1 files changed, 45 insertions, 26 deletions
diff --git a/src/main/java/org/openslx/imagemaster/util/Hash.java b/src/main/java/org/openslx/imagemaster/util/Hash.java
index 8ac0e5f..24eb595 100644
--- a/src/main/java/org/openslx/imagemaster/util/Hash.java
+++ b/src/main/java/org/openslx/imagemaster/util/Hash.java
@@ -6,7 +6,9 @@ import java.security.NoSuchAlgorithmException;
 
 public class Hash
 {
-	// Cache of md5 digesters
+	/**
+	 * Cache of md5 digesters
+	 */
 	private static final ThreadLocal<MessageDigest> md5hash = new ThreadLocal<MessageDigest>() {
 		@Override
 		public MessageDigest initialValue()
@@ -20,7 +22,9 @@ public class Hash
 			}
 		}
 	};
-	// Cache of sha256 digesters
+	/**
+	 * Cache of sha256 digesters
+	 */
 	private static final ThreadLocal<MessageDigest> sha256hash = new ThreadLocal<MessageDigest>() {
 		@Override
 		public MessageDigest initialValue()
@@ -34,32 +38,35 @@ public class Hash
 			}
 		}
 	};
-	// Cache of sha512 digesters
-	private static final ThreadLocal<MessageDigest> sha512hash = new ThreadLocal<MessageDigest>() {
-		@Override
-		public MessageDigest initialValue()
-		{
-			try {
-				return MessageDigest.getInstance( "SHA-512" );
-			} catch ( NoSuchAlgorithmException e ) {
-				e.printStackTrace();
-				System.exit(1);
-				return null;
-			}
-		}
-	};
-	// For converting to hex string
+	/**
+	 * For converting to hex string
+	 */
 	private static final char[] HEX_CHARS = { '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'A', 'B', 'C', 'D', 'E', 'F' };
-	// Constant
+	/**
+	 * Constant for the utf-8 charset, saves repeated lookups
+	 */
 	private static final Charset UTF8 = Charset.forName( "UTF-8" );
 
 	// MD5
 	
+	/**
+	 * Compute md5 hash of given binary data.
+	 * 
+	 * @param bytes the binary data in a byte array
+	 * @return hex representation of the 128bit md5 hash
+	 */
 	public static String md5( final byte[] bytes )
 	{
 		return toHexString( md5hash.get().digest( bytes ) );
 	}
 	
+	/**
+	 * Compute md5 hash of the given string.
+	 * The string will be converted to utf-8 before computation.
+	 * 
+	 * @param text the text to hash
+	 * @return hex representation of the 128bit md5 hash
+	 */
 	public static String md5( final String text )
 	{
 		return md5( text.getBytes( UTF8 ));
@@ -67,25 +74,37 @@ public class Hash
 	
 	// SHA-256
 	
+	/**
+	 * Compute sha256 hash of given binary data.
+	 * 
+	 * @param bytes the binary data in a byte array
+	 * @return hex representation of the 256bit sha256 hash
+	 */
 	public static String sha256( final byte[] bytes )
 	{
 		return toHexString( sha256hash.get().digest( bytes ) );
 	}
-	
+
+	/**
+	 * Compute sha256 hash of the given string.
+	 * The string will be converted to utf-8 before computation.
+	 * 
+	 * @param text the text to hash
+	 * @return hex representation of the 256bit sha256 hash
+	 */
 	public static String sha256( final String text )
 	{
 		return sha256( text.getBytes( UTF8 ));
 	}
 	
-	// SHA-512
-	
-	public static MessageDigest getSha512Digest()
-	{
-		return sha512hash.get();
-	}
-
 	// Helper
 	
+	/**
+	 * Convert given binary data to hex.
+	 * 
+	 * @param bytes binary data in a byte array
+	 * @return upper case hex representation of bytes 
+	 */
 	private static String toHexString( final byte[] bytes )
 	{
 		final char[] hexChars = new char[bytes.length * 2];