com.google.inject.throwingproviders.CheckedProvideUtils Maven / Gradle / Ivy
/*
* Copyright (C) 2012 Google Inc.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package com.google.inject.throwingproviders;
import com.google.inject.Binder;
import com.google.inject.TypeLiteral;
import com.google.inject.internal.Annotations;
import com.google.inject.internal.Errors;
import com.google.inject.spi.Message;
import java.lang.annotation.Annotation;
import java.lang.reflect.AnnotatedElement;
import java.lang.reflect.Constructor;
/**
* Utilities for the throwing provider module.
*
* @author [email protected] (Sam Berlin)
*/
class CheckedProvideUtils {
private CheckedProvideUtils() {}
private static final String CONSTRUCTOR_RULES =
"Classes must have either one (and only one) constructor annotated with @ThrowingInject.";
@SuppressWarnings("unchecked") // safe because it's a constructor of the typeLiteral
static Constructor findThrowingConstructor(
TypeLiteral typeLiteral, Binder binder) {
Class rawType = typeLiteral.getRawType();
Errors errors = new Errors(rawType);
Constructor cxtor = null;
for (Constructor constructor : rawType.getDeclaredConstructors()) {
if (constructor.isAnnotationPresent(ThrowingInject.class)) {
if (cxtor != null) {
errors.addMessage(
"%s has more than one constructor annotated with @ThrowingInject. "
+ CONSTRUCTOR_RULES,
rawType);
}
cxtor = constructor;
Annotation misplacedBindingAnnotation =
Annotations.findBindingAnnotation(
errors, cxtor, ((AnnotatedElement) cxtor).getAnnotations());
if (misplacedBindingAnnotation != null) {
errors.misplacedBindingAnnotation(cxtor, misplacedBindingAnnotation);
}
}
}
if (cxtor == null) {
errors.addMessage(
"Could not find a suitable constructor in %s. " + CONSTRUCTOR_RULES, rawType);
}
for (Message msg : errors.getMessages()) {
binder.addError(msg);
}
return (Constructor) cxtor;
}
/** Adds errors to the binder if the exceptions aren't valid. */
static void validateExceptions(
Binder binder,
Iterable> actualExceptionTypes,
Iterable> expectedExceptionTypes,
Class checkedProvider) {
// Validate the exceptions in the method match the exceptions
// in the CheckedProvider.
for (TypeLiteral exType : actualExceptionTypes) {
Class exActual = exType.getRawType();
// Ignore runtime exceptions & errors.
if (RuntimeException.class.isAssignableFrom(exActual)
|| Error.class.isAssignableFrom(exActual)) {
continue;
}
boolean notAssignable = true;
for (Class exExpected : expectedExceptionTypes) {
if (exExpected.isAssignableFrom(exActual)) {
notAssignable = false;
break;
}
}
if (notAssignable) {
binder.addError(
"%s is not compatible with the exceptions (%s) declared in "
+ "the CheckedProvider interface (%s)",
exActual, expectedExceptionTypes, checkedProvider);
}
}
}
}