Best way to read a large file containing a single

I did a small experiment for the Reading files having single line string and multiple line strings. The singleLine file is 198890 lengthed and the multiLine file is 208890 lengthed. I tested them with six methods as follows and got the timings and String length that they have read. Here I've mentioned the Test method, Result and the Implementations.

My actual consideration is reading a large file contain single line text in it. According to the results it looks like IO utils is better than others.

So, what is the best way that I can use for this other than the methods that I've implemented below (if any).

Results : (Timings are in seconds. 0 means less than a sec :))

iOTest(). : Single Line Test...
singleStr.txt is deleted!
writeToFile().198890 lenghted String wrote to the file
[ReadWithBufferedReaderByLine] Text length: 198890, Total time: 18
[ReadWithBufferedReaderToCharArray] Text length: 204800, Total time: 8
[ReadWithStreamToByteArray] Text length: 198890, Total time: 8
[ReadWithStreamToByteArrayChunks] Text length: 1950, Total time: 1
[ReadFromApacheFileUtils] Text length: 198890, Total time: 30
[ReadFromApacheIOUtils] Text length: 198890, Total time: 1

iOTest(). : Multi Line Test...
multiStr.txt is deleted!
writeToFile().208890 lenghted String wrote to the file
[ReadWithBufferedReaderByLine] Text length: 198890, Total time: 15
[ReadWithBufferedReaderToCharArray] Text length: 212992, Total time: 2
[ReadWithStreamToByteArray] Text length: 208890, Total time: 1
[ReadWithStreamToByteArrayChunks] Text length: 2040, Total time: 2
[ReadFromApacheFileUtils] Text length: 208890, Total time: 0
[ReadFromApacheIOUtils] Text length: 208890, Total time: 1

Test Method :

public void iOTester(){

        System.out.println("niOTester(). : Single Line Test...");

        String testStr = "";
        for(int i = 0; i < 10000; i++)  testStr += "[Namal"+i+"Fernando] ";

        writeToFile("singleStr.txt", testStr);

        readWithBufferedReaderByLine("singleStr.txt");
        readWithBufferedReaderToCharArray("singleStr.txt");
        readWithStreamToByteArray("singleStr.txt");
        readWithStreamToByteArrayChunks("singleStr.txt");
        readFromApacheFileUtils("singleStr.txt");
        readFromApacheIOUtils("singleStr.txt");

        System.out.println("niOTester(). : Multi Line Test...");

        testStr = "";
        for(int i = 0; i < 10000; i++) testStr += "[Namal"+i+"Fernando] n";

        writeToFile("multiStr.txt", testStr);

        readWithBufferedReaderByLine("multiStr.txt");
        readWithBufferedReaderToCharArray("multiStr.txt");
        readWithStreamToByteArray("multiStr.txt");
        readWithStreamToByteArrayChunks("multiStr.txt");
        readFromApacheFileUtils("multiStr.txt");
        readFromApacheIOUtils("multiStr.txt");


    }

Implementations :

Method 1 : (ReadWithBufferedReaderByLine)

BufferedReader  br          = new BufferedReader(new 

FileReader(file));
String          line        = null;
StringBuilder   sb          = new StringBuilder();

while ((line = br.readLine()) != null) {
    sb.append(line);
}
String          text        = sb.toString();

Method 2 : (ReadWithBufferedReaderToCharArray)

BufferedReader  br              = new BufferedReader(new 

FileReader(file));
StringBuilder   sb          = new StringBuilder();
char[]          chars       = new char[8192];

for(int len; (len = br.read(chars)) > 0;) {
    sb.append(String.valueOf(chars));
}
String          text        = sb.toString();

Method 3 : (ReadWithStreamToByteArray)

InputStream     is          = new FileInputStream(file);
byte[]          b       = new byte[is.available()];
is.read(b);
String          text        = new String(b);

Method 4 : (ReadWithStreamToByteArrayChunks)

InputStream     is          = new FileInputStream(file);
byte[]          b       = new byte[1024];
StringBuilder   sb          = new StringBuilder();

int read;
while((read = is.read(b)) != -1){
    sb.append(String.valueOf(b));
}

String          text        = sb.toString();

Method 5 : (ReadFromApacheFileUtils)

String text  = new String(FileUtils.readFileToByteArray(new File(filePath)));

Method 6: (ReadFromApacheIOUtils)

String text = new String(IOUtils.toByteArray(new FileInputStream(filePath)));

References :

Reading huge line of string from text file

How to read the ByteArray from the file in Java?

---

You can also test this method

String text = new String(Files.readAllBytes(Paths.get(path)));

and also FileChannel with direct buffer

    FileChannel fc = FileChannel.open(path);
    ByteBuffer buf = ByteBuffer.allocateDirect((int)fc.size());
    fc.read(buf);

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