Merge pull request #21 from RIT-SWEN-262/league-model

League model

22 files changed, 750 insertions, 172 deletions

diff --git a/pom.xml b/pom.xml
index 6e37b12..2333fd8 100644
--- a/pom.xml
+++ b/pom.xml
@@ -42,6 +42,11 @@
             <artifactId>jackson-datatype-jdk8</artifactId>
             <version>2.20.0</version>
         </dependency>
+        <dependency>
+            <groupId>com.fasterxml.jackson.dataformat</groupId>
+            <artifactId>jackson-dataformat-xml</artifactId>
+            <version>2.20.0</version>
+        </dependency>
     </dependencies>
     <build>
         <plugins>
@@ -67,8 +72,8 @@
                 <artifactId>jacoco-maven-plugin</artifactId>
                 <version>0.8.11</version>
                 <configuration>
-                    <destfile>/target/coverage-reports/jacoco-unit.exec</destfile>
-                    <datafile>/target/coverage-reports/jacoco-unit.exec</datafile>
+                    <destFile>/target/coverage-reports/jacoco-unit.exec</destFile>
+                    <destFile>/target/coverage-reports/jacoco-unit.exec</destFile>
                 </configuration>
                 <executions>
                     <execution>
diff --git a/src/main/java/design/controller/userinput/Menu.java b/src/main/java/design/controller/userinput/Menu.java
index ab633e1..01e80a9 100644
--- a/src/main/java/design/controller/userinput/Menu.java
+++ b/src/main/java/design/controller/userinput/Menu.java
@@ -23,7 +23,7 @@ public abstract class Menu {
         try {
             int i = Integer.parseInt(line) - 1;
             menuOptions.get(i).onAction();
-        } catch (IndexOutOfBoundsException ex) {
+        } catch (IndexOutOfBoundsException | NumberFormatException ex) {
             System.err.printf("Invalid option \"%s\"\n", line);
             present();
         }
diff --git a/src/main/java/design/controller/userinput/menus/ImportExportMenu.java b/src/main/java/design/controller/userinput/menus/ImportExportMenu.java
new file mode 100644
index 0000000..21ffa6c
--- /dev/null
+++ b/src/main/java/design/controller/userinput/menus/ImportExportMenu.java
@@ -0,0 +1,81 @@
+package design.controller.userinput.menus;
+
+import design.controller.userinput.Menu;
+import design.controller.userinput.MenuOption;
+import design.persistence.*;
+import design.persistence.importexport.DataHandler;
+import design.persistence.importexport.DataSource;
+import design.persistence.importexport.JSONHandler;
+import design.persistence.importexport.XMLHandler;
+
+import java.io.File;
+import java.io.IOException;
+import java.util.List;
+import java.util.Scanner;
+
+public class ImportExportMenu extends Menu {
+
+    @Override
+    public String getTitle() {
+        return "import export menu";
+    }
+
+   @Override
+    public List<MenuOption> getMenuOptions() {
+        List<MenuOption> opts = new java.util.ArrayList<>();
+
+
+        opts.add(new MenuOption("return to main menu", () -> new MainMenu().present()));
+
+        opts.add(new MenuOption("import leagues...", () -> promptForPath(true, false)));
+        opts.add(new MenuOption("export leagues...", () -> promptForPath(false, false)));
+        opts.add(new MenuOption("import profiles...", () -> promptForPath(true, true)));
+        opts.add(new MenuOption("export profiles...", () -> promptForPath(false, true)));
+
+        return opts;
+    }
+
+    private void promptForPath(boolean isImporting, boolean isPersonalProfile)
+    {
+        System.out.print("Enter file path: ");
+        Scanner sc = new Scanner(System.in);
+        String filePath = sc.nextLine();
+        File file = new File(filePath);
+
+        DataSource source;
+        if (isPersonalProfile) {
+            source = PersonalDatabase.instance();
+        } else {
+            source = LeagueDatabase.instance();
+        }
+
+        DataHandler handler;
+        String ext = getExtension(filePath);
+        switch (ext) {
+            case "json" -> handler = new JSONHandler(source);
+            case "xml" -> handler = new XMLHandler(source);
+            default -> {
+                System.out.println("Unsupported file type: " + ext);
+                this.present();
+                return;
+            }
+        }
+
+        try {
+            if (isImporting) {
+                handler.importData(file);
+            } else {
+                handler.exportData(file);
+            }
+        } catch (IOException e) {
+            throw new RuntimeException(e);
+        }
+
+        this.present();
+    }
+
+    private static String getExtension(String fileName) {
+        int i = fileName.lastIndexOf('.');
+        return (i >= 0) ? fileName.substring(i + 1).toLowerCase() : "unknown";
+    }
+}
diff --git a/src/main/java/design/controller/userinput/menus/MainMenu.java b/src/main/java/design/controller/userinput/menus/MainMenu.java
index 4331e56..3f520e4 100644
--- a/src/main/java/design/controller/userinput/menus/MainMenu.java
+++ b/src/main/java/design/controller/userinput/menus/MainMenu.java
@@ -27,6 +27,7 @@ public class MainMenu extends Menu {
             options.add(new MenuOption("statistics...", () -> new StatisticsMenu().present()));
             options.add(new MenuOption("log round...", () -> new HolePlayMenu().present()));
             options.add(new MenuOption("league play...", () -> new SelectLeague().present()));
+            options.add(new MenuOption("manage data...", () -> new ImportExportMenu().present()));
         }
         return options;
     }
diff --git a/src/main/java/design/controller/userinput/menus/SelectLeague.java b/src/main/java/design/controller/userinput/menus/SelectLeague.java
index 08f6c91..e1675e9 100644
--- a/src/main/java/design/controller/userinput/menus/SelectLeague.java
+++ b/src/main/java/design/controller/userinput/menus/SelectLeague.java
@@ -26,7 +26,7 @@ public class SelectLeague extends Menu {
     public List<MenuOption> getMenuOptions() {
         List<MenuOption> options = new ArrayList<>();
         for (League l : LeagueDatabase.instance().getLeagues()) {
-            options.add(new MenuOption(l.getName(), () -> {
+            options.add(new MenuOption(l.toString(), () -> {
                 if (l instanceof ScrambleLeague sl && sl.locateTeam(golfer) == null) {
                     Scanner sc = new Scanner(System.in);
                     System.out.print("You are not a member of a team for this league. Would you like to create one (Y/n): ");
diff --git a/src/main/java/design/model/Golfer.java b/src/main/java/design/model/Golfer.java
index 6ea9d32..4fb521e 100644
--- a/src/main/java/design/model/Golfer.java
+++ b/src/main/java/design/model/Golfer.java
@@ -1,6 +1,7 @@
 package design.model;
 
 import com.fasterxml.jackson.annotation.JsonCreator;
+import com.fasterxml.jackson.annotation.JsonProperty;
 import com.fasterxml.jackson.annotation.JsonPropertyOrder;
 
 import java.util.ArrayList;
@@ -18,10 +19,14 @@ public class Golfer implements Originator {
     private final List<Round> rounds;
     private final List<Club> clubs; // Keep track of golfer's clubs
     private int nextClubId;
+    private final List<Invite> invites;
+    private Team joinedTeam;
 
+
+    
     @JsonCreator
     private Golfer(String username, int passwordHash, String fullName, List<Course> courses, List<Round> rounds,
-            List<Club> clubs) {
+            List<Club> clubs, List<Invite> invites, Team joinedTeam) {
         this.username = username;
         this.passwordHash = passwordHash;
         this.fullName = fullName;
@@ -29,6 +34,8 @@ public class Golfer implements Originator {
         this.rounds = rounds;
         this.clubs = clubs;
         this.nextClubId = this.clubs.stream().mapToInt(Club::getId).max().orElse(0) + 1;
+        this.invites = invites;
+        this.joinedTeam = joinedTeam;
     }
 
     public Golfer(String fullName, String username, String password) {
@@ -39,6 +46,8 @@ public class Golfer implements Originator {
         this.rounds = new ArrayList<>();
         this.clubs = new ArrayList<>();
         this.nextClubId = 1;
+        this.invites = new ArrayList<>();
+        this.joinedTeam = null;
     }
 
     public String getUsername() {
@@ -160,5 +169,21 @@ public class Golfer implements Originator {
         this.clubs.addAll(gm.clubs);
 
         this.nextClubId = gm.nextClubId;
-     }
+    }
+
+    public boolean joinTeam(Team team){
+        for(Invite invite : invites){
+            if(invite.getTeam().equals(team)){
+                this.joinedTeam = team;
+                team.addMember(this);
+                invites.remove(invite);
+                return true;
+            }
+        }
+        return false;
+    }
+
+    public Team getTeam(){
+        return joinedTeam;
+    }
 }
diff --git a/src/main/java/design/model/League.java b/src/main/java/design/model/League.java
index 881e25f..8793c86 100644
--- a/src/main/java/design/model/League.java
+++ b/src/main/java/design/model/League.java
@@ -25,6 +25,7 @@ public abstract class League {
     private final Date endDate;
     private final Golfer owner;
     private final List<Match> schedule;
+    private boolean completed;
 
     @JsonCreator
     protected League(int id, String name, Date registrationDate, Date startDate, Date endDate, Golfer owner, List<Match> schedule) {
@@ -35,6 +36,7 @@ public abstract class League {
         this.endDate = endDate;
         this.owner = owner;
         this.schedule = schedule != null ? schedule : new ArrayList<>();
+        this.completed = false;
     }
 
     public League(String name, Date registrationDate, Date startDate, Date endDate, Golfer owner) {
@@ -45,6 +47,7 @@ public abstract class League {
         this.endDate = endDate;
         this.owner = owner;
         this.schedule = new ArrayList<>();
+        this.completed = false;
     }
 
     public int getId() {
@@ -75,9 +78,12 @@ public abstract class League {
         return schedule.toArray(Match[]::new);
     }
 
+    public boolean isCompleted() {
+        return completed;
+    }
+
     public void addMatchToSchedule(Match match) {
-        Date date = match.getDateScheduled();
-        if(date.after(endDate)){
+        if(match.getDateScheduled().after(endDate)){
             throw new IllegalArgumentException("Cannot create match after league has ended");
         }
         schedule.add(match);
@@ -87,4 +93,23 @@ public abstract class League {
         assert this.id == -1;
         this.id = id;
     }
+
+    public abstract String getType();
+
+    @Override
+    public String toString() {
+        return String.format("%s - %s", name, getType());
+    }
+    public boolean isPlayable() {
+        Date now = new Date();
+        return now.after(startDate) && now.before(endDate);
+    }
+
+    public void markCompleted(){
+        this.completed = true;
+    }
+
+    public abstract void recordPlay(Golfer player, Match match, Round round);
+
+    public abstract void finalizeLeague();
 }
diff --git a/src/main/java/design/model/ScrambleLeague.java b/src/main/java/design/model/ScrambleLeague.java
index b0d65f8..1fb8f1d 100644
--- a/src/main/java/design/model/ScrambleLeague.java
+++ b/src/main/java/design/model/ScrambleLeague.java
@@ -4,30 +4,41 @@ import com.fasterxml.jackson.annotation.JsonCreator;
 import com.fasterxml.jackson.annotation.JsonTypeName;
 
 import java.util.ArrayList;
+import java.util.Collections;
+import java.util.Comparator;
 import java.util.Date;
+import java.util.HashMap;
 import java.util.List;
+import java.util.Map;
 
 @JsonTypeName("scramble")
 public class ScrambleLeague extends League {
-    private final List<Team> participants;
+    private List<Team> participants;
+    private Map<Team, Integer> totalTeamScores;
 
     @JsonCreator
     private ScrambleLeague(int id, String name, Date registrationDate, Date startDate, Date endDate, Golfer owner, List<Team> participants, List<Match> schedule) {
         super(id, name, registrationDate, startDate, endDate, owner, schedule);
         this.participants = participants;
+        this.totalTeamScores = new HashMap<>();
+        participants.forEach(t -> totalTeamScores.putIfAbsent(t, 0));
     }
 
     public ScrambleLeague(String name, Date registrationDate, Date startDate, Date endDate, Golfer owner) {
         super(name, registrationDate, startDate, endDate, owner);
         this.participants = new ArrayList<>();
+        this.totalTeamScores = new HashMap<>();
     }
 
-    public boolean addParticipants(Team e) {
-        return participants.add(e);
+    public boolean addParticipants(Team t) {
+        boolean added = participants.add(t);
+        if(added) totalTeamScores.putIfAbsent(t, 0);
+        return added;
     }
 
-    public boolean removeParticipants(Team o) {
-        return participants.remove(o);
+    public boolean removeParticipants(Team t) {
+        totalTeamScores.remove(t);
+        return participants.remove(t);
     }
 
     public Team[] getParticipants() {
@@ -42,4 +53,32 @@ public class ScrambleLeague extends League {
         }
         return null;
     }
+
+    @Override
+    public String getType() {
+        return "scramble";
+    }
+    @Override
+    public void recordPlay(Golfer player, Match match, Round round){
+        if(!isPlayable()) return;
+        Team team = player.getTeam();
+        if (team == null) return;
+        int strokes = round.getTotalSwings();
+        team.addMemberRound(player, strokes);
+        match.addRound(round);
+    }
+
+    @Override
+    public void finalizeLeague(){
+        markCompleted();
+        for(Team team : participants){
+            int score = team.computeTotalBestScore();
+            totalTeamScores.put(team, score);
+        }
+        participants.sort(Comparator.comparingInt(totalTeamScores::get));
+    }
+
+    public Map<Team, Integer> getTotalTeamScores(){
+        return Collections.unmodifiableMap(totalTeamScores);
+    }
 }
diff --git a/src/main/java/design/model/StrokeLeague.java b/src/main/java/design/model/StrokeLeague.java
index 2b787b5..d051fd0 100644
--- a/src/main/java/design/model/StrokeLeague.java
+++ b/src/main/java/design/model/StrokeLeague.java
@@ -4,33 +4,65 @@ import com.fasterxml.jackson.annotation.JsonCreator;
 import com.fasterxml.jackson.annotation.JsonTypeName;
 
 import java.util.ArrayList;
+import java.util.Collections;
+import java.util.Comparator;
 import java.util.Date;
+import java.util.HashMap;
 import java.util.List;
+import java.util.Map;
 
 @JsonTypeName("stroke")
 public class StrokeLeague extends League {
-    private final List<Golfer> participants;
+    private List<Golfer> participants;
+    private Map<Golfer, Integer> totalStrokes;
 
     @JsonCreator
     private StrokeLeague(int id, String name, Date registrationDate, Date startDate, Date endDate, Golfer owner, List<Golfer> participants, List<Match> schedule) {
         super(id, name, registrationDate, startDate, endDate, owner, schedule);
         this.participants = participants;
+        this.totalStrokes = new HashMap<>();
+        participants.forEach(p -> totalStrokes.putIfAbsent(p, 0));
     }
 
     public StrokeLeague(String name, Date registrationDate, Date startDate, Date endDate, Golfer owner) {
         super(name, registrationDate, startDate, endDate, owner);
         this.participants = new ArrayList<>();
+        this.totalStrokes = new HashMap<>();
     }
 
-    public boolean addParticipants(Golfer e) {
-        return participants.add(e);
+    public boolean addParticipants(Golfer g) {
+        boolean added = participants.add(g);
+        if(added) totalStrokes.putIfAbsent(g, 0);
+        return added;
     }
 
-    public boolean removeParticipants(Golfer o) {
-        return participants.remove(o);
+    public boolean removeParticipants(Golfer g) {
+        totalStrokes.remove(g);
+        return participants.remove(g);
     }
 
     public Golfer[] getParticipants() {
         return participants.toArray(Golfer[]::new);
     }
+
+    @Override
+    public String getType() {
+        return "stroke";
+    }
+    public void recordPlay(Golfer player, Match match, Round round){
+        if(!isPlayable() || !participants.contains(player)) return;
+        int strokes = round.getTotalSwings();
+        totalStrokes.merge(player, strokes, Integer::sum);
+        match.addRound(round);
+    }
+
+    @Override
+    public void finalizeLeague(){
+        markCompleted();
+        participants.sort(Comparator.comparingInt(totalStrokes::get));
+    }
+    
+    public Map<Golfer, Integer> getTotalStrokes(){
+        return Collections.unmodifiableMap(totalStrokes);
+    }
 }
diff --git a/src/main/java/design/model/Team.java b/src/main/java/design/model/Team.java
index 53b276e..8f30468 100644
--- a/src/main/java/design/model/Team.java
+++ b/src/main/java/design/model/Team.java
@@ -1,17 +1,22 @@
 package design.model;
 
 import java.util.ArrayList;
+import java.util.HashMap;
 import java.util.List;
+import java.util.Map;
+import java.util.Objects;
 
 public class Team {
     private String name;
     private final List<Golfer> members;
+    private final Map<Golfer, Integer> memberBestRounds;
     private final Golfer owner;
 
     public Team(String name, Golfer owner) {
         this.name = name;
         this.owner = owner;
         this.members = new ArrayList<>();
+        this.memberBestRounds = new HashMap<>();
     }
 
     public String getName() {
@@ -27,14 +32,40 @@ public class Team {
     }
 
     public boolean addMember(Golfer golfer) {
+        if(members.size() >= 4){
+            throw new IllegalArgumentException("Team size limit reached!");
+        }
         return members.add(golfer);
     }
 
     public boolean removeMember(Golfer g) {
+        memberBestRounds.remove(g);
         return members.remove(g);
     }
 
     public Golfer getOwner() {
         return owner;
     }
+
+    public void addMemberRound(Golfer g, int strokes){
+        memberBestRounds.merge(g, strokes, Math::min);
+    }
+
+    public int computeTotalBestScore(){
+        if(memberBestRounds.isEmpty()) return 100; // Bad Score Penalty for not playing
+        return memberBestRounds.values().stream().min(Integer::compareTo).orElse(100);
+    }
+
+    @Override
+    public boolean equals(Object obj) {
+        if (this == obj) return true;
+        if (obj == null || getClass() != obj.getClass()) return false;
+        Team other = (Team) obj;
+        return Objects.equals(name, other.name) && Objects.equals(owner, other.owner);
+    }
+
+    @Override
+    public int hashCode() {
+        return Objects.hash(name, owner);
+    }
 }
diff --git a/src/main/java/design/persistence/JSONLeagueDatabase.java b/src/main/java/design/persistence/JSONLeagueDatabase.java
index 42fa000..b5f4bc3 100644
--- a/src/main/java/design/persistence/JSONLeagueDatabase.java
+++ b/src/main/java/design/persistence/JSONLeagueDatabase.java
@@ -1,14 +1,7 @@
 package design.persistence;
 
-import com.fasterxml.jackson.annotation.JsonAutoDetect;
-import com.fasterxml.jackson.annotation.JsonCreator;
-import com.fasterxml.jackson.annotation.PropertyAccessor;
-import com.fasterxml.jackson.core.StreamReadFeature;
 import com.fasterxml.jackson.databind.*;
-import com.fasterxml.jackson.databind.json.JsonMapper;
 import com.fasterxml.jackson.databind.module.SimpleModule;
-import com.fasterxml.jackson.datatype.jsr310.JavaTimeModule;
-import com.fasterxml.jackson.module.paramnames.ParameterNamesModule;
 import design.model.Course;
 import design.model.Golfer;
 import design.model.League;
@@ -44,18 +37,10 @@ public class JSONLeagueDatabase implements LeagueDatabase {
     public JSONLeagueDatabase(String filename) {
         this.file = new File(filename);
         this.cache = new HashMap<>();
-        this.mapper = JsonMapper.builder().enable(StreamReadFeature.INCLUDE_SOURCE_IN_LOCATION).build();
+        this.mapper = new ObjectMapper();
 
-        SimpleModule module = new SimpleModule();
-        module.addDeserializer(Course.class, new Serializers.CourseIdDeserializer());
-        module.addSerializer(Course.class, new Serializers.CourseIdSerializer());
-        module.addDeserializer(Golfer.class, new Serializers.GolferUsernameDeserializer());
-        module.addSerializer(Golfer.class, new Serializers.GolferUsernameSerializer());
-        mapper.configure(DeserializationFeature.FAIL_ON_UNKNOWN_PROPERTIES, false);
-        mapper.registerModule(module);
-        mapper.setVisibility(PropertyAccessor.FIELD, JsonAutoDetect.Visibility.ANY);
-        mapper.registerModule(new ParameterNamesModule(JsonCreator.Mode.PROPERTIES));
-        mapper.registerModule(new JavaTimeModule());
+        Serializers.configureMapper(mapper);
+        mapper.registerModule(this.getJacksonModule());
 
         try {
             load();
@@ -105,4 +90,36 @@ public class JSONLeagueDatabase implements LeagueDatabase {
         cache.put(league.getId(), league);
         save();
     }
+
+    @Override
+    public void importData(Object rawData) throws IOException {
+        if (!(rawData instanceof League[] data)) {
+            throw new ClassCastException();
+        }
+        cache.clear();
+        for (League league : data) {
+            cache.put(league.getId(), league);
+        }
+        save();
+    }
+
+    @Override
+    public League[] exportData() {
+        return getLeagues();
+    }
+
+    @Override
+    public SimpleModule getJacksonModule() {
+        SimpleModule module = new SimpleModule();
+        module.addDeserializer(Course.class, new Serializers.CourseIdDeserializer());
+        module.addSerializer(Course.class, new Serializers.CourseIdSerializer());
+        module.addDeserializer(Golfer.class, new Serializers.GolferUsernameDeserializer());
+        module.addSerializer(Golfer.class, new Serializers.GolferUsernameSerializer());
+        return module;
+    }
+
+    @Override
+    public Class<?> getTargetClass() {
+        return League[].class;
+    }
 }
diff --git a/src/main/java/design/persistence/JSONPersonalDatabase.java b/src/main/java/design/persistence/JSONPersonalDatabase.java
index 7f55f78..e035ae4 100644
--- a/src/main/java/design/persistence/JSONPersonalDatabase.java
+++ b/src/main/java/design/persistence/JSONPersonalDatabase.java
@@ -1,14 +1,7 @@
 package design.persistence;
 
-import com.fasterxml.jackson.annotation.JsonAutoDetect;
-import com.fasterxml.jackson.annotation.JsonCreator;
-import com.fasterxml.jackson.annotation.PropertyAccessor;
-import com.fasterxml.jackson.core.StreamReadFeature;
 import com.fasterxml.jackson.databind.*;
-import com.fasterxml.jackson.databind.json.JsonMapper;
 import com.fasterxml.jackson.databind.module.SimpleModule;
-import com.fasterxml.jackson.datatype.jsr310.JavaTimeModule;
-import com.fasterxml.jackson.module.paramnames.ParameterNamesModule;
 import design.model.Course;
 import design.model.Golfer;
 import design.model.League;
@@ -42,21 +35,10 @@ public class JSONPersonalDatabase implements PersonalDatabase {
     private JSONPersonalDatabase(String filename) {
         this.file = new File(filename);
         this.cache = new HashMap<>();
-        this.mapper = JsonMapper.builder().enable(StreamReadFeature.INCLUDE_SOURCE_IN_LOCATION).build();;
+        this.mapper = new ObjectMapper();
 
-        // TODO: Once the saved JSON matches the model, consider removing.
-        // TEMP: tolerate unknown props while the model stabilizes
-        mapper.configure(DeserializationFeature.FAIL_ON_UNKNOWN_PROPERTIES, false);
-
-        SimpleModule module = new SimpleModule();
-        module.addDeserializer(Course.class, new Serializers.CourseIdDeserializer());
-        module.addSerializer(Course.class, new Serializers.CourseIdSerializer());
-        module.addSerializer(League.class, new Serializers.LeagueIDSerializer());
-        module.addDeserializer(League.class, new Serializers.LeagueIDDeserializer());
-        mapper.registerModule(module);
-        mapper.setVisibility(PropertyAccessor.FIELD, JsonAutoDetect.Visibility.ANY);
-        mapper.registerModule(new ParameterNamesModule(JsonCreator.Mode.PROPERTIES));
-        mapper.registerModule(new JavaTimeModule());
+        Serializers.configureMapper(mapper);
+        mapper.registerModule(this.getJacksonModule());
 
         try {
             load();
@@ -106,4 +88,36 @@ public class JSONPersonalDatabase implements PersonalDatabase {
         cache.put(golfer.getUsername(), golfer);
         save();
     }
+
+    @Override
+    public void importData(Object rawData) throws IOException {
+        if (!(rawData instanceof Golfer[] data)) {
+            throw new ClassCastException();
+        }
+        cache.clear();
+        for (Golfer golfer : data) {
+            cache.put(golfer.getUsername(), golfer);
+        }
+        save();
+    }
+
+    @Override
+    public Golfer[] exportData() {
+        return getGolfers();
+    }
+
+    @Override
+    public SimpleModule getJacksonModule() {
+        SimpleModule module = new SimpleModule();
+        module.addDeserializer(Course.class, new Serializers.CourseIdDeserializer());
+        module.addSerializer(Course.class, new Serializers.CourseIdSerializer());
+        module.addSerializer(League.class, new Serializers.LeagueIDSerializer());
+        module.addDeserializer(League.class, new Serializers.LeagueIDDeserializer());
+        return module;
+    }
+
+    @Override
+    public Class<?> getTargetClass() {
+        return Golfer[].class;
+    }
 }
diff --git a/src/main/java/design/persistence/LeagueDatabase.java b/src/main/java/design/persistence/LeagueDatabase.java
index 953624d..ed6ddae 100644
--- a/src/main/java/design/persistence/LeagueDatabase.java
+++ b/src/main/java/design/persistence/LeagueDatabase.java
@@ -1,10 +1,11 @@
 package design.persistence;
 
 import design.model.League;
+import design.persistence.importexport.DataSource;
 
 import java.io.IOException;
 
-public interface LeagueDatabase {
+public interface LeagueDatabase extends DataSource {
     static LeagueDatabase instance() {
         return JSONLeagueDatabase.instance();
     }
@@ -18,4 +19,10 @@ public interface LeagueDatabase {
     void removeLeague(League league) throws IOException;
 
     void updateLeague(League league) throws IOException;
+
+    @Override
+    void importData(Object data) throws IOException;
+
+    @Override
+    Object exportData() throws IOException;
 }
diff --git a/src/main/java/design/persistence/PersonalDatabase.java b/src/main/java/design/persistence/PersonalDatabase.java
index adb865d..70dd37d 100644
--- a/src/main/java/design/persistence/PersonalDatabase.java
+++ b/src/main/java/design/persistence/PersonalDatabase.java
@@ -1,9 +1,11 @@
 package design.persistence;
 
 import design.model.Golfer;
+import design.persistence.importexport.DataSource;
+
 import java.io.IOException;
 
-public interface PersonalDatabase {
+public interface PersonalDatabase extends DataSource {
 
     static PersonalDatabase instance() {
         return JSONPersonalDatabase.instance();
@@ -18,4 +20,10 @@ public interface PersonalDatabase {
     void removeGolfer(Golfer golfer) throws IOException;
 
     void updateGolfer(Golfer golfer) throws IOException;
+
+    @Override
+    void importData(Object data) throws IOException;
+
+    @Override
+    Object exportData() throws IOException;
 }
diff --git a/src/main/java/design/persistence/Serializers.java b/src/main/java/design/persistence/Serializers.java
index 3940b44..246dbf1 100644
--- a/src/main/java/design/persistence/Serializers.java
+++ b/src/main/java/design/persistence/Serializers.java
@@ -1,18 +1,20 @@
 package design.persistence;
 
+import com.fasterxml.jackson.annotation.*;
 import com.fasterxml.jackson.core.JsonGenerator;
 import com.fasterxml.jackson.core.JsonParser;
 import com.fasterxml.jackson.core.util.DefaultIndenter;
 import com.fasterxml.jackson.core.util.DefaultPrettyPrinter;
-import com.fasterxml.jackson.databind.DeserializationContext;
-import com.fasterxml.jackson.databind.JsonDeserializer;
-import com.fasterxml.jackson.databind.JsonSerializer;
-import com.fasterxml.jackson.databind.SerializerProvider;
+import com.fasterxml.jackson.databind.*;
+import com.fasterxml.jackson.datatype.jsr310.JavaTimeModule;
+import com.fasterxml.jackson.module.paramnames.ParameterNamesModule;
 import design.model.Course;
 import design.model.Golfer;
 import design.model.League;
 
 import java.io.IOException;
+import java.time.LocalDateTime;
+import java.util.List;
 
 public class Serializers {
     public static class CustomPrettyPrinter extends DefaultPrettyPrinter {
@@ -76,4 +78,19 @@ public class Serializers {
             return personalDB.getGolfer(username);
         }
     }
+
+    public static class DateTimeStringSerializer extends JsonSerializer<LocalDateTime> {
+        @Override
+        public void serialize(LocalDateTime value, JsonGenerator gen, SerializerProvider serializers) throws IOException {
+            gen.writeString(value.toString());
+        }
+    }
+
+    public static void configureMapper(ObjectMapper mapper) {
+        mapper.configure(DeserializationFeature.FAIL_ON_UNKNOWN_PROPERTIES, false);
+        mapper.setVisibility(PropertyAccessor.FIELD, JsonAutoDetect.Visibility.ANY);
+        mapper.registerModule(new ParameterNamesModule(JsonCreator.Mode.PROPERTIES));
+        mapper.registerModule(new JavaTimeModule());
+        mapper.configOverride(List.class).setSetterInfo(JsonSetter.Value.forValueNulls(Nulls.AS_EMPTY));
+    }
 }
diff --git a/src/main/java/design/persistence/importexport/DataHandler.java b/src/main/java/design/persistence/importexport/DataHandler.java
new file mode 100644
index 0000000..59df9be
--- /dev/null
+++ b/src/main/java/design/persistence/importexport/DataHandler.java
@@ -0,0 +1,11 @@
+package design.persistence.importexport;
+
+import java.io.File;
+import java.io.IOException;
+
+public interface DataHandler {
+
+    void importData(File file) throws IOException;
+
+    void exportData(File file) throws IOException;
+}
diff --git a/src/main/java/design/persistence/importexport/DataSource.java b/src/main/java/design/persistence/importexport/DataSource.java
new file mode 100644
index 0000000..e735c7e
--- /dev/null
+++ b/src/main/java/design/persistence/importexport/DataSource.java
@@ -0,0 +1,16 @@
+package design.persistence.importexport;
+
+import com.fasterxml.jackson.databind.module.SimpleModule;
+
+import java.io.IOException;
+
+public interface DataSource {
+
+    void importData(Object data) throws IOException;
+
+    Object exportData() throws IOException;
+
+    SimpleModule getJacksonModule();
+
+    Class<?> getTargetClass();
+}
\ No newline at end of file
diff --git a/src/main/java/design/persistence/importexport/JSONHandler.java b/src/main/java/design/persistence/importexport/JSONHandler.java
new file mode 100644
index 0000000..9c04281
--- /dev/null
+++ b/src/main/java/design/persistence/importexport/JSONHandler.java
@@ -0,0 +1,35 @@
+package design.persistence.importexport;
+import com.fasterxml.jackson.databind.ObjectMapper;
+import com.fasterxml.jackson.databind.json.JsonMapper;
+import design.persistence.Serializers;
+
+import java.io.File;
+import java.io.IOException;
+
+public class JSONHandler implements DataHandler {
+
+    private final DataSource dataSource;
+    private final ObjectMapper jsonMapper = new JsonMapper();
+
+    public JSONHandler(DataSource dataSource) {
+        this.dataSource = dataSource;
+
+        Serializers.configureMapper(jsonMapper);
+        jsonMapper.registerModule(dataSource.getJacksonModule());
+    }
+
+    @Override
+    public void importData(File file) throws IOException {
+        Object data = jsonMapper.readValue(file, dataSource.getTargetClass());
+        dataSource.importData(data);
+    }
+
+    @Override
+    public void exportData(File file) throws IOException{
+        Object data = dataSource.exportData();
+        jsonMapper.writer(new Serializers.CustomPrettyPrinter())
+                .writeValue(file, data);
+    }
+}
+
+
diff --git a/src/main/java/design/persistence/importexport/XMLHandler.java b/src/main/java/design/persistence/importexport/XMLHandler.java
new file mode 100644
index 0000000..0a07d6e
--- /dev/null
+++ b/src/main/java/design/persistence/importexport/XMLHandler.java
@@ -0,0 +1,38 @@
+package design.persistence.importexport;
+import java.io.File;
+import java.io.IOException;
+import java.time.LocalDateTime;
+
+import com.fasterxml.jackson.databind.module.SimpleModule;
+import com.fasterxml.jackson.dataformat.xml.XmlMapper;
+import design.persistence.Serializers;
+
+public class XMLHandler implements DataHandler {
+
+    private final DataSource dataSource;
+    private final XmlMapper xmlMapper = new XmlMapper();
+
+    public XMLHandler(DataSource dataSource) {
+        this.dataSource = dataSource;
+
+        Serializers.configureMapper(xmlMapper);
+        SimpleModule module = dataSource.getJacksonModule();
+        module.addSerializer(LocalDateTime.class, new Serializers.DateTimeStringSerializer());
+        xmlMapper.registerModule(module);
+    }
+
+    @Override
+    public void importData(File file) throws IOException {
+        Object data = xmlMapper.readValue(file, dataSource.getTargetClass());
+        dataSource.importData(data);
+    }
+
+    @Override
+    public void exportData(File file) throws IOException {
+        Object data = dataSource.exportData();
+        xmlMapper.writerWithDefaultPrettyPrinter()
+                .writeValue(file, data);
+    }
+}
+
+
diff --git a/src/test/java/design/model/GolferTest.java b/src/test/java/design/model/GolferTest.java
index 5f113ab..98dad20 100644
--- a/src/test/java/design/model/GolferTest.java
+++ b/src/test/java/design/model/GolferTest.java
@@ -150,5 +150,4 @@ public class GolferTest {
     }
 
 
-}
-
+}
\ No newline at end of file
diff --git a/test.json b/test.json
new file mode 100644
index 0000000..4e42e0d
--- /dev/null
+++ b/test.json
@@ -0,0 +1,160 @@
+[
+  {
+    "clubs": [],
+    "nextClubId": 1,
+    "username": "test",
+    "passwordHash": 3556498,
+    "fullName": "test",
+    "courses": [],
+    "rounds": [],
+    "invites": []
+  },
+  {
+    "clubs": [],
+    "nextClubId": 1,
+    "username": "GUYHERE",
+    "passwordHash": 3556498,
+    "fullName": "GUYHERE",
+    "courses": [],
+    "rounds": [],
+    "invites": []
+  },
+  {
+    "clubs": [
+      {
+        "id": 1,
+        "manufacture": "Bobby",
+        "nickname": "swen 261",
+        "clubType": "DRIVER"
+      },
+      {
+        "id": 2,
+        "manufacture": "Bobby",
+        "nickname": "swen 262",
+        "clubType": "PUTTER"
+      },
+      {
+        "id": 3,
+        "manufacture": "sowclub",
+        "nickname": "man",
+        "clubType": "WOOD"
+      }
+    ],
+    "nextClubId": 4,
+    "username": "john_doe",
+    "passwordHash": 46792755,
+    "fullName": "John Doe",
+    "courses": [
+      2,
+      1
+    ],
+    "rounds": [
+      {
+        "course": 1,
+        "dateTime": [
+          2025,
+          10,
+          7,
+          13,
+          54,
+          37,
+          429963500
+        ],
+        "startingHole": {
+          "number": 1,
+          "par": 5
+        },
+        "plays": [
+          {
+            "holeNumber": 1,
+            "swings": [
+              {
+                "distance": 100,
+                "clubUsed": 1
+              },
+              {
+                "distance": 5,
+                "clubUsed": 2
+              },
+              {
+                "distance": 1,
+                "clubUsed": 2
+              }
+            ],
+            "swingCount": 3,
+            "distance": 106
+          },
+          {
+            "holeNumber": 2,
+            "swings": [
+              {
+                "distance": 1000,
+                "clubUsed": 1
+              },
+              {
+                "distance": 2,
+                "clubUsed": 1
+              }
+            ],
+            "swingCount": 2,
+            "distance": 1002
+          }
+        ],
+        "currentHoleIndex": 2,
+        "totalSwings": 5,
+        "totalDistance": 1108.0,
+        "currentHole": {
+          "number": 3,
+          "par": 4
+        }
+      },
+      {
+        "course": 1,
+        "dateTime": [
+          2025,
+          10,
+          8,
+          20,
+          19,
+          38,
+          968996400
+        ],
+        "startingHole": {
+          "number": 9,
+          "par": 3
+        },
+        "plays": [
+          {
+            "holeNumber": 9,
+            "swings": [
+              {
+                "distance": 204,
+                "clubUsed": 1
+              }
+            ],
+            "swingCount": 1,
+            "distance": 204
+          }
+        ],
+        "currentHoleIndex": 9,
+        "totalSwings": 1,
+        "totalDistance": 204.0,
+        "currentHole": {
+          "number": 10,
+          "par": 3
+        }
+      }
+    ],
+    "invites": []
+  },
+  {
+    "clubs": [],
+    "nextClubId": 1,
+    "username": "sowgro",
+    "passwordHash": -896456343,
+    "fullName": "sowgro",
+    "courses": [],
+    "rounds": [],
+    "invites": []
+  }
+]
\ No newline at end of file
diff --git a/test.xml b/test.xml
index 6a85537..4701977 100644
--- a/test.xml
+++ b/test.xml
@@ -1,127 +1,144 @@
-<export>
-  <items>
+<Golfers>
+  <item>
+    <clubs/>
     <nextClubId>1</nextClubId>
     <username>test</username>
     <passwordHash>3556498</passwordHash>
     <fullName>test</fullName>
-  </items>
-  <items>
+    <courses/>
+    <rounds/>
+    <invites/>
+  </item>
+  <item>
+    <clubs/>
     <nextClubId>1</nextClubId>
     <username>GUYHERE</username>
     <passwordHash>3556498</passwordHash>
     <fullName>GUYHERE</fullName>
-  </items>
-  <items>
+    <courses/>
+    <rounds/>
+    <invites/>
+  </item>
+  <item>
     <clubs>
-      <id>1</id>
-      <manufacture>Bobby</manufacture>
-      <nickname>swen 261</nickname>
-      <clubType>DRIVER</clubType>
-    </clubs>
-    <clubs>
-      <id>2</id>
-      <manufacture>Bobby</manufacture>
-      <nickname>swen 262</nickname>
-      <clubType>PUTTER</clubType>
-    </clubs>
-    <clubs>
-      <id>3</id>
-      <manufacture>sowclub</manufacture>
-      <nickname>man</nickname>
-      <clubType>WOOD</clubType>
+      <clubs>
+        <id>1</id>
+        <manufacture>Bobby</manufacture>
+        <nickname>swen 261</nickname>
+        <clubType>DRIVER</clubType>
+      </clubs>
+      <clubs>
+        <id>2</id>
+        <manufacture>Bobby</manufacture>
+        <nickname>swen 262</nickname>
+        <clubType>PUTTER</clubType>
+      </clubs>
+      <clubs>
+        <id>3</id>
+        <manufacture>sowclub</manufacture>
+        <nickname>man</nickname>
+        <clubType>WOOD</clubType>
+      </clubs>
     </clubs>
     <nextClubId>4</nextClubId>
     <username>john_doe</username>
     <passwordHash>46792755</passwordHash>
     <fullName>John Doe</fullName>
-    <courses>2</courses>
-    <courses>1</courses>
-    <rounds>
-      <course>1</course>
-      <dateTime>2025</dateTime>
-      <dateTime>10</dateTime>
-      <dateTime>7</dateTime>
-      <dateTime>13</dateTime>
-      <dateTime>54</dateTime>
-      <dateTime>37</dateTime>
-      <dateTime>429963500</dateTime>
-      <startingHole>
-        <number>1</number>
-        <par>5</par>
-      </startingHole>
-      <plays>
-        <holeNumber>1</holeNumber>
-        <swings>
-          <distance>100</distance>
-          <clubUsed>1</clubUsed>
-        </swings>
-        <swings>
-          <distance>5</distance>
-          <clubUsed>2</clubUsed>
-        </swings>
-        <swings>
-          <distance>1</distance>
-          <clubUsed>2</clubUsed>
-        </swings>
-        <swingCount>3</swingCount>
-        <distance>106</distance>
-      </plays>
-      <plays>
-        <holeNumber>2</holeNumber>
-        <swings>
-          <distance>1000</distance>
-          <clubUsed>1</clubUsed>
-        </swings>
-        <swings>
-          <distance>2</distance>
-          <clubUsed>1</clubUsed>
-        </swings>
-        <swingCount>2</swingCount>
-        <distance>1002</distance>
-      </plays>
-      <currentHoleIndex>2</currentHoleIndex>
-      <totalDistance>1108.0</totalDistance>
-      <currentHole>
-        <number>3</number>
-        <par>4</par>
-      </currentHole>
-      <totalSwings>5</totalSwings>
-    </rounds>
+    <courses>
+      <courses>2</courses>
+      <courses>1</courses>
+    </courses>
     <rounds>
-      <course>1</course>
-      <dateTime>2025</dateTime>
-      <dateTime>10</dateTime>
-      <dateTime>8</dateTime>
-      <dateTime>20</dateTime>
-      <dateTime>19</dateTime>
-      <dateTime>38</dateTime>
-      <dateTime>968996400</dateTime>
-      <startingHole>
-        <number>9</number>
-        <par>3</par>
-      </startingHole>
-      <plays>
-        <holeNumber>9</holeNumber>
-        <swings>
-          <distance>204</distance>
-          <clubUsed>1</clubUsed>
-        </swings>
-        <swingCount>1</swingCount>
-        <distance>204</distance>
-      </plays>
-      <currentHoleIndex>9</currentHoleIndex>
-      <totalDistance>204.0</totalDistance>
-      <currentHole>
-        <number>10</number>
-        <par>3</par>
-      </currentHole>
-      <totalSwings>1</totalSwings>
+      <rounds>
+        <course>1</course>
+        <dateTime>2025-10-07T13:54:37.429963500</dateTime>
+        <startingHole>
+          <number>1</number>
+          <par>5</par>
+        </startingHole>
+        <plays>
+          <plays>
+            <holeNumber>1</holeNumber>
+            <swings>
+              <swings>
+                <distance>100</distance>
+                <clubUsed>1</clubUsed>
+              </swings>
+              <swings>
+                <distance>5</distance>
+                <clubUsed>2</clubUsed>
+              </swings>
+              <swings>
+                <distance>1</distance>
+                <clubUsed>2</clubUsed>
+              </swings>
+            </swings>
+            <swingCount>3</swingCount>
+            <distance>106</distance>
+          </plays>
+          <plays>
+            <holeNumber>2</holeNumber>
+            <swings>
+              <swings>
+                <distance>1000</distance>
+                <clubUsed>1</clubUsed>
+              </swings>
+              <swings>
+                <distance>2</distance>
+                <clubUsed>1</clubUsed>
+              </swings>
+            </swings>
+            <swingCount>2</swingCount>
+            <distance>1002</distance>
+          </plays>
+        </plays>
+        <currentHoleIndex>2</currentHoleIndex>
+        <totalSwings>5</totalSwings>
+        <totalDistance>1108.0</totalDistance>
+        <currentHole>
+          <number>3</number>
+          <par>4</par>
+        </currentHole>
+      </rounds>
+      <rounds>
+        <course>1</course>
+        <dateTime>2025-10-08T20:19:38.968996400</dateTime>
+        <startingHole>
+          <number>9</number>
+          <par>3</par>
+        </startingHole>
+        <plays>
+          <plays>
+            <holeNumber>9</holeNumber>
+            <swings>
+              <swings>
+                <distance>204</distance>
+                <clubUsed>1</clubUsed>
+              </swings>
+            </swings>
+            <swingCount>1</swingCount>
+            <distance>204</distance>
+          </plays>
+        </plays>
+        <currentHoleIndex>9</currentHoleIndex>
+        <totalSwings>1</totalSwings>
+        <totalDistance>204.0</totalDistance>
+        <currentHole>
+          <number>10</number>
+          <par>3</par>
+        </currentHole>
+      </rounds>
     </rounds>
-  </items>
-  <items>
+    <invites/>
+  </item>
+  <item>
+    <clubs/>
     <nextClubId>1</nextClubId>
     <username>sowgro</username>
     <passwordHash>-896456343</passwordHash>
     <fullName>sowgro</fullName>
-  </items>
-</export>
+    <courses/>
+    <rounds/>
+    <invites/>
+  </item>
+</Golfers>