clean code

src/main/java/de/jalin/fedipage/FediServlet.java

@@ -18,8 +18,8 @@ import jakarta.servlet.http.HttpServletResponse;
 
 public class FediServlet extends HttpServlet {
 
-	private static final long serialVersionUID = 1L;
-
+	private static final long serialVersionUID = 2357332474144454738L;
+	
 	private VelocityEngine velocityEngine;
 	private String instance;
 	private String account;

src/main/java/de/jalin/fedipage/PostDateFormatter.java

@@ -1,17 +1,20 @@
 package de.jalin.fedipage;
 
+import java.io.Serializable;
 import java.text.ParseException;
 import java.text.SimpleDateFormat;
 import java.util.Date;
 
-public class PostDateFormatter {
+public class PostDateFormatter implements Serializable {
 
-	final SimpleDateFormat dfTimestamp;
-	final SimpleDateFormat dfEuropean;
+	private static final long serialVersionUID = 1661651668644302982L;
+	
+	final SimpleDateFormat jsonTimestampDateformat;
+	final SimpleDateFormat europeanDateformat;
 	
 	public PostDateFormatter() {
-		dfTimestamp = new SimpleDateFormat("yyyy-MM-dd");
-		dfEuropean = new SimpleDateFormat("dd.MM.yyyy");
+		jsonTimestampDateformat = new SimpleDateFormat("yyyy-MM-dd");
+		europeanDateformat = new SimpleDateFormat("dd.MM.yyyy");
 	}
 	
 	public String format(final String timestamp) {
@@ -22,18 +25,22 @@ public class PostDateFormatter {
 			return timestamp;
 		}
 		long now = System.currentTimeMillis();
-		if (timestamp.startsWith(dfTimestamp.format(new Date(now)))) {
+		if (timestamp.startsWith(jsonTimestampDateformat.format(new Date(now)))) {
 			return "heute";
 		}
-		if (timestamp.startsWith(dfTimestamp.format(new Date(now - (24*60*60*1000L))))) {
+		final long oneDayMillis = 24*60*60*1000L;
+		if (timestamp.startsWith(jsonTimestampDateformat.format(new Date(now - oneDayMillis)))) {
 			return "gestern";
 		}
+		if (timestamp.startsWith(jsonTimestampDateformat.format(new Date(now - oneDayMillis - oneDayMillis)))) {
+			return "vorgestern";
+		}
+		final String timeStampDate = timestamp.substring(0, 10);
 		try {
-			final Date date = dfTimestamp.parse(timestamp.substring(0, 10));
-			return dfEuropean.format(date);
+			return europeanDateformat.format(jsonTimestampDateformat.parse(timeStampDate));
 		} catch (ParseException e) {
 		}
-		return timestamp.substring(0, 10);
+		return timeStampDate;
 	}
 	
 }