Enforce rawType to be a Class in ParameterizedTypeImpl

Enforce rawType to be a Class in ParameterizedTypeImpl

Author: panic08

gson/src/main/java/com/google/gson/internal/$Gson$Types.java

@@ -58,7 +58,7 @@ public final class $Gson$Types {
    */
   public static ParameterizedType newParameterizedTypeWithOwner(
       Type ownerType, Type rawType, Type... typeArguments) {
-    return new ParameterizedTypeImpl(ownerType, rawType, typeArguments);
+    return new ParameterizedTypeImpl(ownerType, (Class<?>) rawType, typeArguments);
   }
 
   /**
@@ -112,7 +112,7 @@ public static Type canonicalize(Type type) {
     } else if (type instanceof ParameterizedType) {
       ParameterizedType p = (ParameterizedType) type;
       return new ParameterizedTypeImpl(
-          p.getOwnerType(), p.getRawType(), p.getActualTypeArguments());
+          p.getOwnerType(), (Class<?>) p.getRawType(), p.getActualTypeArguments());
 
     } else if (type instanceof GenericArrayType) {
       GenericArrayType g = (GenericArrayType) type;
@@ -519,10 +519,9 @@ private static final class ParameterizedTypeImpl implements ParameterizedType, S
     @SuppressWarnings("serial")
     private final Type[] typeArguments;
 
-    public ParameterizedTypeImpl(Type ownerType, Type rawType, Type... typeArguments) {
-      // TODO: Should this enforce that rawType is a Class? See JDK implementation of
-      // the ParameterizedType interface and https://bugs.openjdk.org/browse/JDK-8250659
+    public ParameterizedTypeImpl(Type ownerType, Class<?> rawType, Type... typeArguments) {
       requireNonNull(rawType);
+
       if (ownerType == null && requiresOwnerType(rawType)) {
         throw new IllegalArgumentException("Must specify owner type for " + rawType);
       }

gson/src/main/java/com/google/gson/reflect/TypeToken.java

@@ -45,7 +45,7 @@
  *
  * <p>If the type arguments of the parameterized type are only available at runtime, for example
  * when you want to create a {@code List<E>} based on a {@code Class<E>} representing the element
- * type, the method {@link #getParameterized(Type, Type...)} can be used.
+ * type, the method {@link #getParameterized(Class, Type...)} can be used.
  *
  * @author Bob Lee
  * @author Sven Mawson
@@ -379,27 +379,20 @@ public static <T> TypeToken<T> get(Class<T> type) {
    * <p>If {@code rawType} is a non-generic class and no type arguments are provided, this method
    * simply delegates to {@link #get(Class)} and creates a {@code TypeToken(Class)}.
    *
-   * @throws IllegalArgumentException If {@code rawType} is not of type {@code Class}, or if the
+   * @throws IllegalArgumentException If the
    *     type arguments are invalid for the raw type
    */
-  public static TypeToken<?> getParameterized(Type rawType, Type... typeArguments) {
+  public static TypeToken<?> getParameterized(Class<?> rawType, Type... typeArguments) {
     Objects.requireNonNull(rawType);
     Objects.requireNonNull(typeArguments);
 
-    // Perform basic validation here because this is the only public API where users
-    // can create malformed parameterized types
-    if (!(rawType instanceof Class)) {
-      // See also https://bugs.openjdk.org/browse/JDK-8250659
-      throw new IllegalArgumentException("rawType must be of type Class, but was " + rawType);
-    }
-    Class<?> rawClass = (Class<?>) rawType;
-    TypeVariable<?>[] typeVariables = rawClass.getTypeParameters();
+    TypeVariable<?>[] typeVariables = rawType.getTypeParameters();
 
     int expectedArgsCount = typeVariables.length;
     int actualArgsCount = typeArguments.length;
     if (actualArgsCount != expectedArgsCount) {
       throw new IllegalArgumentException(
-          rawClass.getName()
+          rawType.getName()
               + " requires "
               + expectedArgsCount
               + " type arguments, but got "
@@ -408,14 +401,14 @@ public static TypeToken<?> getParameterized(Type rawType, Type... typeArguments)
 
     // For legacy reasons create a TypeToken(Class) if the type is not generic
     if (typeArguments.length == 0) {
-      return get(rawClass);
+      return get((Class<?>) rawType);
     }
 
     // Check for this here to avoid misleading exception thrown by ParameterizedTypeImpl
     if ($Gson$Types.requiresOwnerType(rawType)) {
       throw new IllegalArgumentException(
           "Raw type "
-              + rawClass.getName()
+              + ((Class<?>) rawType).getName()
               + " is not supported because it requires specifying an owner type");
     }
 

gson/src/test/java/com/google/gson/reflect/TypeTokenTest.java

@@ -186,16 +186,7 @@ public void testParameterizedFactory_Invalid() {
         NullPointerException.class,
         () -> TypeToken.getParameterized(List.class, new Type[] {null}));
 
-    GenericArrayType arrayType = (GenericArrayType) TypeToken.getArray(String.class).getType();
     IllegalArgumentException e =
-        assertThrows(
-            IllegalArgumentException.class,
-            () -> TypeToken.getParameterized(arrayType, new Type[0]));
-    assertThat(e)
-        .hasMessageThat()
-        .isEqualTo("rawType must be of type Class, but was java.lang.String[]");
-
-    e =
         assertThrows(
             IllegalArgumentException.class,
             () -> TypeToken.getParameterized(String.class, Number.class));