[feature/handle-similar-messages-as-scam] Added a method to hash strings and refactored existing code

Author: Alathreon

application/src/main/java/org/togetherjava/tjbot/features/moderation/scam/ScamHistoryStore.java

@@ -7,7 +7,6 @@
 import org.togetherjava.tjbot.db.generated.tables.records.ScamHistoryRecord;
 import org.togetherjava.tjbot.features.utils.Hashing;
 
-import java.nio.charset.StandardCharsets;
 import java.time.Duration;
 import java.time.Instant;
 import java.util.Collection;
@@ -138,8 +137,7 @@ public void deleteHistoryOlderThan(Instant olderThan) {
      * @return a text representation of the hash
      */
     public static String hashMessageContent(Message message) {
-        return Hashing.bytesToHex(Hashing.hash(HASH_METHOD,
-                message.getContentRaw().getBytes(StandardCharsets.UTF_8)));
+        return Hashing.bytesToHex(Hashing.hashUTF8(HASH_METHOD, message.getContentRaw()));
     }
 
     /**

application/src/main/java/org/togetherjava/tjbot/features/utils/Hashing.java

@@ -57,4 +57,16 @@ public static byte[] hash(String method, byte[] data) {
             throw new IllegalStateException("Hash method must be supported", e);
         }
     }
+
+    /**
+     * Hashes the given UTF 8 text using the given method, see {@link Hashing#hash(String, byte[])}.
+     *
+     * @param method the method to use for hashing, must be supported by {@link MessageDigest}, e.g.
+     *        {@code "SHA"}
+     * @param text the UTF 8 text to hash
+     * @return the computed hash
+     */
+    public static byte[] hashUTF8(String method, String text) {
+        return hash(method, text.getBytes(StandardCharsets.UTF_8));
+    }
 }