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import static java.lang.Math.ceil;
import static java.lang.Math.min;
import static java.lang.Math.sqrt;
import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.nio.ByteBuffer;
import java.nio.LongBuffer;
import java.nio.channels.FileChannel;
public class MainClass {
public static void main(String[] args) {
int count = 100;
long[] numbers = new long[count];
for (int i = 0; i < numbers.length; i++) {
numbers[i] = i;
}
File aFile = new File("data.bin");
FileOutputStream outputFile = null;
try {
outputFile = new FileOutputStream(aFile);
} catch (FileNotFoundException e) {
e.printStackTrace(System.err);
System.exit(1);
}
FileChannel file = outputFile.getChannel();
final int BUFFERSIZE = 100;
ByteBuffer buf = ByteBuffer.allocate(BUFFERSIZE);
LongBuffer longBuf = buf.asLongBuffer();
int numberWritten = 0;
while (numberWritten < numbers.length) {
longBuf.put(numbers, numberWritten, min(longBuf.capacity(), numbers.length - numberWritten));
buf.limit(8 * longBuf.position());
try {
file.write(buf);
numberWritten += longBuf.position();
} catch (IOException e) {
e.printStackTrace(System.err);
System.exit(1);
}
longBuf.clear();
buf.clear();
}
try {
System.out.println("File written is " + file.size() + " bytes.");
outputFile.close();
} catch (IOException e) {
e.printStackTrace(System.err);
System.exit(1);
}
}
}
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