Implement basic serialization

3 files changed, 146 insertions, 3 deletions

diff --git a/src/main/java/design/persistence/CSVMasterDatabase.java b/src/main/java/design/persistence/CSVMasterDatabase.java
new file mode 100644
index 0000000..94ac470
--- /dev/null
+++ b/src/main/java/design/persistence/CSVMasterDatabase.java
@@ -0,0 +1,76 @@
+package design.persistence;
+
+import com.fasterxml.jackson.core.JsonParser;
+import com.fasterxml.jackson.databind.DeserializationContext;
+import com.fasterxml.jackson.databind.JsonDeserializer;
+import com.fasterxml.jackson.databind.MappingIterator;
+import com.fasterxml.jackson.databind.module.SimpleModule;
+import com.fasterxml.jackson.databind.node.ObjectNode;
+import com.fasterxml.jackson.dataformat.csv.CsvMapper;
+import com.fasterxml.jackson.dataformat.csv.CsvSchema;
+import design.model.Course;
+import design.model.Hole;
+
+import java.io.File;
+import java.io.IOException;
+import java.util.ArrayList;
+import java.util.List;
+
+public class CSVMasterDatabase implements MasterDatabase {
+
+    private final List<Course> cache;
+    private final CsvMapper mapper;
+    private final File file;
+
+    public CSVMasterDatabase(String filename) throws IOException {
+        this.cache = new ArrayList<>();
+        this.mapper = new CsvMapper();
+        this.file = new File(filename);
+
+        SimpleModule module = new SimpleModule();
+        module.addDeserializer(Course.class, new CourseDeserializer());
+        mapper.registerModule(module);
+
+        load();
+    }
+
+    public void load() throws IOException {
+        MappingIterator<Course> it = mapper
+                .readerFor(Course.class)
+                .with(CsvSchema.emptySchema().withHeader())
+                .readValues(file);
+
+        cache.addAll(it.readAll());
+    }
+
+    @Override
+    public Course[] getCourses() {
+        return cache.toArray(Course[]::new);
+    }
+
+    @Override
+    public Course getCourse(String name) {
+        return null;
+    }
+
+    private static class CourseDeserializer extends JsonDeserializer<Course> {
+        @Override
+        public Course deserialize(JsonParser p, DeserializationContext ctxt) throws IOException {
+            ObjectNode node = p.getCodec().readTree(p);
+
+            String name = node.get("Course Name").asText();
+            double difficulty = node.get("Difficulty Rating").asDouble();
+            String location = node.get("Location").asText();
+            int holes = node.get("Number of Holes").asInt();
+            int totalPar = node.get("Total Par").asInt();
+
+            String[] parValues = node.get("Par Per Hole").asText().split(";");
+            List<Hole> holeList = new ArrayList<>();
+            for (int i = 0; i < parValues.length; i++) {
+                holeList.add(new Hole(i + 1, Integer.parseInt(parValues[i].trim())));
+            }
+
+            return new Course(name, (int) difficulty, location, holes, totalPar, holeList);
+        }
+    }
+}
diff --git a/src/main/java/design/persistence/JSONPersonalDatabase.java b/src/main/java/design/persistence/JSONPersonalDatabase.java
new file mode 100644
index 0000000..3ec0012
--- /dev/null
+++ b/src/main/java/design/persistence/JSONPersonalDatabase.java
@@ -0,0 +1,65 @@
+package design.persistence;
+
+import com.fasterxml.jackson.databind.ObjectMapper;
+import design.model.Golfer;
+
+import java.io.File;
+import java.io.IOException;
+import java.util.HashMap;
+import java.util.Map;
+
+public class JSONPersonalDatabase implements PersonalDatabase {
+
+    private final Map<String, Golfer> cache;
+    private final ObjectMapper mapper;
+    private final File file;
+
+    public JSONPersonalDatabase(String filename) throws IOException {
+        this.file = new File(filename);
+        this.cache = new HashMap<>();
+        this.mapper = new ObjectMapper();
+
+        load();
+    }
+
+    private void load() throws IOException {
+        Golfer[] data = mapper.readValue(file, Golfer[].class);
+        cache.clear();
+        for (Golfer i : data) {
+            cache.put(i.getUsername(), i);
+        }
+    }
+
+    private void save() throws IOException {
+        Golfer[] data = cache.values().toArray(Golfer[]::new);
+        mapper.writeValue(file, data);
+    }
+
+    @Override
+    public Golfer[] getGolfers() {
+        return new Golfer[0];
+    }
+
+    @Override
+    public Golfer getGolfer(String username) {
+        return cache.get(username);
+    }
+
+    @Override
+    public void addGolfer(Golfer golfer) throws IOException {
+        cache.put(golfer.getUsername(), golfer);
+        save();
+    }
+
+    @Override
+    public void removeGolfer(Golfer golfer) throws IOException {
+        cache.remove(golfer.getUsername());
+        save();
+    }
+
+    @Override
+    public void updateGolfer(Golfer golfer) throws IOException {
+        cache.put(golfer.getUsername(), golfer);
+        save();
+    }
+}
diff --git a/src/main/java/design/persistence/PersonalDatabase.java b/src/main/java/design/persistence/PersonalDatabase.java
index e1023cf..783e982 100644
--- a/src/main/java/design/persistence/PersonalDatabase.java
+++ b/src/main/java/design/persistence/PersonalDatabase.java
@@ -2,10 +2,12 @@ package design.persistence;
 
 import design.model.Golfer;
 
+import java.io.IOException;
+
 public interface PersonalDatabase {
     Golfer[] getGolfers();
     Golfer getGolfer(String name);
-    void addGolfer(Golfer golfer);
-    void removeGolfer(Golfer golfer);
-    void updateGolfer(Golfer golfer);
+    void addGolfer(Golfer golfer) throws IOException;
+    void removeGolfer(Golfer golfer) throws IOException;
+    void updateGolfer(Golfer golfer) throws IOException;
 }