merged from main

1 files changed, 83 insertions, 0 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..fe89191
--- /dev/null
+++ b/src/main/java/design/persistence/CSVMasterDatabase.java
@@ -0,0 +1,83 @@
+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) {
+        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);
+
+        try {
+            load();
+        } catch (IOException ex) {
+            throw new RuntimeException(ex);
+        }
+    }
+
+    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(int id) {
+        return cache.get(id);
+    }
+
+    private static class CourseDeserializer extends JsonDeserializer<Course> {
+        int curID = 0;
+
+        @Override
+        public Course deserialize(JsonParser p, DeserializationContext ctxt) throws IOException {
+            ObjectNode node = p.getCodec().readTree(p);
+
+            int id = curID++;
+            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(id, name, (int) difficulty, location, holes, totalPar, holeList);
+        }
+    }
+}