import java.io.BufferedOutputStream;
import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.RandomAccessFile;

/*
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 */

/**
 *
 * @author ram
 */
public class split
{

    public static void main(String[] args) throws Exception
    {
        String fileName = "tifName.tif";
        String fil = "name";
        String type = ".tif";

        File tifFile = new File("C:\\Users\\s\\folder\\car_folder\\" + fileName);
        RandomAccessFile raf = new RandomAccessFile(tifFile, "r");
        long numSplits = 2; //from user input, extract it from args
        long sourceSize = raf.length();
        long bytesPerSplit = sourceSize/numSplits ;
        long remainingBytes = sourceSize % numSplits;

        long maxReadBufferSize = 1 * 1610612736; //1500mb
        for(int destIx = 1; destIx <= numSplits; destIx++) {
            BufferedOutputStream bw = new BufferedOutputStream(new FileOutputStream(fil + "_" + destIx + type));
            if(bytesPerSplit > maxReadBufferSize) {
                long numReads = bytesPerSplit/maxReadBufferSize;
                long numRemainingRead = bytesPerSplit % maxReadBufferSize;
                for(int i=0; i<numReads; i++) {
                    readWrite(raf, bw, maxReadBufferSize);
                }
                if(numRemainingRead > 0) {
                    readWrite(raf, bw, numRemainingRead);
                }
            }
            else {
                readWrite(raf, bw, bytesPerSplit);
            }
            bw.close();
        }
        if(remainingBytes > 0) {
            BufferedOutputStream bw = new BufferedOutputStream(new FileOutputStream("split." + numSplits+1));
            readWrite(raf, bw, remainingBytes);
            bw.close();
        }
            raf.close();
    }

    static void readWrite(RandomAccessFile raf, BufferedOutputStream bw, long numBytes) throws IOException {
        byte[] buf = new byte[(int) numBytes];
        int val = raf.read(buf);
        if(val != -1) {
            bw.write(buf);
        }
    }
}