All Downloads are FREE. Search and download functionalities are using the official Maven repository.

shaded.com.google.inject.internal.Annotations Maven / Gradle / Ivy

There is a newer version: 4.1.4
Show newest version
/*
 * 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 shaded.shaded.com.google.inject.internal;

import static java.lang.annotation.RetentionPolicy.RUNTIME;

import shaded.shaded.com.google.common.base.Joiner;
import shaded.shaded.com.google.common.base.Joiner.MapJoiner;
import shaded.shaded.com.google.common.base.Preconditions;
import shaded.shaded.com.google.common.cache.CacheBuilder;
import shaded.shaded.com.google.common.cache.CacheLoader;
import shaded.shaded.com.google.common.cache.LoadingCache;
import shaded.shaded.com.google.common.collect.ImmutableMap;
import shaded.shaded.com.google.common.collect.Maps;
import shaded.shaded.com.google.inject.BindingAnnotation;
import shaded.shaded.com.google.inject.Key;
import shaded.shaded.com.google.inject.ScopeAnnotation;
import shaded.shaded.com.google.inject.TypeLiteral;
import shaded.shaded.com.google.inject.internal.util.Classes;
import shaded.shaded.com.google.inject.name.Named;
import shaded.shaded.com.google.inject.name.Names;
import java.lang.annotation.Annotation;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.lang.reflect.InvocationHandler;
import java.lang.reflect.Member;
import java.lang.reflect.Method;
import java.lang.reflect.Proxy;
import java.util.Arrays;
import java.util.Collection;
import java.util.Map;
import javax.inject.Qualifier;

/**
 * Annotation utilities.
 *
 * @author [email protected] (Bob Lee)
 */
public class Annotations {

  /** Returns {@code true} if the given annotation type has no attributes. */
  public static boolean isMarker(Class annotationType) {
    return annotationType.getDeclaredMethods().length == 0;
  }

  public static boolean isAllDefaultMethods(Class annotationType) {
    boolean hasMethods = false;
    for (Method m : annotationType.getDeclaredMethods()) {
      hasMethods = true;
      if (m.getDefaultValue() == null) {
        return false;
      }
    }
    return hasMethods;
  }

  private static final LoadingCache, Annotation> cache =
      CacheBuilder.newBuilder()
          .weakKeys()
          .build(
              new CacheLoader, Annotation>() {
                @Override
                public Annotation load(Class input) {
                  return generateAnnotationImpl(input);
                }
              });

  /**
   * Generates an Annotation for the annotation class. Requires that the annotation is all
   * optionals.
   */
  @SuppressWarnings("unchecked") // Safe because generateAnnotationImpl returns T for Class
  public static  T generateAnnotation(Class annotationType) {
    Preconditions.checkState(
        isAllDefaultMethods(annotationType), "%s is not all default methods", annotationType);
    return (T) cache.getUnchecked(annotationType);
  }

  private static  T generateAnnotationImpl(final Class annotationType) {
    final Map members = resolveMembers(annotationType);
    return annotationType.cast(
        Proxy.newProxyInstance(
            annotationType.getClassLoader(),
            new Class[] {annotationType},
            new InvocationHandler() {
              @Override
              public Object invoke(Object proxy, Method method, Object[] args) throws Exception {
                String name = method.getName();
                if (name.equals("annotationType")) {
                  return annotationType;
                } else if (name.equals("toString")) {
                  return annotationToString(annotationType, members);
                } else if (name.equals("hashCode")) {
                  return annotationHashCode(annotationType, members);
                } else if (name.equals("equals")) {
                  return annotationEquals(annotationType, members, args[0]);
                } else {
                  return members.get(name);
                }
              }
            }));
  }

  private static ImmutableMap resolveMembers(
      Class annotationType) {
    ImmutableMap.Builder result = ImmutableMap.builder();
    for (Method method : annotationType.getDeclaredMethods()) {
      result.put(method.getName(), method.getDefaultValue());
    }
    return result.build();
  }

  /** Implements {@link Annotation#equals}. */
  private static boolean annotationEquals(
      Class type, Map members, Object other)
      throws Exception {
    if (!type.isInstance(other)) {
      return false;
    }
    for (Method method : type.getDeclaredMethods()) {
      String name = method.getName();
      if (!Arrays.deepEquals(
          new Object[] {method.invoke(other)}, new Object[] {members.get(name)})) {
        return false;
      }
    }
    return true;
  }

  /** Implements {@link Annotation#hashCode}. */
  private static int annotationHashCode(
      Class type, Map members) throws Exception {
    int result = 0;
    for (Method method : type.getDeclaredMethods()) {
      String name = method.getName();
      Object value = members.get(name);
      result += (127 * name.hashCode()) ^ (Arrays.deepHashCode(new Object[] {value}) - 31);
    }
    return result;
  }

  private static final MapJoiner JOINER = Joiner.on(", ").withKeyValueSeparator("=");

  /** Implements {@link Annotation#toString}. */
  private static String annotationToString(
      Class type, Map members) throws Exception {
    StringBuilder sb = new StringBuilder().append("@").append(type.getName()).append("(");
    JOINER.appendTo(
        sb,
        Maps.transformValues(
            members,
            arg -> {
              String s = Arrays.deepToString(new Object[] {arg});
              return s.substring(1, s.length() - 1); // cut off brackets
            }));
    return sb.append(")").toString();
  }

  /** Returns true if the given annotation is retained at runtime. */
  public static boolean isRetainedAtRuntime(Class annotationType) {
    Retention retention = annotationType.getAnnotation(Retention.class);
    return retention != null && retention.value() == RetentionPolicy.RUNTIME;
  }

  /** Returns the scope annotation on {@code type}, or null if none is specified. */
  public static Class findScopeAnnotation(
      Errors errors, Class implementation) {
    return findScopeAnnotation(errors, implementation.getAnnotations());
  }

  /** Returns the scoping annotation, or null if there isn't one. */
  public static Class findScopeAnnotation(
      Errors errors, Annotation[] annotations) {
    Class found = null;

    for (Annotation annotation : annotations) {
      Class annotationType = annotation.annotationType();
      if (isScopeAnnotation(annotationType)) {
        if (found != null) {
          errors.duplicateScopeAnnotations(found, annotationType);
        } else {
          found = annotationType;
        }
      }
    }

    return found;
  }

  static boolean containsComponentAnnotation(Annotation[] annotations) {
    for (Annotation annotation : annotations) {
      // TODO(user): Should we scope this down to dagger.Component?
      if (annotation.annotationType().getSimpleName().equals("Component")) {
        return true;
      }
    }

    return false;
  }

  private static class AnnotationToStringConfig {
    final boolean quote;
    final boolean includeMemberName;

    AnnotationToStringConfig(boolean quote, boolean includeMemberName) {
      this.quote = quote;
      this.includeMemberName = includeMemberName;
    }
  }

  private static final AnnotationToStringConfig ANNOTATION_TO_STRING_CONFIG =
      determineAnnotationToStringConfig();

  /**
   * Returns {@code value}, quoted if annotation implementations quote their member values. In Java
   * 9, annotations quote their string members.
   */
  public static String memberValueString(String value) {
    return ANNOTATION_TO_STRING_CONFIG.quote ? "\"" + value + "\"" : value;
  }

  /**
   * Returns string representation of the annotation memeber.
   *
   * 

The value of the member is prefixed with `memberName=` unless the runtime omits the member * name. The value of the member is quoted if annotation implementations quote their member values * and the value type is String. * *

In Java 9, annotations quote their string members and in Java 15, the member name is * omitted. */ public static String memberValueString(String memberName, Object value) { StringBuilder sb = new StringBuilder(); boolean quote = ANNOTATION_TO_STRING_CONFIG.quote; boolean includeMemberName = ANNOTATION_TO_STRING_CONFIG.includeMemberName; if (includeMemberName) { sb.append(memberName).append('='); } if (quote && (value instanceof String)) { sb.append('"').append(value).append('"'); } else { sb.append(value); } return sb.toString(); } @Retention(RUNTIME) private @interface TestAnnotation { String value(); } @TestAnnotation("determineAnnotationToStringConfig") private static AnnotationToStringConfig determineAnnotationToStringConfig() { try { String annotation = Annotations.class .getDeclaredMethod("determineAnnotationToStringConfig") .getAnnotation(TestAnnotation.class) .toString(); boolean quote = annotation.contains("\"determineAnnotationToStringConfig\""); boolean includeMemberName = annotation.contains("value="); return new AnnotationToStringConfig(quote, includeMemberName); } catch (NoSuchMethodException e) { throw new AssertionError(e); } } /** Checks for the presence of annotations. Caches results because Android doesn't. */ static class AnnotationChecker { private final Collection> annotationTypes; /** Returns true if the given class has one of the desired annotations. */ private CacheLoader, Boolean> hasAnnotations = new CacheLoader, Boolean>() { @Override public Boolean load(Class annotationType) { for (Annotation annotation : annotationType.getAnnotations()) { if (annotationTypes.contains(annotation.annotationType())) { return true; } } return false; } }; final LoadingCache, Boolean> cache = CacheBuilder.newBuilder().weakKeys().build(hasAnnotations); /** Constructs a new checker that looks for annotations of the given types. */ AnnotationChecker(Collection> annotationTypes) { this.annotationTypes = annotationTypes; } /** Returns true if the given type has one of the desired annotations. */ boolean hasAnnotations(Class annotated) { return cache.getUnchecked(annotated); } } private static final AnnotationChecker scopeChecker = new AnnotationChecker(Arrays.asList(ScopeAnnotation.class, javax.inject.Scope.class)); public static boolean isScopeAnnotation(Class annotationType) { return scopeChecker.hasAnnotations(annotationType); } /** * Adds an error if there is a misplaced annotations on {@code type}. Scoping annotations are not * allowed on abstract classes or interfaces. */ public static void checkForMisplacedScopeAnnotations( Class type, Object source, Errors errors) { if (Classes.isConcrete(type)) { return; } Class scopeAnnotation = findScopeAnnotation(errors, type); if (scopeAnnotation != null // We let Dagger Components through to aid migrations. && !containsComponentAnnotation(type.getAnnotations())) { errors.withSource(type).scopeAnnotationOnAbstractType(scopeAnnotation, type, source); } } // NOTE: getKey/findBindingAnnotation are used by Gin which is abandoned. So changing this API // will prevent Gin users from upgrading Guice version. /** Gets a key for the given type, member and annotations. */ public static Key getKey( TypeLiteral type, Member member, Annotation[] annotations, Errors errors) throws ErrorsException { int numErrorsBefore = errors.size(); Annotation found = findBindingAnnotation(errors, member, annotations); errors.throwIfNewErrors(numErrorsBefore); return found == null ? Key.get(type) : Key.get(type, found); } /** Returns the binding annotation on {@code member}, or null if there isn't one. */ public static Annotation findBindingAnnotation( Errors errors, Member member, Annotation[] annotations) { Annotation found = null; for (Annotation annotation : annotations) { Class annotationType = annotation.annotationType(); if (isBindingAnnotation(annotationType)) { if (found != null) { errors.duplicateBindingAnnotations(member, found.annotationType(), annotationType); } else { found = annotation; } } } return found; } private static final AnnotationChecker bindingAnnotationChecker = new AnnotationChecker(Arrays.asList(BindingAnnotation.class, Qualifier.class)); /** Returns true if annotations of the specified type are binding annotations. */ public static boolean isBindingAnnotation(Class annotationType) { return bindingAnnotationChecker.hasAnnotations(annotationType); } /** * If the annotation is an instance of {@code javax.inject.Named}, canonicalizes to * shaded.shaded.com.google.guice.name.Named. Returns the given annotation otherwise. */ public static Annotation canonicalizeIfNamed(Annotation annotation) { if (annotation instanceof javax.inject.Named) { return Names.named(((javax.inject.Named) annotation).value()); } else { return annotation; } } /** * If the annotation is the class {@code javax.inject.Named}, canonicalizes to * shaded.shaded.com.google.guice.name.Named. Returns the given annotation class otherwise. */ public static Class canonicalizeIfNamed( Class annotationType) { if (annotationType == javax.inject.Named.class) { return Named.class; } else { return annotationType; } } /** * Returns the name the binding should use. This is based on the annotation. If the annotation has * an instance and is not a marker annotation, we ask the annotation for its toString. If it was a * marker annotation or just an annotation type, we use the annotation's name. Otherwise, the name * is the empty string. */ public static String nameOf(Key key) { Annotation annotation = key.getAnnotation(); Class annotationType = key.getAnnotationType(); if (annotation != null && !isMarker(annotationType)) { return key.getAnnotation().toString(); } else if (key.getAnnotationType() != null) { return "@" + key.getAnnotationType().getName(); } else { return ""; } } }





© 2015 - 2024 Weber Informatics LLC | Privacy Policy