feat(util): add ReflectionUtil

lib/src/main/java/net/tomatentum/cutin/util/ReflectionUtil.java

@@ -4,16 +4,34 @@ import java.lang.annotation.Annotation;
 import java.lang.reflect.Method;
 import java.util.ArrayList;
 import java.util.Arrays;
+import java.util.Collection;
 import java.util.List;
+import java.util.Map;
 import java.util.Objects;
+import java.util.stream.Stream;
 
 public final class ReflectionUtil {
 
-    public static <T extends Annotation> boolean isAnnotationPresent(Method method, Class<T> annotationClass) {
-        if (method.isAnnotationPresent(annotationClass) || method.getDeclaringClass().isAnnotationPresent(annotationClass))
-            return true;
+    private ReflectionUtil() {}
 
-        return false;
+    private static final Map<Class<?>, Class<?>> PRIMITIVE_TO_BOXED = Map.ofEntries(
+            Map.entry(boolean.class, Boolean.class),
+            Map.entry(byte.class, Byte.class),
+            Map.entry(char.class, Character.class),
+            Map.entry(double.class, Double.class),
+            Map.entry(float.class, Float.class),
+            Map.entry(int.class, Integer.class),
+            Map.entry(long.class, Long.class),
+            Map.entry(short.class, Short.class),
+            Map.entry(void.class, Void.class)
+    );
+
+    public static Class<?> box(Class<?> type) {
+        return type.isPrimitive() ? PRIMITIVE_TO_BOXED.get(type) : type;
+    }
+
+    public static <T extends Annotation> boolean isAnnotationPresent(Method method, Class<T> annotationClass) {
+        return method.isAnnotationPresent(annotationClass) || method.getDeclaringClass().isAnnotationPresent(annotationClass);
     }
 
     public static <T extends Annotation> T getAnnotation(Method method, Class<T> annotationClass) {
@@ -22,6 +40,14 @@ public final class ReflectionUtil {
             method.getDeclaringClass().getAnnotation(annotationClass);
     }
 
+    public static Stream<Object> getReturnAsStream(Object ret) {
+        if (ret instanceof Object[] array)
+            return Stream.of(array);
+        if (ret instanceof Collection<?> coll)
+            return coll.stream().map(o -> (Object)o);
+        return Stream.of(ret);
+    }
+
     public static int getCastDepth(Class<?> child, Class<?> parent) {
 
         if (parent.equals(Object.class))
@@ -57,19 +83,20 @@ public final class ReflectionUtil {
             .filter(x -> isMethodCallable(x, parameters))
             .toList();
 
-        if (compatibleMethods.size() == 0)
+        if (compatibleMethods.isEmpty())
             throw new IllegalArgumentException("There are no compatible Methods provided");
 
+
         for (int i = 0; i < parameters.length; i++) {
             final int currI = i;
             Class<?>[] parameterTypes = compatibleMethods.stream()
-                .map(x -> x.getParameterTypes()[currI])
+                .map(x -> getBoxedParameterTypes(x)[currI])
                 .toArray(x -> new Class[x]);
 
             Class<?> mostSpecific = getMostSpecificClass(parameterTypes, parameters[i]);
 
             compatibleMethods = compatibleMethods.stream()
-                .filter(x -> Objects.equals(x.getParameterTypes()[currI], mostSpecific))
+                .filter(x -> Objects.equals(getBoxedParameterTypes(x)[currI], mostSpecific))
                 .toList();
         }
         
@@ -93,7 +120,7 @@ public final class ReflectionUtil {
         if (!Objects.equals(method.getParameterCount(), parameters.length))
             return false;
 
-        Class<?>[] methodParams = method.getParameterTypes();
+        Class<?>[] methodParams = getBoxedParameterTypes(method);
         for (int i = 0; i < parameters.length; i++) {
             if (!methodParams[i].isAssignableFrom(parameters[i]))
                 return false;
@@ -101,6 +128,12 @@ public final class ReflectionUtil {
         return true;
     }
 
+    public static Class<?>[] getBoxedParameterTypes(Method method) {
+        return Arrays.stream(method.getParameterTypes())
+            .map(ReflectionUtil::box)
+            .toArray(Class<?>[]::new);
+    }
+
     public static String getFullMethodName(Method method) {
         return method.getDeclaringClass().getName() + "." + method.getName();
     }