Redid documentation for WebSocketUtil

This commit is contained in:
Cruz Julian Bishop 2012-06-29 15:12:59 +10:00
parent 33c42bee6d
commit 9f9b36f579

View File

@ -19,90 +19,91 @@ import io.netty.buffer.ByteBuf;
import io.netty.buffer.Unpooled; import io.netty.buffer.Unpooled;
import io.netty.handler.codec.base64.Base64; import io.netty.handler.codec.base64.Base64;
import io.netty.util.CharsetUtil; import io.netty.util.CharsetUtil;
import java.security.MessageDigest; import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException; import java.security.NoSuchAlgorithmException;
/** /**
* TODO Document me. * A utility class mainly for use by web sockets
*/ */
final class WebSocketUtil { final class WebSocketUtil {
/** /**
* Performs an MD5 hash * Performs a MD5 hash on the specified data
* *
* @param bytes * @param data The data to hash
* Data to hash * @return The hashed data
* @return Hashed data
*/ */
static byte[] md5(byte[] bytes) { static byte[] md5(byte[] data) {
try { try {
//Try to get a MessageDigest that uses MD5
MessageDigest md = MessageDigest.getInstance("MD5"); MessageDigest md = MessageDigest.getInstance("MD5");
return md.digest(bytes); //Hash the data
return md.digest(data);
} catch (NoSuchAlgorithmException e) { } catch (NoSuchAlgorithmException e) {
throw new InternalError("MD5 not supported on this platform"); //This shouldn't happen! How old is the computer?
throw new InternalError("MD5 not supported on this platform - Outdated?");
} }
} }
/** /**
* Performs an SHA-1 hash * Performs a SHA-1 hash on the specified data
* *
* @param bytes * @param data The data to hash
* Data to hash * @return The hashed data
* @return Hashed data
*/ */
static byte[] sha1(byte[] bytes) { static byte[] sha1(byte[] data) {
try { try {
//Attempt to get a MessageDigest that uses SHA1
MessageDigest md = MessageDigest.getInstance("SHA1"); MessageDigest md = MessageDigest.getInstance("SHA1");
return md.digest(bytes); //Hash the data
return md.digest(data);
} catch (NoSuchAlgorithmException e) { } catch (NoSuchAlgorithmException e) {
throw new InternalError("SHA-1 not supported on this platform"); //Alright, you might have an old system.
throw new InternalError("SHA-1 is not supported on this platform - Outdated?");
} }
} }
/** /**
* Base 64 encoding * Performs base64 encoding on the specified data
* *
* @param bytes * @param data The data to encode
* Bytes to encode * @return An encoded string containing the data
* @return encoded string
*/ */
static String base64(byte[] bytes) { static String base64(byte[] data) {
ByteBuf hashed = Unpooled.wrappedBuffer(bytes); ByteBuf encodedData = Unpooled.wrappedBuffer(data);
return Base64.encode(hashed).toString(CharsetUtil.UTF_8); return Base64.encode(encodedData).toString(CharsetUtil.UTF_8);
} }
/** /**
* Creates some random bytes * Creates an arbitrary number of random bytes
* *
* @param size * @param size the number of random bytes to create
* Number of random bytes to create * @return An array of random bytes
* @return random bytes
*/ */
static byte[] randomBytes(int size) { static byte[] randomBytes(int size) {
byte[] bytes = new byte[size]; byte[] bytes = new byte[size];
for (int i = 0; i < size; i++) { for (int index = 0; index < size; index++) {
bytes[i] = (byte) randomNumber(0, 255); bytes[index] = (byte) randomNumber(0, 255);
} }
return bytes; return bytes;
} }
/** /**
* Generates a random number * Generates a pseudo-random number
* *
* @param min * @param minimum The minimum allowable value
* Minimum value * @param maximum The maximum allowable value
* @param max * @return A pseudo-random number
* Maximum value
* @return Random number
*/ */
static int randomNumber(int min, int max) { static int randomNumber(int minimum, int maximum) {
return (int) (Math.random() * max + min); return (int) (Math.random() * maximum + minimum);
} }
/**
* A private constructor to ensure that instances of this class cannot be made
*/
private WebSocketUtil() { private WebSocketUtil() {
// Unused // Unused
} }