在Java中读取32位二进制数

Question

I am trying to read five 32-bit binary numbers and print them as int. Here is my code:

FileInputStream fin = new FileInputStream(file);
        int count = 5;

        for (int i = 0; i < count; i++) {
            byte[] input = file.getBytes();
            String bin=Integer.toBinaryString(0xFF & input[i] | 0x100).substring(1);
            System.out.println(bin);

I am getting this:

01010011
01101110
00110011
01011111
01010010

What am I doing wrong? thanks

Answer 1

You're not actually reading from the file, but printing the binary representation of the first five characters of the name of the file. Use fin.read() to read bytes from the file.

You can also use DataInputStream to read 32 bit big endian integers directly, instead of reading them as 4 individual bytes.

Answer 2

If you need to read five big-endian 32-bit integers, then I suggest that you use DataInputStream , eg

final int count = 5;

try (DataInputStream dis = new DataInputStream(new FileInputStream(file))) {
    for (int i = 0; i < count; i++) {
        int value = dis.readInt();
        System.out.println(Integer.toBinaryString(value));
    }
}