Reformat source code.

Change-Id: Id80213366bfddcaa10cf88af70cb07c15e62d34f
diff --git a/jgvariant-core/src/main/java/eu/mulk/jgvariant/core/Decoder.java b/jgvariant-core/src/main/java/eu/mulk/jgvariant/core/Decoder.java
index 2121cfb..60cef3e 100644
--- a/jgvariant-core/src/main/java/eu/mulk/jgvariant/core/Decoder.java
+++ b/jgvariant-core/src/main/java/eu/mulk/jgvariant/core/Decoder.java
@@ -4,14 +4,11 @@
 
 package eu.mulk.jgvariant.core;
 
-import static java.lang.Math.max;
-import static java.nio.ByteOrder.BIG_ENDIAN;
-import static java.nio.ByteOrder.LITTLE_ENDIAN;
-import static java.nio.charset.StandardCharsets.UTF_8;
-import static java.util.Objects.requireNonNullElse;
-import static java.util.stream.Collectors.toMap;
-
 import com.google.errorprone.annotations.Immutable;
+import org.apiguardian.api.API;
+import org.apiguardian.api.API.Status;
+import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
 
 import java.io.ByteArrayOutputStream;
 import java.io.IOException;
@@ -28,10 +25,11 @@
 import java.util.function.Predicate;
 import java.util.function.UnaryOperator;
 
-import org.apiguardian.api.API;
-import org.apiguardian.api.API.Status;
-import org.jetbrains.annotations.NotNull;
-import org.jetbrains.annotations.Nullable;
+import static java.lang.Math.max;
+import static java.nio.ByteOrder.BIG_ENDIAN;
+import static java.nio.ByteOrder.LITTLE_ENDIAN;
+import static java.nio.charset.StandardCharsets.UTF_8;
+import static java.util.Objects.requireNonNullElse;
 
 /**
  * Type class for decodable types.