@Test
public void testGetTypeArguments() {
Map<TypeVariable<?>, Type> typeVarAssigns;
TypeVariable<?> treeSetTypeVar;
Type typeArg;
typeVarAssigns = TypeUtils.getTypeArguments(Integer.class, Comparable.class);
treeSetTypeVar = Comparable.class.getTypeParameters()[0];
Assert.assertTrue(
"Type var assigns for Comparable from Integer: " + typeVarAssigns,
typeVarAssigns.containsKey(treeSetTypeVar));
typeArg = typeVarAssigns.get(treeSetTypeVar);
Assert.assertEquals(
"Type argument of Comparable from Integer: " + typeArg,
Integer.class,
typeVarAssigns.get(treeSetTypeVar));
typeVarAssigns = TypeUtils.getTypeArguments(int.class, Comparable.class);
treeSetTypeVar = Comparable.class.getTypeParameters()[0];
Assert.assertTrue(
"Type var assigns for Comparable from int: " + typeVarAssigns,
typeVarAssigns.containsKey(treeSetTypeVar));
typeArg = typeVarAssigns.get(treeSetTypeVar);
Assert.assertEquals(
"Type argument of Comparable from int: " + typeArg,
Integer.class,
typeVarAssigns.get(treeSetTypeVar));
final Collection<Integer> col = Arrays.asList(new Integer[0]);
typeVarAssigns = TypeUtils.getTypeArguments(List.class, Collection.class);
treeSetTypeVar = Comparable.class.getTypeParameters()[0];
Assert.assertFalse(
"Type var assigns for Collection from List: " + typeVarAssigns,
typeVarAssigns.containsKey(treeSetTypeVar));
typeVarAssigns = TypeUtils.getTypeArguments(AAAClass.BBBClass.class, AAClass.BBClass.class);
Assert.assertTrue(typeVarAssigns.size() == 2);
Assert.assertEquals(String.class, typeVarAssigns.get(AAClass.class.getTypeParameters()[0]));
Assert.assertEquals(
String.class, typeVarAssigns.get(AAClass.BBClass.class.getTypeParameters()[0]));
typeVarAssigns = TypeUtils.getTypeArguments(Other.class, This.class);
Assert.assertEquals(2, typeVarAssigns.size());
Assert.assertEquals(String.class, typeVarAssigns.get(This.class.getTypeParameters()[0]));
Assert.assertEquals(
Other.class.getTypeParameters()[0], typeVarAssigns.get(This.class.getTypeParameters()[1]));
typeVarAssigns = TypeUtils.getTypeArguments(And.class, This.class);
Assert.assertEquals(2, typeVarAssigns.size());
Assert.assertEquals(Number.class, typeVarAssigns.get(This.class.getTypeParameters()[0]));
Assert.assertEquals(Number.class, typeVarAssigns.get(This.class.getTypeParameters()[1]));
typeVarAssigns = TypeUtils.getTypeArguments(Thing.class, Other.class);
Assert.assertEquals(2, typeVarAssigns.size());
Assert.assertEquals(
getClass().getTypeParameters()[0], typeVarAssigns.get(getClass().getTypeParameters()[0]));
Assert.assertEquals(
getClass().getTypeParameters()[0], typeVarAssigns.get(Other.class.getTypeParameters()[0]));
}
/** The default constructor. */
protected TypeLiteral() {
this.value =
Validate.notNull(
TypeUtils.getTypeArguments(getClass(), TypeLiteral.class).get(T),
"%s does not assign type parameter %s",
getClass(),
TypeUtils.toLongString(T));
this.toString =
String.format("%s<%s>", TypeLiteral.class.getSimpleName(), TypeUtils.toString(value));
}
/**
* Get the type that is provided by a given implementation of {@link Provider}.
*
* @param providerClass The provider's class
* @return The provided class type
* @throws IllegalArgumentException if the class doesn't actually implement Provider
*/
public static Class<?> getProvidedType(Class<? extends Provider<?>> providerClass) {
com.google.common.base.Preconditions.checkArgument(
Provider.class.isAssignableFrom(providerClass), "class is not Provider class");
Map<TypeVariable<?>, Type> bindings = TypeUtils.getTypeArguments(providerClass, Provider.class);
if (!bindings.containsKey(PROVIDER_TYPE_VAR)) {
throw new IllegalArgumentException(
"Class provided by " + providerClass.getName() + " is generic");
}
final Class<?> inferredType = TypeUtils.getRawType(bindings.get(PROVIDER_TYPE_VAR), null);
try {
final Class<?> observedType = providerClass.getMethod("get").getReturnType();
if (inferredType != null && inferredType.isAssignableFrom(observedType)) {
return observedType;
} else {
return inferredType;
}
} catch (NoSuchMethodException e) {
throw new IllegalArgumentException("Class does not implement get()");
}
}
@Override
public boolean supports(TherianContext context, Add<?, ? extends Collection<?>> add) {
// cannot add to immutable types
if (context.eval(ImmutableCheck.of(add.getTargetPosition())).booleanValue()) {
return false;
}
if (!TypeUtils.isAssignable(add.getTargetPosition().getType(), Collection.class)) {
return false;
}
final Type targetElementType =
TypeUtils.unrollVariables(
TypeUtils.getTypeArguments(add.getTargetPosition().getType(), Collection.class),
Collection.class.getTypeParameters()[0]);
if (targetElementType == null) {
// raw collection
return true;
}
return TypeUtils.isAssignable(add.getSourcePosition().getType(), targetElementType);
}