1 files changed, 125 insertions, 0 deletions
diff --git a/src/main/java/seu/se/Exercise.java b/src/main/java/seu/se/Exercise.java
new file mode 100644
index 0000000..6df9212
--- /dev/null
+++ b/src/main/java/seu/se/Exercise.java
@@ -0,0 +1,125 @@
+package seu.se;
+
+import com.fasterxml.jackson.annotation.JsonCreator;
+import com.fasterxml.jackson.annotation.JsonProperty;
+import com.fasterxml.jackson.core.JsonGenerator;
+import com.fasterxml.jackson.databind.SerializerProvider;
+import com.fasterxml.jackson.databind.annotation.JsonSerialize;
+import com.fasterxml.jackson.databind.ser.std.StdSerializer;
+
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.data.annotation.PersistenceCreator;
+import org.springframework.data.neo4j.core.schema.Id;
+import org.springframework.data.neo4j.core.schema.Node;
+
+import java.io.IOException;
+import java.util.LinkedList;
+import java.util.List;
+import java.util.Map;
+
+@Node
+public class Exercise {
+    @Id
+    private String questionId;
+    private String question;
+    private List<OptionPair> options;
+    private String answer;
+
+    public interface Choice {
+        String A = "A";
+        String B = "B";
+        String C = "C";
+        String D = "D";
+    }
+
+    @Node
+    @JsonSerialize(using = OptionPair.OptionPairSerializer.class)
+    public static class OptionPair {
+        @Id
+        private final String id;
+        private final String key;
+        private final String value;
+
+        public static class OptionPairSerializer extends StdSerializer<OptionPair> {
+            public OptionPairSerializer() {
+                this(null);
+            }
+
+            public OptionPairSerializer(Class<OptionPair> t) {
+                super(t);
+            }
+
+            @Override
+            public void serialize(OptionPair value, JsonGenerator gen, SerializerProvider provider) throws IOException {
+                gen.writeStartObject();
+                gen.writeStringField(value.key, value.value);
+                gen.writeEndObject();
+            }
+        }
+
+        public OptionPair(String id, String key, String value) {
+            this.id = id;
+            this.key = key;
+            this.value = value;
+        }
+
+        public String value() {
+            return value;
+        }
+
+        public String key() {
+            return key;
+        }
+
+        public String getId() {
+            return id;
+        }
+    }
+
+    @JsonCreator
+    public Exercise(@JsonProperty("questionId") String questionId, @JsonProperty("question") String question, @JsonProperty("options") Map<String, String> options, @JsonProperty("answer") String answer) {
+        this.questionId = questionId;
+        this.question = question;
+        this.options = new LinkedList<OptionPair>();
+        options.forEach((k, v) -> this.options.add(new OptionPair(String.format("%s.%s", questionId, k), k, v)));
+        this.answer = answer;
+    }
+
+    @Autowired
+    @PersistenceCreator
+    // https://stackoverflow.com/questions/55827640/how-to-fix-failed-to-instantiate-classname-using-constructor-no-constructor
+    public Exercise(String questionId, String question, List<OptionPair> options, String answer) {
+        this.questionId = questionId;
+        this.question = question;
+        this.options = options;
+        this.answer = answer;
+    }
+
+    public String getQuestion() {
+        return question;
+    }
+
+    public void setQuestion(String question) {
+        this.question = question;
+    }
+
+    public String getQuestionId() {
+        return questionId;
+    }
+
+    public List<OptionPair> getOptions() {
+        return options;
+    }
+
+    public void setOptions(List<OptionPair> options) {
+        this.options = options;
+    }
+
+    public String getAnswer() {
+        return answer;
+    }
+
+    public void setAnswer(String answer) {
+        this.answer = answer;
+    }
+}