) {
                 e.printStackTrace();
             }

    System.out.println(line+"2");
    return line;
    }

public String findFile(){
    String fileContent = "";

    try {
        File myDir = new File("files");
        File myFile = new File(myDir, "ISBN 123-654.txt");
        BufferedReader br = new BufferedReader(new FileReader(myFile));

        String line;
        while ((line = br.readLine()) != null){
            System.out.println(line + "1");
            fileContent += line;
        }
       }
        catch (IOException e){
        e.printStackTrace();
    }
    System.out.println(fileContent+"2");
    return fileContent;
}

public String findFile()
{
    String line = "";
    String rtLine = null;

    try
    {
        File myDir = new File("files");
        File myFile = new File(myDir, "ISBN 123-654.txt");
        BufferedReader br = new BufferedReader(new FileReader(myFile));

        while ((line = br.readLine()) != null)
        {
            rtLine = line;
            System.out.println(line + "1");
        }
    }
    catch (IOException e)
    {
        e.printStackTrace();
    }

    System.out.println(line+"2");
    return rtLine;
}

try {
List<String> lines = Files.readLines(new File(PATH_TO_FILE), Charsets.UTF_8);
//return content lines separated by comma
return Joiner.on(",").join(lines);

} catch (IOException e) {
e.printStackTrace();
}

try {
List<String> lines = Files.readLines(new File(PATH_TO_FILE), Charsets.UTF_8);
//return last line
if (lines.size() > 0) {
    return lines.get(lines.size() - 1);
} else {
    return null;
}

} catch (IOException e) {
e.printStackTrace();
}

File myFile = new File("files", "ISBN 123-654.txt");