feat: wrote EntityDeserializer

src/main/java/uulm/teamname/marvelous/gamelibrary/entities/Entity.java

@@ -1,10 +1,13 @@
 package uulm.teamname.marvelous.gamelibrary.entities;
 
+import com.fasterxml.jackson.databind.annotation.JsonDeserialize;
 import uulm.teamname.marvelous.gamelibrary.IntVector2;
+import uulm.teamname.marvelous.gamelibrary.json.ingame.EntityDeserializer;
 
 import java.util.Objects;
 
 /** Represents an abstract entity. */
+@JsonDeserialize(using = EntityDeserializer.class)
 public abstract class Entity {
     /** Whether or not the entity is currently active in the game */
     protected boolean active = true;

src/main/java/uulm/teamname/marvelous/gamelibrary/json/ingame/EntityDeserializer.java

@@ -0,0 +1,70 @@
+package uulm.teamname.marvelous.gamelibrary.json.ingame;
+
+import com.fasterxml.jackson.core.JsonParser;
+import com.fasterxml.jackson.core.JsonProcessingException;
+import com.fasterxml.jackson.core.ObjectCodec;
+import com.fasterxml.jackson.databind.DeserializationContext;
+import com.fasterxml.jackson.databind.JsonDeserializer;
+import com.fasterxml.jackson.databind.JsonNode;
+import com.fasterxml.jackson.databind.ObjectMapper;
+import uulm.teamname.marvelous.gamelibrary.IntVector2;
+import uulm.teamname.marvelous.gamelibrary.entities.*;
+import uulm.teamname.marvelous.gamelibrary.entities.Character;
+import uulm.teamname.marvelous.gamelibrary.json.JSON;
+
+import java.io.IOException;
+
+public class EntityDeserializer extends JsonDeserializer<Entity> {
+
+    private enum DeserializedEntityType {
+        Character,
+        Stone,
+        Rock
+    }
+
+    private final ObjectMapper mapper = new ObjectMapper();
+
+    @Override
+    public Entity deserialize(JsonParser p, DeserializationContext ctxt) throws IOException, JsonProcessingException {
+        ObjectCodec codec = p.getCodec();
+        JsonNode node = codec.readTree(p);
+
+        Entity result = null;
+
+        DeserializedEntityType type = DeserializedEntityType.valueOf(node.get("entityType").asText());
+
+        switch (type) {
+            case Character -> {
+                EntityID id = new EntityID(
+                        EntityType.valueOf("P" + node.get("PID").intValue()),
+                        node.get("ID").intValue());
+                result = new Character(
+                        id,
+                        mapper.readValue(node.get("position").toString(), IntVector2.class),
+                        node.get("name").asText(),
+                        node.get("HP").asInt(),
+                        node.get("MP").asInt(),
+                        node.get("AP").asInt(),
+                        -1,
+                        -1,
+                        -1
+                );
+            }
+            case Stone -> {
+                result = new InfinityStone(
+                        new EntityID(EntityType.InfinityStones, node.get("ID").asInt()),
+                        mapper.readValue(node.get("position").toString(), IntVector2.class),
+                        StoneType.valueOf(node.get("ID").asInt())
+                );
+            }
+            case Rock -> {
+                result = new Rock(
+                        new EntityID(EntityType.Rocks, node.get("ID").asInt()),
+                        mapper.readValue(node.get("position").toString(), IntVector2.class),
+                        node.get("HP").asInt()
+                );
+            }
+        }
+        return result;
+    }
+}

src/test/java/uulm/teamname/marvelous/gamelibrary/json/ingame/EntityDeserializerTest.java

@@ -0,0 +1,56 @@
+package uulm.teamname.marvelous.gamelibrary.json.ingame;
+
+import com.fasterxml.jackson.core.JsonProcessingException;
+import com.fasterxml.jackson.databind.ObjectMapper;
+import org.junit.jupiter.api.BeforeEach;
+import static org.assertj.core.api.Assertions.*;
+
+import org.junit.jupiter.api.Test;
+import uulm.teamname.marvelous.gamelibrary.IntVector2;
+import uulm.teamname.marvelous.gamelibrary.entities.Character;
+import uulm.teamname.marvelous.gamelibrary.entities.Entity;
+import uulm.teamname.marvelous.gamelibrary.entities.EntityID;
+import uulm.teamname.marvelous.gamelibrary.entities.EntityType;
+
+import static org.mockito.Mockito.*;
+import static org.junit.jupiter.api.Assertions.*;
+
+class EntityDeserializerTest {
+
+    ObjectMapper mapper;
+
+    @BeforeEach
+    void setUp() {
+        mapper = new ObjectMapper();
+    }
+
+    @Test
+    void simpleCharacterTest() throws JsonProcessingException {
+        var character = new Character(
+                new EntityID(EntityType.P1, 3),
+                new IntVector2(4, 2),
+                "God",
+                255,
+                65535,
+                4,
+                -1,
+                -1,
+                -1
+        );
+
+        var jsonRepresentingCharacter = """
+{
+    "entityType": "Character",
+    "name": "God",
+    "PID": 1,
+    "ID": 3,
+    "HP": 255,
+    "MP": 65535,
+    "AP": 4,
+    "position": [4, 2]
+}
+""";
+        assertThat(mapper.readValue(jsonRepresentingCharacter, Entity.class))
+                .isEqualTo(character);
+    }
+}