arma3launcher/src/main/java/de/mc8051/arma3launcher/utils/FileUtils.java

69 lines
2.1 KiB
Java

package de.mc8051.arma3launcher.utils;
import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.nio.charset.Charset;
import java.nio.charset.StandardCharsets;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
/**
* Created by gurkengewuerz.de on 27.03.2020.
*/
public class FileUtils {
public static final Charset DEFAULT_CHARSET;
private static final char[] DIGITS_LOWER;
private static final char[] DIGITS_UPPER;
public static String sha1Hex(File f) throws IOException, NoSuchAlgorithmException {
return encodeHexString(sha1(f));
}
public static byte[] sha1(File file) throws IOException, NoSuchAlgorithmException {
MessageDigest digest = MessageDigest.getInstance("SHA-1");
InputStream fis = new FileInputStream(file);
int n = 0;
byte[] buffer = new byte[8192];
while (n != -1) {
n = fis.read(buffer);
if (n > 0) {
digest.update(buffer, 0, n);
}
}
return digest.digest();
}
public static String encodeHexString(byte[] data) {
return new String(encodeHex(data));
}
public static char[] encodeHex(byte[] data) {
return encodeHex(data, true);
}
public static char[] encodeHex(byte[] data, boolean toLowerCase) {
return encodeHex(data, toLowerCase ? DIGITS_LOWER : DIGITS_UPPER);
}
protected static char[] encodeHex(byte[] data, char[] toDigits) {
int l = data.length;
char[] out = new char[l << 1];
int i = 0;
for(int var5 = 0; i < l; ++i) {
out[var5++] = toDigits[(240 & data[i]) >>> 4];
out[var5++] = toDigits[15 & data[i]];
}
return out;
}
static {
DEFAULT_CHARSET = StandardCharsets.UTF_8;
DIGITS_LOWER = new char[]{'0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'a', 'b', 'c', 'd', 'e', 'f'};
DIGITS_UPPER = new char[]{'0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'A', 'B', 'C', 'D', 'E', 'F'};
}
}