/* * Copyright (C) 2006 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 org.elasticsearch.common.inject.internal; import org.apache.lucene.util.CollectionUtil; import org.elasticsearch.common.inject.ConfigurationException; import org.elasticsearch.common.inject.CreationException; import org.elasticsearch.common.inject.Key; import org.elasticsearch.common.inject.MembersInjector; import org.elasticsearch.common.inject.Provider; import org.elasticsearch.common.inject.ProvisionException; import org.elasticsearch.common.inject.Scope; import org.elasticsearch.common.inject.TypeLiteral; import org.elasticsearch.common.inject.spi.Dependency; import org.elasticsearch.common.inject.spi.InjectionListener; import org.elasticsearch.common.inject.spi.InjectionPoint; import org.elasticsearch.common.inject.spi.Message; import org.elasticsearch.common.inject.spi.TypeListenerBinding; import java.io.PrintWriter; import java.io.StringWriter; import java.lang.annotation.Annotation; import java.lang.reflect.Constructor; import java.lang.reflect.Field; import java.lang.reflect.Member; import java.lang.reflect.Type; import java.util.ArrayList; import java.util.Arrays; import java.util.Collection; import java.util.Collections; import java.util.Comparator; import java.util.Formatter; import java.util.List; import java.util.Locale; import static java.util.Collections.emptySet; import static java.util.Collections.unmodifiableList; /** * A collection of error messages. If this type is passed as a method parameter, the method is * considered to have executed successfully only if new errors were not added to this collection. * <p> * Errors can be chained to provide additional context. To add context, call {@link #withSource} * to create a new Errors instance that contains additional context. All messages added to the * returned instance will contain full context. * <p> * To avoid messages with redundant context, {@link #withSource} should be added sparingly. A * good rule of thumb is to assume a method's caller has already specified enough context to * identify that method. When calling a method that's defined in a different context, call that * method with an errors object that includes its context. * * @author jessewilson@google.com (Jesse Wilson) */ public final class Errors { /** * The root errors object. Used to access the list of error messages. */ private final Errors root; /** * The parent errors object. Used to obtain the chain of source objects. */ private final Errors parent; /** * The leaf source for errors added here. */ private final Object source; /** * null unless (root == this) and error messages exist. Never an empty list. */ private List<Message> errors; // lazy, use getErrorsForAdd() public Errors() { this.root = this; this.parent = null; this.source = SourceProvider.UNKNOWN_SOURCE; } public Errors(Object source) { this.root = this; this.parent = null; this.source = source; } private Errors(Errors parent, Object source) { this.root = parent.root; this.parent = parent; this.source = source; } /** * Returns an instance that uses {@code source} as a reference point for newly added errors. */ public Errors withSource(Object source) { return source == SourceProvider.UNKNOWN_SOURCE ? this : new Errors(this, source); } /** * We use a fairly generic error message here. The motivation is to share the * same message for both bind time errors: * <pre><code>Guice.createInjector(new AbstractModule() { * public void configure() { * bind(Runnable.class); * } * }</code></pre> * ...and at provide-time errors: * <pre><code>Guice.createInjector().getInstance(Runnable.class);</code></pre> * Otherwise we need to know who's calling when resolving a just-in-time * binding, which makes things unnecessarily complex. */ public Errors missingImplementation(Key key) { return addMessage("No implementation for %s was bound.", key); } public Errors converterReturnedNull(String stringValue, Object source, TypeLiteral<?> type, MatcherAndConverter matchingConverter) { return addMessage("Received null converting '%s' (bound at %s) to %s%n" + " using %s.", stringValue, convert(source), type, matchingConverter); } public Errors conversionTypeError(String stringValue, Object source, TypeLiteral<?> type, MatcherAndConverter matchingConverter, Object converted) { return addMessage("Type mismatch converting '%s' (bound at %s) to %s%n" + " using %s.%n" + " Converter returned %s.", stringValue, convert(source), type, matchingConverter, converted); } public Errors conversionError(String stringValue, Object source, TypeLiteral<?> type, MatcherAndConverter matchingConverter, RuntimeException cause) { return errorInUserCode(cause, "Error converting '%s' (bound at %s) to %s%n" + " using %s.%n" + " Reason: %s", stringValue, convert(source), type, matchingConverter, cause); } public Errors ambiguousTypeConversion(String stringValue, Object source, TypeLiteral<?> type, MatcherAndConverter a, MatcherAndConverter b) { return addMessage("Multiple converters can convert '%s' (bound at %s) to %s:%n" + " %s and%n" + " %s.%n" + " Please adjust your type converter configuration to avoid overlapping matches.", stringValue, convert(source), type, a, b); } public Errors bindingToProvider() { return addMessage("Binding to Provider is not allowed."); } public Errors subtypeNotProvided(Class<? extends Provider<?>> providerType, Class<?> type) { return addMessage("%s doesn't provide instances of %s.", providerType, type); } public Errors notASubtype(Class<?> implementationType, Class<?> type) { return addMessage("%s doesn't extend %s.", implementationType, type); } public Errors recursiveImplementationType() { return addMessage("@ImplementedBy points to the same class it annotates."); } public Errors recursiveProviderType() { return addMessage("@ProvidedBy points to the same class it annotates."); } public Errors missingRuntimeRetention(Object source) { return addMessage("Please annotate with @Retention(RUNTIME).%n" + " Bound at %s.", convert(source)); } public Errors missingScopeAnnotation() { return addMessage("Please annotate with @ScopeAnnotation."); } public Errors optionalConstructor(Constructor constructor) { return addMessage("%s is annotated @Inject(optional=true), " + "but constructors cannot be optional.", constructor); } public Errors cannotBindToGuiceType(String simpleName) { return addMessage("Binding to core guice framework type is not allowed: %s.", simpleName); } public Errors scopeNotFound(Class<? extends Annotation> scopeAnnotation) { return addMessage("No scope is bound to %s.", scopeAnnotation); } public Errors scopeAnnotationOnAbstractType( Class<? extends Annotation> scopeAnnotation, Class<?> type, Object source) { return addMessage("%s is annotated with %s, but scope annotations are not supported " + "for abstract types.%n Bound at %s.", type, scopeAnnotation, convert(source)); } public Errors misplacedBindingAnnotation(Member member, Annotation bindingAnnotation) { return addMessage("%s is annotated with %s, but binding annotations should be applied " + "to its parameters instead.", member, bindingAnnotation); } private static final String CONSTRUCTOR_RULES = "Classes must have either one (and only one) constructor " + "annotated with @Inject or a zero-argument constructor that is not private."; public Errors missingConstructor(Class<?> implementation) { return addMessage("Could not find a suitable constructor in %s. " + CONSTRUCTOR_RULES, implementation); } public Errors tooManyConstructors(Class<?> implementation) { return addMessage("%s has more than one constructor annotated with @Inject. " + CONSTRUCTOR_RULES, implementation); } public Errors duplicateScopes(Scope existing, Class<? extends Annotation> annotationType, Scope scope) { return addMessage("Scope %s is already bound to %s. Cannot bind %s.", existing, annotationType, scope); } public Errors voidProviderMethod() { return addMessage("Provider methods must return a value. Do not return void."); } public Errors missingConstantValues() { return addMessage("Missing constant value. Please call to(...)."); } public Errors cannotInjectInnerClass(Class<?> type) { return addMessage("Injecting into inner classes is not supported. " + "Please use a 'static' class (top-level or nested) instead of %s.", type); } public Errors duplicateBindingAnnotations(Member member, Class<? extends Annotation> a, Class<? extends Annotation> b) { return addMessage("%s has more than one annotation annotated with @BindingAnnotation: " + "%s and %s", member, a, b); } public Errors duplicateScopeAnnotations( Class<? extends Annotation> a, Class<? extends Annotation> b) { return addMessage("More than one scope annotation was found: %s and %s.", a, b); } public Errors recursiveBinding() { return addMessage("Binding points to itself."); } public Errors bindingAlreadySet(Key<?> key, Object source) { return addMessage("A binding to %s was already configured at %s.", key, convert(source)); } public Errors childBindingAlreadySet(Key<?> key) { return addMessage("A binding to %s already exists on a child injector.", key); } public Errors errorInjectingMethod(Throwable cause) { return errorInUserCode(cause, "Error injecting method, %s", cause); } public Errors errorNotifyingTypeListener(TypeListenerBinding listener, TypeLiteral<?> type, Throwable cause) { return errorInUserCode(cause, "Error notifying TypeListener %s (bound at %s) of %s.%n" + " Reason: %s", listener.getListener(), convert(listener.getSource()), type, cause); } public Errors errorInjectingConstructor(Throwable cause) { return errorInUserCode(cause, "Error injecting constructor, %s", cause); } public Errors errorInProvider(RuntimeException runtimeException) { return errorInUserCode(runtimeException, "Error in custom provider, %s", runtimeException); } public Errors errorInUserInjector( MembersInjector<?> listener, TypeLiteral<?> type, RuntimeException cause) { return errorInUserCode(cause, "Error injecting %s using %s.%n" + " Reason: %s", type, listener, cause); } public Errors errorNotifyingInjectionListener( InjectionListener<?> listener, TypeLiteral<?> type, RuntimeException cause) { return errorInUserCode(cause, "Error notifying InjectionListener %s of %s.%n" + " Reason: %s", listener, type, cause); } public void exposedButNotBound(Key<?> key) { addMessage("Could not expose() %s, it must be explicitly bound.", key); } public static Collection<Message> getMessagesFromThrowable(Throwable throwable) { if (throwable instanceof ProvisionException) { return ((ProvisionException) throwable).getErrorMessages(); } else if (throwable instanceof ConfigurationException) { return ((ConfigurationException) throwable).getErrorMessages(); } else if (throwable instanceof CreationException) { return ((CreationException) throwable).getErrorMessages(); } else { return emptySet(); } } public Errors errorInUserCode(Throwable cause, String messageFormat, Object... arguments) { Collection<Message> messages = getMessagesFromThrowable(cause); if (!messages.isEmpty()) { return merge(messages); } else { return addMessage(cause, messageFormat, arguments); } } public Errors cannotInjectRawProvider() { return addMessage("Cannot inject a Provider that has no type parameter"); } public Errors cannotInjectRawMembersInjector() { return addMessage("Cannot inject a MembersInjector that has no type parameter"); } public Errors cannotInjectTypeLiteralOf(Type unsupportedType) { return addMessage("Cannot inject a TypeLiteral of %s", unsupportedType); } public Errors cannotInjectRawTypeLiteral() { return addMessage("Cannot inject a TypeLiteral that has no type parameter"); } public Errors cannotSatisfyCircularDependency(Class<?> expectedType) { return addMessage( "Tried proxying %s to support a circular dependency, but it is not an interface.", expectedType); } public void throwCreationExceptionIfErrorsExist() { if (!hasErrors()) { return; } throw new CreationException(getMessages()); } public void throwConfigurationExceptionIfErrorsExist() { if (!hasErrors()) { return; } throw new ConfigurationException(getMessages()); } public void throwProvisionExceptionIfErrorsExist() { if (!hasErrors()) { return; } throw new ProvisionException(getMessages()); } private Message merge(Message message) { List<Object> sources = new ArrayList<>(); sources.addAll(getSources()); sources.addAll(message.getSources()); return new Message(sources, message.getMessage(), message.getCause()); } public Errors merge(Collection<Message> messages) { for (Message message : messages) { addMessage(merge(message)); } return this; } public Errors merge(Errors moreErrors) { if (moreErrors.root == root || moreErrors.root.errors == null) { return this; } merge(moreErrors.root.errors); return this; } public List<Object> getSources() { List<Object> sources = new ArrayList<>(); for (Errors e = this; e != null; e = e.parent) { if (e.source != SourceProvider.UNKNOWN_SOURCE) { sources.add(0, e.source); } } return sources; } public void throwIfNewErrors(int expectedSize) throws ErrorsException { if (size() == expectedSize) { return; } throw toException(); } public ErrorsException toException() { return new ErrorsException(this); } public boolean hasErrors() { return root.errors != null; } public Errors addMessage(String messageFormat, Object... arguments) { return addMessage(null, messageFormat, arguments); } private Errors addMessage(Throwable cause, String messageFormat, Object... arguments) { String message = format(messageFormat, arguments); addMessage(new Message(getSources(), message, cause)); return this; } public Errors addMessage(Message message) { if (root.errors == null) { root.errors = new ArrayList<>(); } root.errors.add(message); return this; } public static String format(String messageFormat, Object... arguments) { for (int i = 0; i < arguments.length; i++) { arguments[i] = Errors.convert(arguments[i]); } return String.format(Locale.ROOT, messageFormat, arguments); } public List<Message> getMessages() { if (root.errors == null) { return Collections.emptyList(); } List<Message> result = new ArrayList<>(root.errors); CollectionUtil.timSort(result, new Comparator<Message>() { @Override public int compare(Message a, Message b) { return a.getSource().compareTo(b.getSource()); } }); return unmodifiableList(result); } /** * Returns the formatted message for an exception with the specified messages. */ public static String format(String heading, Collection<Message> errorMessages) { try (Formatter fmt = new Formatter(Locale.ROOT)) { fmt.format(heading).format(":%n%n"); int index = 1; boolean displayCauses = getOnlyCause(errorMessages) == null; for (Message errorMessage : errorMessages) { fmt.format("%s) %s%n", index++, errorMessage.getMessage()); List<Object> dependencies = errorMessage.getSources(); for (int i = dependencies.size() - 1; i >= 0; i--) { Object source = dependencies.get(i); formatSource(fmt, source); } Throwable cause = errorMessage.getCause(); if (displayCauses && cause != null) { StringWriter writer = new StringWriter(); cause.printStackTrace(new PrintWriter(writer)); fmt.format("Caused by: %s", writer.getBuffer()); } fmt.format("%n"); } if (errorMessages.size() == 1) { fmt.format("1 error"); } else { fmt.format("%s errors", errorMessages.size()); } return fmt.toString(); } } /** * Returns {@code value} if it is non-null allowed to be null. Otherwise a message is added and * an {@code ErrorsException} is thrown. */ public <T> T checkForNull(T value, Object source, Dependency<?> dependency) throws ErrorsException { if (value != null || dependency.isNullable()) { return value; } int parameterIndex = dependency.getParameterIndex(); String parameterName = (parameterIndex != -1) ? "parameter " + parameterIndex + " of " : ""; addMessage("null returned by binding at %s%n but %s%s is not @Nullable", source, parameterName, dependency.getInjectionPoint().getMember()); throw toException(); } /** * Returns the cause throwable if there is exactly one cause in {@code messages}. If there are * zero or multiple messages with causes, null is returned. */ public static Throwable getOnlyCause(Collection<Message> messages) { Throwable onlyCause = null; for (Message message : messages) { Throwable messageCause = message.getCause(); if (messageCause == null) { continue; } if (onlyCause != null) { return null; } onlyCause = messageCause; } return onlyCause; } public int size() { return root.errors == null ? 0 : root.errors.size(); } private abstract static class Converter<T> { final Class<T> type; Converter(Class<T> type) { this.type = type; } boolean appliesTo(Object o) { return type.isAssignableFrom(o.getClass()); } String convert(Object o) { return toString(type.cast(o)); } abstract String toString(T t); } private static final Collection<Converter<?>> converters = Arrays.asList( new Converter<Class>(Class.class) { @Override public String toString(Class c) { return c.getName(); } }, new Converter<Member>(Member.class) { @Override public String toString(Member member) { return MoreTypes.toString(member); } }, new Converter<Key>(Key.class) { @Override public String toString(Key key) { if (key.getAnnotationType() != null) { return key.getTypeLiteral() + " annotated with " + (key.getAnnotation() != null ? key.getAnnotation() : key.getAnnotationType()); } else { return key.getTypeLiteral().toString(); } } } ); public static Object convert(Object o) { for (Converter<?> converter : converters) { if (converter.appliesTo(o)) { return converter.convert(o); } } return o; } public static void formatSource(Formatter formatter, Object source) { if (source instanceof Dependency) { Dependency<?> dependency = (Dependency<?>) source; InjectionPoint injectionPoint = dependency.getInjectionPoint(); if (injectionPoint != null) { formatInjectionPoint(formatter, dependency, injectionPoint); } else { formatSource(formatter, dependency.getKey()); } } else if (source instanceof InjectionPoint) { formatInjectionPoint(formatter, null, (InjectionPoint) source); } else if (source instanceof Class) { formatter.format(" at %s%n", StackTraceElements.forType((Class<?>) source)); } else if (source instanceof Member) { formatter.format(" at %s%n", StackTraceElements.forMember((Member) source)); } else if (source instanceof TypeLiteral) { formatter.format(" while locating %s%n", source); } else if (source instanceof Key) { Key<?> key = (Key<?>) source; formatter.format(" while locating %s%n", convert(key)); } else { formatter.format(" at %s%n", source); } } public static void formatInjectionPoint(Formatter formatter, Dependency<?> dependency, InjectionPoint injectionPoint) { Member member = injectionPoint.getMember(); Class<? extends Member> memberType = MoreTypes.memberType(member); if (memberType == Field.class) { dependency = injectionPoint.getDependencies().get(0); formatter.format(" while locating %s%n", convert(dependency.getKey())); formatter.format(" for field at %s%n", StackTraceElements.forMember(member)); } else if (dependency != null) { formatter.format(" while locating %s%n", convert(dependency.getKey())); formatter.format(" for parameter %s at %s%n", dependency.getParameterIndex(), StackTraceElements.forMember(member)); } else { formatSource(formatter, injectionPoint.getMember()); } } }