Initial tag commit

src/main/java/net/minestom/server/tag/Tag.java

@@ -0,0 +1,110 @@
+package net.minestom.server.tag;
+
+import org.jetbrains.annotations.NotNull;
+import org.jglrxavpok.hephaistos.nbt.NBT;
+import org.jglrxavpok.hephaistos.nbt.NBTCompound;
+
+import java.util.function.BiConsumer;
+import java.util.function.Function;
+
+public class Tag<T> {
+
+    private final String key;
+    private final Function<NBTCompound, T> readFunction;
+    private final BiConsumer<NBTCompound, T> writeConsumer;
+
+    private Tag(@NotNull String key,
+                @NotNull Function<NBTCompound, T> readFunction,
+                @NotNull BiConsumer<NBTCompound, T> writeConsumer) {
+        this.key = key;
+        this.readFunction = readFunction;
+        this.writeConsumer = writeConsumer;
+    }
+
+    public @NotNull String getKey() {
+        return key;
+    }
+
+    protected T read(@NotNull NBTCompound nbtCompound) {
+        return readFunction.apply(nbtCompound);
+    }
+
+    protected void write(@NotNull NBTCompound nbtCompound, @NotNull T value) {
+        this.writeConsumer.accept(nbtCompound, value);
+    }
+
+    public static @NotNull Tag<Byte> Byte(@NotNull String key) {
+        return new Tag<>(key,
+                nbtCompound -> nbtCompound.getByte(key),
+                (nbtCompound, value) -> nbtCompound.setByte(key, value));
+    }
+
+    public static @NotNull Tag<Short> Short(@NotNull String key) {
+        return new Tag<>(key,
+                nbtCompound -> nbtCompound.getShort(key),
+                (nbtCompound, value) -> nbtCompound.setShort(key, value));
+    }
+
+    public static @NotNull Tag<Integer> Integer(@NotNull String key) {
+        return new Tag<>(key,
+                nbtCompound -> nbtCompound.getInt(key),
+                (nbtCompound, integer) -> nbtCompound.setInt(key, integer));
+    }
+
+    public static @NotNull Tag<Long> Long(@NotNull String key) {
+        return new Tag<>(key,
+                nbtCompound -> nbtCompound.getLong(key),
+                (nbtCompound, value) -> nbtCompound.setLong(key, value));
+    }
+
+    public static @NotNull Tag<Float> Float(@NotNull String key) {
+        return new Tag<>(key,
+                nbtCompound -> nbtCompound.getFloat(key),
+                (nbtCompound, value) -> nbtCompound.setFloat(key, value));
+    }
+
+    public static @NotNull Tag<Double> Double(@NotNull String key) {
+        return new Tag<>(key,
+                nbtCompound -> nbtCompound.getDouble(key),
+                (nbtCompound, value) -> nbtCompound.setDouble(key, value));
+    }
+
+    public static @NotNull Tag<byte[]> ByteArray(@NotNull String key) {
+        return new Tag<>(key,
+                nbtCompound -> nbtCompound.getByteArray(key),
+                (nbtCompound, value) -> nbtCompound.setByteArray(key, value));
+    }
+
+    public static @NotNull Tag<String> String(@NotNull String key) {
+        return new Tag<>(key,
+                nbtCompound -> nbtCompound.getString(key),
+                (nbtCompound, value) -> nbtCompound.setString(key, value));
+    }
+
+    public static @NotNull Tag<NBT> NBT(@NotNull String key) {
+        return new Tag<>(key,
+                nbt -> {
+                    var currentNBT = nbt.get(key);
+
+                    // Avoid a NPE when cloning a null variable.
+                    if (currentNBT == null) {
+                        return null;
+                    }
+
+                    return currentNBT.deepClone();
+                },
+                ((nbt, value) -> nbt.set(key, value.deepClone())));
+    }
+
+    public static @NotNull Tag<int[]> IntArray(@NotNull String key) {
+        return new Tag<>(key,
+                nbtCompound -> nbtCompound.getIntArray(key),
+                (nbtCompound, value) -> nbtCompound.setIntArray(key, value));
+    }
+
+    public static @NotNull Tag<long[]> LongArray(@NotNull String key) {
+        return new Tag<>(key,
+                nbtCompound -> nbtCompound.getLongArray(key),
+                (nbtCompound, value) -> nbtCompound.setLongArray(key, value));
+    }
+}

src/main/java/net/minestom/server/tag/TagGetter.java

@@ -0,0 +1,8 @@
+package net.minestom.server.tag;
+
+import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
+
+public interface TagGetter {
+    <T> @Nullable T getTag(@NotNull Tag<T> tag);
+}

src/main/java/net/minestom/server/tag/TagSetter.java

@@ -0,0 +1,8 @@
+package net.minestom.server.tag;
+
+import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
+
+public interface TagSetter {
+    <T> void setTag(@NotNull Tag<T> tag, @Nullable T value);
+}