fix lab 5 and 6

Lab5/Lab5.java

@@ -8,49 +8,24 @@ import java.util.Map;
 import java.util.Scanner;
 
 class Lab5 {
+
   public static String getGrade(String module, String student, String assessment,
       Map<String, Map<String, Map<String, String>>> db) {
-    Constant<Actually<Map<String, Map<String, Map<String, String>>>>> constantDb = new Constant<>() {
+    Constant<Actually<Map<String, Map<String, Map<String, String>>>>> constantDb = () -> Actually.ok(db);
-      @Override
-      public Actually<Map<String, Map<String, Map<String, String>>>> init() {
-        return Actually.ok(db);
-      }
-    };
 
-    Constant<String> constantNoEntry = new Constant<>() {
+    Constant<String> constantNoEntry = () -> "No such entry";
-      @Override
-      public String init() {
-        return "No such entry";
-      }
-    };
 
-    Immutator<Actually<Map<String, Map<String, String>>>, Map<String, Map<String, Map<String, String>>>> getModule = new Immutator<>() {
+    Immutator<Actually<Map<String, Map<String, String>>>, Map<String, Map<String, Map<String, String>>>> getModule = param -> Actually
-      @Override
+        .ok(param.get(module));
-      public Actually<Map<String, Map<String, String>>> invoke(Map<String, Map<String, Map<String, String>>> param) {
-        return Actually.ok(param.get(module));
-      }
-    };
-    Immutator<Actually<Map<String, String>>, Map<String, Map<String, String>>> getStudent = new Immutator<>() {
-      @Override
-      public Actually<Map<String, String>> invoke(Map<String, Map<String, String>> param) {
-        return Actually.ok(param.get(student));
-      }
-    };
 
-    Immutator<Actually<String>, Map<String, String>> getAssessment = new Immutator<>() {
+    Immutator<Actually<Map<String, String>>, Map<String, Map<String, String>>> getStudent = param -> Actually
-      @Override
+        .ok(param.get(student));
-      public Actually<String> invoke(Map<String, String> param) {
-        return Actually.ok(param.get(assessment).toString());
-      }
 
-    };
+    Immutator<Actually<String>, Map<String, String>> getAssessment = param -> Actually
+        .ok(param.get(assessment).toString());
+
+    return constantDb.init().next(getModule).next(getStudent).next(getAssessment).except(constantNoEntry);
 
-    return constantDb
-      .init()
-      .next(getModule)
-      .next(getStudent)
-      .next(getAssessment)
-      .except(constantNoEntry);
   }
 
   public static void main(String[] args) {

Lab5/cs2030s/fp/Actually.java

@@ -14,9 +14,12 @@ public abstract class Actually<T> implements Immutatorable<T>, Actionable<T> {
     return failure;
   }
 
+  @Override
+  public abstract <R> Actually<R> transform(Immutator<? extends R, ? super T> immutator);
+
   public abstract T unwrap() throws Exception;
 
-  public abstract T except(Constant<? extends T> c);
+  public abstract <U extends T> T except(Constant<? extends U> c);
 
   public abstract void finish(Action<? super T> action);
 
@@ -37,7 +40,7 @@ public abstract class Actually<T> implements Immutatorable<T>, Actionable<T> {
     }
 
     @Override
-    public T except(Constant<? extends T> c) {
+    public <U extends T> T except(Constant<? extends U> c) {
       return this.value;
     }
 
@@ -114,7 +117,7 @@ public abstract class Actually<T> implements Immutatorable<T>, Actionable<T> {
     }
 
     @Override
-    public Object except(Constant<? extends Object> c) {
+    public <U> U except(Constant<? extends U> c) {
       return c.init();
     }
 

Lab6/cs2030s/fp/Actually.java

@@ -16,7 +16,7 @@ public abstract class Actually<T> implements Immutatorable<T>, Actionable<T> {
 
   public abstract T unwrap() throws Exception;
 
-  public abstract T except(Constant<? extends T> c);
+  public abstract <U extends T> T except(Constant<? extends U> c);
 
   public abstract void finish(Action<? super T> action);
 
@@ -37,7 +37,7 @@ public abstract class Actually<T> implements Immutatorable<T>, Actionable<T> {
     }
 
     @Override
-    public T except(Constant<? extends T> c) {
+    public <U extends T> T except(Constant<? extends U> c) {
       return this.value;
     }
 
@@ -114,7 +114,7 @@ public abstract class Actually<T> implements Immutatorable<T>, Actionable<T> {
     }
 
     @Override
-    public Object except(Constant<? extends Object> c) {
+    public <U> U except(Constant<? extends U> c) {
       return c.init();
     }