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+/*********************************************************************
+ * Sangria *
+ * Copyright (C) 2014 Tavian Barnes <tavianator@tavianator.com> *
+ * *
+ * This library is free software. It comes without any warranty, to *
+ * the extent permitted by applicable law. You can redistribute it *
+ * and/or modify it under the terms of the Do What The Fuck You Want *
+ * To Public License, Version 2, as published by Sam Hocevar. See *
+ * the COPYING file or http://www.wtfpl.net/ for more details. *
+ *********************************************************************/
+
+package com.tavianator.sangria.contextual;
+
+import com.google.inject.Provider;
+import com.google.inject.spi.InjectionPoint;
+
+/**
+ * Like a {@link Provider}, but with knowledge of the target {@link InjectionPoint}.
+ *
+ * <p>
+ * This interface, along with {@link ContextSensitiveBinder}, is useful for injecting custom logger types, among other
+ * things. However, context-sensitive injections can make maintenance and debugging more difficult.
+ * </p>
+ *
+ * @author Tavian Barnes (tavianator@tavianator.com)
+ * @version 1.0
+ * @since 1.0
+ */
+public interface ContextSensitiveProvider<T> {
+ /**
+ * Provide an instance of {@code T} for the given context.
+ *
+ * @param injectionPoint The {@link InjectionPoint} for this provision.
+ * @return An instance of {@code T}.
+ */
+ T getInContext(InjectionPoint injectionPoint);
+
+ /**
+ * Provide an instance of {@code T} for an unknown context.
+ * <p>
+ * The {@link InjectionPoint} may not be known in all cases, for example if a {@code Provider<T>} is used instead
+ * of
+ * a bare {@code T}. This method will be called in those cases.
+ * </p>
+ * <p>
+ * One reasonable implementation is to return a generically applicable instance, such as an anonymous logger.
+ * Another valid implementation is to throw an unchecked exception; in that case, {@code Provider<T>} injections
+ * will fail.
+ * </p>
+ *
+ * @return An instance of {@code T}
+ * @throws RuntimeException If injection without a context is not supported.
+ */
+ T getInUnknownContext();
+}