implemented task 2 completly

src/main/java/cp/CPCommandResponseMessage.java

@@ -7,6 +7,7 @@ import exceptions.IllegalMsgException;
 import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.List;
+import java.util.zip.CRC32;
 
 public class CPCommandResponseMessage extends CPMsg{
 
@@ -77,7 +78,20 @@ public class CPCommandResponseMessage extends CPMsg{
         }
 
 
-        //comparing the CRC checksum
+        // Compare the CRC checksum
+        String receivedChecksumStr = fields[fields.length - 1];
+        long receivedChecksum;
+        try {
+            receivedChecksum = Long.parseLong(receivedChecksumStr, 16);
+        } catch (NumberFormatException e) {
+            throw new IllegalMsgException();
+        }
+
+        long calculatedChecksum = this.calcCRC(reconstructedMessage.toString());
+
+        if (calculatedChecksum != receivedChecksum) {
+            throw new IllegalMsgException();
+        }
 
 
         //sets the received message as the data, so the client can print it on the console

src/main/java/cp/CPCookie.java

@@ -2,18 +2,24 @@ package cp;
 
 public class CPCookie {
 
-    private int cookie;
-    private long createdAt;
-    CPCookie(long createdAt, int cookie){
-        this.createdAt = createdAt;
-        this.cookie = cookie;
+    //error Messages for Cookie Response Message
+    public static final String cookieErrorLimit = "COOKIE_ERR_LIMIT_REACHED";
+    public static final String cookieErrorOldCookie = "COOKIE_ERR_OLD_COOKIE_VALID";
+    public static final String cookieSuccess = "COOKIE_ERR_LIMIT_REACHED";
+
+    private int cookieValue; //"random" Number
+    private long createdAt; //time of Creation as "Unix time"
+    private static final long MAX_LIFETIME_SECONDS = 600; //600 Seconds, according to protocol specification
+    CPCookie(){
+        this.createdAt = System.currentTimeMillis();
+        this.cookieValue = 1;
     }
 
-    public int getCookie() {
-        return cookie;
+    public int getCookieValue() {
+        return cookieValue;
     }
 
-    public long getCreatedAt() {
-        return createdAt;
+    public boolean isStillValid(){
+        return System.currentTimeMillis() - createdAt <= 600; //returns true, if the cookie has lived 600 Seconds or less
     }
 }

src/main/java/cp/CPProtocol.java

@@ -21,7 +21,7 @@ public class CPProtocol extends Protocol {
     private PhyConfiguration PhyConfig;
     private PhyProtocol PhyProto;
     boolean isClient;
-    HashMap<PhyConfiguration, Integer> cookieMap;
+    HashMap<Integer, CPCookie> cookieMap;
     Random rnd;
 
     // Constructor for clients
@@ -39,6 +39,10 @@ public class CPProtocol extends Protocol {
     }
     @Override
     public void send(String s, Configuration config) throws IOException, IWProtocolException {
+        this.send(s, "", config);
+    }
+
+    public void send(String s, String message, Configuration config) throws IOException, IWProtocolException {
 
         if (cookie == null) {
             // Request a new cookie from server
@@ -59,7 +63,7 @@ public class CPProtocol extends Protocol {
 
             //1.2: 1 b
             CPCommandMessage cmdMsg = new CPCommandMessage();
-            cmdMsg.create(cookie, s, "", messageIdCount);
+            cmdMsg.create(cookie, s, message, messageIdCount);
 
             //remembers the id of the current message, so when it's time to receive wel can check if the id's are the same
             this.id = cmdMsg.getMessageId();
@@ -109,14 +113,31 @@ public class CPProtocol extends Protocol {
         return in;
     }
 
-    public void cookieProcesing(PhyConfiguration config, String cookie){
+
+    public void cookieProcesing(PhyConfiguration config, CPCookie cookie) throws IWProtocolException, IOException {
+
 
         if(cookieMap.size() >= CP_HASHMAP_SIZE){
-            System.out.println("Too many cookies.");
+            new CPServerCookieResponseMsg(false,"Cookie limit reached", cookie).sendResponse(this.PhyProto, config);
+            return;
+        }
+
+        CPCookie recievedCookie = cookieMap.get(config.hashCode()); //is null when there is no cookie currently saved
+
+        if(recievedCookie != null){ //if the cookie still exists
+
+            if(recievedCookie.isStillValid()){
+
+                //tells the client that an old cookie has not expired
+                new CPServerCookieResponseMsg(false,"Old Cookie is still valid", cookie).sendResponse(this.PhyProto, config);
+            }else{
+                cookieMap.remove(config.hashCode()); //removes the Cookie, because it has expired
+            }
             return;
         }
 
-        cookieMap.put(config, config.hashCode(cookie));
+        cookieMap.put(config.hashCode(), cookie);
+        new CPServerCookieResponseMsg(true,"Cookie is valid", cookie).sendResponse(this.PhyProto, config);
     }
 
 

src/main/java/cp/CPServerCookieResponseMsg.java

+package cp;
+
+import exceptions.IWProtocolException;
+import phy.PhyConfiguration;
+import phy.PhyProtocol;
+
+import java.io.IOException;
+
+public class CPServerCookieResponseMsg extends CPCookieResponseMsg{
+
+    CPServerCookieResponseMsg(boolean success, String responseMessage, CPCookie cookie){
+        super(success);
+
+        if(success){
+            super.create(String.valueOf(cookie.getCookieValue()));
+        }else {
+            super.create(responseMessage);
+        }
+    }
+
+    public void sendResponse(PhyProtocol phy, PhyConfiguration config) throws IWProtocolException, IOException {
+        phy.send(super.data, config);
+    }
+}

src/main/java/phy/PhyConfiguration.java

@@ -31,23 +31,17 @@ public class PhyConfiguration extends Configuration{
 	public Protocol.proto_id getPid() {return this.pid;}
 
 
-	public boolean equals(PhyConfiguration otherConfig ){
-		return false;
-	}
-	public int hashCode(String cookie){
-		return System.identityHashCode(cookie);
-	}
-
-
-	//generated using Alt+Insert
 	@Override
 	public boolean equals(Object o) {
-		if (this == o) return true;
-		if (!(o instanceof PhyConfiguration that)) return false;
-		return remotePort == that.remotePort && isClient == that.isClient && Objects.equals(remoteIPAddress, that.remoteIPAddress) && pid == that.pid;
+
+		if(o instanceof PhyConfiguration phy1){ //no "null check" needed, because instanceof already covers that
+
+			return phy1.hashCode() == this.hashCode(); //if the hash code is the same, the objects are the same
+		}
+
+		return false;
 	}
 
-	//generated using Alt+Insert
 	@Override
 	public int hashCode() {
 		return Objects.hash(remotePort, remoteIPAddress, pid, isClient);