Convert the file content to a byte array and return

How to convert the file content into a byte array and return it? For this problem, I offer my first successful code~

package com.succez.task1;

import java.io.ByteArrayOutputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.IOException;

/**
 * <p>Copyright: Copyright (c) 2018</p>
 * <p>succez</p>
 * @author ZhangJinjin
 * @createdate May 3, 2018
 */
public class fileToBuf {

    /** 
     * Convert the file content into a byte array and return, if the file does not exist or the read error returns null 
     *
     * Here you need to create a byte array buffer in memory, and write the read file byte data into the buffer
     * Finally convert the byte stream into a byte array and close the resource
     * Need to catch when file not found exception and input and output exception occur
     */
    public static byte[] file2buf(File fobj){
        byte[] buffer = null;
        try{
            if (!fobj.exists())
            {
                return null;
            }
            
            FileInputStream fis = new FileInputStream(fobj);
            ByteArrayOutputStream bos = new ByteArrayOutputStream();
            byte[] b = new byte[1024];
            int len=-1;
            while ((len = fis.read(b)) != -1)
            {
                bos.write(b, 0, len);
            }
            fis.close();
            bos.close();
            buffer = bos.toByteArray();
        }
        catch (FileNotFoundException e)
        {
            e.printStackTrace ();
        }
        catch (IOException e)
        {
            e.printStackTrace ();
        }
        return buffer;
    }
    
    /*
     * Two test cases
     * */
    public static void main(String []args){
        File fobj1 = new File("E:\\TestExample\\test1.txt");
        byte[] buffer1=fileToBuf.file2buf(fobj1);
        System.out.println(buffer1);
        File fobj2 = new File("E:\\TestExample\\test2.docx");
        byte[] buffer2=fileToBuf.file2buf(fobj2);
        System.out.println(buffer2);
    }
}

 The result is as follows:

After careful analysis, I think it's pretty good, how can I change it, just kidding!

---

The process goes through again:

FileInputStream  gets input bytes from a file in the filesystem, reading a stream of textual raw bytes.

ByteArrayOutputStream This class implements an output stream in which data is written to a byte array. The buffer grows automatically as data is written. Data can be obtained using toByteArray()and toString().

Keep reading data and writing it to the buffer

Convert to byte array using toByteArray() method.

      

So, no problem~