Question

The java project i am working on requires me to write the java equivalent of this C code:

void read_hex_char(char *filename, unsigned char *image)
{
    int     i;
    FILE   *ff;
    short  tmp_short;
    ff = fopen(filename, "r");
    for (i = 0; i < 100; i++)
    {
        fscanf(ff, "%hx", &tmp_short);
        image[i] = tmp_short;
    }
    fclose(ff);
}

I have written this Java code.

void read_hex_char(String filename, char[] image) throws IOException
{
    Scanner s=new Scanner(new BufferedReader(new FileReader(filename)));
    for(int i=0;i<100;i++)
    {
        image[i]=s.nextShort();
    }
    s.close();
 }

Is this code correct? If its not, what corrections should be done?

Answer 1

I would go with a FileInputStream and read byte to byte (a short is just two bytes, char is more “complex” than just a short http://docs.oracle.com/javase/tutorial/java/nutsandbolts/datatypes.html). Simple byte extraction code from my project :

public static byte[] readFile(File file) throws IOException {
    FileInputStream in = new FileInputStream(file);
    ByteArrayOutputStream bos = new ByteArrayOutputStream();
    int ch = -1;
    while ((ch = in.read()) != -1)
        bos.write(ch);
    return bos.toByteArray();
}

For your example, the simplest is to find a few samples : run the C function on it then the java one and compare the results. It should give you informations.