home | career | drupal | java | mac | mysql | perl | scala | uml | unix  

Java example source code file (SpiUtils.java)

This example Java source code file (SpiUtils.java) is included in the alvinalexander.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" TM.

Learn more about this Java project at its project page.

Java - Java tags/keywords

binding, bindresult, has_java_optional, indexer, injector, iterable, key, list, mapresult, module, object, optionalbinderbinding, typeliteral, util, visitor

The SpiUtils.java Java example source code

/**
 * Copyright (C) 2010 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.multibindings;

import static com.google.inject.multibindings.MapBinder.entryOfJavaxProviderOf;
import static com.google.inject.multibindings.MapBinder.entryOfProviderOf;
import static com.google.inject.multibindings.MapBinder.mapOf;
import static com.google.inject.multibindings.MapBinder.mapOfCollectionOfJavaxProviderOf;
import static com.google.inject.multibindings.MapBinder.mapOfCollectionOfProviderOf;
import static com.google.inject.multibindings.MapBinder.mapOfJavaxProviderOf;
import static com.google.inject.multibindings.MapBinder.mapOfProviderOf;
import static com.google.inject.multibindings.MapBinder.mapOfSetOfJavaxProviderOf;
import static com.google.inject.multibindings.MapBinder.mapOfSetOfProviderOf;
import static com.google.inject.multibindings.Multibinder.collectionOfJavaxProvidersOf;
import static com.google.inject.multibindings.Multibinder.collectionOfProvidersOf;
import static com.google.inject.multibindings.Multibinder.setOf;
import static com.google.inject.multibindings.OptionalBinder.javaOptionalOfJavaxProvider;
import static com.google.inject.multibindings.OptionalBinder.javaOptionalOfProvider;
import static com.google.inject.multibindings.OptionalBinder.optionalOfJavaxProvider;
import static com.google.inject.multibindings.OptionalBinder.optionalOfProvider;
import static com.google.inject.multibindings.SpiUtils.BindType.INSTANCE;
import static com.google.inject.multibindings.SpiUtils.BindType.LINKED;
import static com.google.inject.multibindings.SpiUtils.BindType.PROVIDER_INSTANCE;
import static com.google.inject.multibindings.SpiUtils.BindType.PROVIDER_KEY;
import static com.google.inject.multibindings.SpiUtils.VisitType.BOTH;
import static com.google.inject.multibindings.SpiUtils.VisitType.INJECTOR;
import static com.google.inject.multibindings.SpiUtils.VisitType.MODULE;
import static junit.framework.Assert.assertEquals;
import static junit.framework.Assert.assertFalse;
import static junit.framework.Assert.assertNotNull;
import static junit.framework.Assert.assertNull;
import static junit.framework.Assert.assertTrue;
import static junit.framework.Assert.fail;

import com.google.common.base.Joiner;
import com.google.common.base.Objects;
import com.google.common.base.Optional;
import com.google.common.collect.ImmutableMap;
import com.google.common.collect.ImmutableSet;
import com.google.common.collect.Lists;
import com.google.common.collect.Maps;
import com.google.common.collect.Multimap;
import com.google.common.collect.MultimapBuilder;
import com.google.common.collect.Sets;
import com.google.inject.Binding;
import com.google.inject.Guice;
import com.google.inject.Injector;
import com.google.inject.Key;
import com.google.inject.Module;
import com.google.inject.Provider;
import com.google.inject.TypeLiteral;
import com.google.inject.multibindings.Indexer.IndexedBinding;
import com.google.inject.multibindings.MapBinder.RealMapBinder.ProviderMapEntry;
import com.google.inject.multibindings.OptionalBinder.Source;
import com.google.inject.spi.DefaultBindingTargetVisitor;
import com.google.inject.spi.Element;
import com.google.inject.spi.Elements;
import com.google.inject.spi.InstanceBinding;
import com.google.inject.spi.LinkedKeyBinding;
import com.google.inject.spi.ProviderInstanceBinding;
import com.google.inject.spi.ProviderKeyBinding;
import com.google.inject.spi.ProviderLookup;

import java.util.HashSet;
import java.util.List;
import java.util.Map;
import java.util.Set;

/**
 * Utilities for testing the Multibinder & MapBinder extension SPI.
 * 
 * @author sameb@google.com (Sam Berlin)
 */
public class SpiUtils {

  private static final boolean HAS_JAVA_OPTIONAL;
  static {
    Class<?> optional = null;
    try {
      optional = Class.forName("java.util.Optional");
    } catch (ClassNotFoundException ignored) {}
    HAS_JAVA_OPTIONAL = optional != null;
  }

  /** The kind of test we should perform.  A live Injector, a raw Elements (Module) test, or both. */
  enum VisitType { INJECTOR, MODULE, BOTH }
  
  /**
   * Asserts that MapBinderBinding visitors for work correctly.
   * 
   * @param <T> The type of the binding
   * @param mapKey The key the map belongs to.
   * @param keyType the TypeLiteral of the key of the map
   * @param valueType the TypeLiteral of the value of the map
   * @param modules The modules that define the mapbindings
   * @param visitType The kind of test we should perform.  A live Injector, a raw Elements (Module) test, or both.
   * @param allowDuplicates If duplicates are allowed.
   * @param expectedMapBindings The number of other mapbinders we expect to see.
   * @param results The kind of bindings contained in the mapbinder.
   */
  static <T> void assertMapVisitor(Key mapKey, TypeLiteral keyType, TypeLiteral valueType,
      Iterable<? extends Module> modules, VisitType visitType, boolean allowDuplicates,
      int expectedMapBindings, MapResult... results) {
    if(visitType == null) {
      fail("must test something");
    }

    if (visitType == BOTH || visitType == INJECTOR) {
      mapInjectorTest(mapKey, keyType, valueType, modules, allowDuplicates, expectedMapBindings,
          results);
    }

    if (visitType == BOTH || visitType == MODULE) {
      mapModuleTest(mapKey, keyType, valueType, modules, allowDuplicates, expectedMapBindings,
          results);
    }
  }
  
  @SuppressWarnings("unchecked")
  private static <T> void mapInjectorTest(Key mapKey, TypeLiteral keyType,
      TypeLiteral<?> valueType, Iterable modules, boolean allowDuplicates,
      int expectedMapBindings, MapResult... results) {
    Injector injector = Guice.createInjector(modules);
    Visitor<T> visitor = new Visitor();
    Binding<T> mapBinding = injector.getBinding(mapKey);
    MapBinderBinding<T> mapbinder = (MapBinderBinding)mapBinding.acceptTargetVisitor(visitor);
    assertNotNull(mapbinder);
    assertEquals(keyType, mapbinder.getKeyTypeLiteral());
    assertEquals(valueType, mapbinder.getValueTypeLiteral());
    assertEquals(allowDuplicates, mapbinder.permitsDuplicates());
    List<Map.Entry> entries = Lists.newArrayList(mapbinder.getEntries());
    List<MapResult> mapResults = Lists.newArrayList(results);
    assertEquals("wrong entries, expected: " + mapResults + ", but was: " + entries,
        mapResults.size(), entries.size());

    for(MapResult result : mapResults) {
      Map.Entry<?, Binding found = null;
      for(Map.Entry<?, Binding entry : entries) {
        Object key = entry.getKey();
        Binding<?> value = entry.getValue();
        if(key.equals(result.k) && matches(value, result.v)) {
          found = entry;
          break;
        }
      }
      if(found == null) {
        fail("Could not find entry: " + result + " in remaining entries: " + entries);
      } else {
        assertTrue("mapBinder doesn't contain: " + found.getValue(), 
            mapbinder.containsElement(found.getValue()));
        entries.remove(found);
      }
    }
    
    if(!entries.isEmpty()) {
      fail("Found all entries of: " + mapResults + ", but more were left over: " + entries);
    }
    
    Key<?> mapOfJavaxProvider = mapKey.ofType(mapOfJavaxProviderOf(keyType, valueType));
    Key<?> mapOfProvider = mapKey.ofType(mapOfProviderOf(keyType, valueType));
    Key<?> mapOfSetOfProvider = mapKey.ofType(mapOfSetOfProviderOf(keyType, valueType));
    Key<?> mapOfSetOfJavaxProvider = mapKey.ofType(mapOfSetOfJavaxProviderOf(keyType, valueType));
    Key<?> mapOfCollectionOfProvider = mapKey.ofType(mapOfCollectionOfProviderOf(keyType, valueType));
    Key<?> mapOfCollectionOfJavaxProvider = mapKey.ofType(mapOfCollectionOfJavaxProviderOf(keyType, valueType));
    Key<?> mapOfSet = mapKey.ofType(mapOf(keyType, setOf(valueType)));
    Key<?> setOfEntry = mapKey.ofType(setOf(entryOfProviderOf(keyType, valueType)));
    Key<?> setOfJavaxEntry = mapKey.ofType(setOf(entryOfJavaxProviderOf(keyType, valueType)));
    Key<?> collectionOfProvidersOfEntryOfProvider =
        mapKey.ofType(collectionOfProvidersOf(entryOfProviderOf(keyType, valueType)));
    Key<?> collectionOfJavaxProvidersOfEntryOfProvider =
        mapKey.ofType(collectionOfJavaxProvidersOf(entryOfProviderOf(keyType, valueType)));
    boolean entrySetMatch = false;
    boolean javaxEntrySetMatch = false;
    boolean mapJavaxProviderMatch = false;
    boolean mapProviderMatch = false;
    boolean mapSetMatch = false; 
    boolean mapSetProviderMatch = false;
    boolean mapSetJavaxProviderMatch = false;
    boolean mapCollectionProviderMatch = false;
    boolean mapCollectionJavaxProviderMatch = false;
    boolean collectionOfProvidersOfEntryOfProviderMatch = false;
    boolean collectionOfJavaxProvidersOfEntryOfProviderMatch = false;
    List<Object> otherMapBindings = Lists.newArrayList();
    List<Binding> otherMatches = Lists.newArrayList();
    Multimap<Object, IndexedBinding> indexedEntries =
        MultimapBuilder.hashKeys().hashSetValues().build();
    Indexer indexer = new Indexer(injector);
    int duplicates = 0;
    for(Binding b : injector.getAllBindings().values()) {
      boolean contains = mapbinder.containsElement(b);      
      Object visited = b.acceptTargetVisitor(visitor);
      if(visited instanceof MapBinderBinding) {
        if(visited.equals(mapbinder)) {
          assertTrue(contains);
        } else {
          otherMapBindings.add(visited);
        }
      } else if(b.getKey().equals(mapOfProvider)) {
        assertTrue(contains);
        mapProviderMatch = true;
      } else if (b.getKey().equals(mapOfJavaxProvider)) {
        assertTrue(contains);
        mapJavaxProviderMatch = true;
      } else if(b.getKey().equals(mapOfSet)) {
        assertTrue(contains);
        mapSetMatch = true;
      } else if(b.getKey().equals(mapOfSetOfProvider)) {
        assertTrue(contains);
        mapSetProviderMatch = true;
      } else if(b.getKey().equals(mapOfSetOfJavaxProvider)) {
        assertTrue(contains);
        mapSetJavaxProviderMatch = true;
      } else if(b.getKey().equals(mapOfCollectionOfProvider)) {
        assertTrue(contains);
        mapCollectionProviderMatch = true;
      } else if(b.getKey().equals(mapOfCollectionOfJavaxProvider)) {
        assertTrue(contains);
        mapCollectionJavaxProviderMatch = true;
      } else if(b.getKey().equals(setOfEntry)) {
        assertTrue(contains);
        entrySetMatch = true;
        // Validate that this binding is also a MultibinderBinding.
        assertTrue(b.acceptTargetVisitor(visitor) instanceof MultibinderBinding);
      } else if(b.getKey().equals(setOfJavaxEntry)) {
        assertTrue(contains);
        javaxEntrySetMatch = true;
      } else if(b.getKey().equals(collectionOfProvidersOfEntryOfProvider)) {
        assertTrue(contains);
        collectionOfProvidersOfEntryOfProviderMatch = true;
      } else if(b.getKey().equals(collectionOfJavaxProvidersOfEntryOfProvider)) {
        assertTrue(contains);
        collectionOfJavaxProvidersOfEntryOfProviderMatch = true;
      } else if (contains) {
        if (b instanceof ProviderInstanceBinding) {
          ProviderInstanceBinding<?> pib = (ProviderInstanceBinding)b;
          if (pib.getUserSuppliedProvider() instanceof ProviderMapEntry) {
            // weird casting required to workaround compilation issues with jdk6
            ProviderMapEntry<?, ?> pme =
                (ProviderMapEntry<?, ?>) (Provider) pib.getUserSuppliedProvider();
            Binding<?> valueBinding = injector.getBinding(pme.getValueKey());
            if (indexer.isIndexable(valueBinding)
                && !indexedEntries.put(pme.getKey(), valueBinding.acceptTargetVisitor(indexer))) {
              duplicates++;
            }
          }
        }
        otherMatches.add(b);
      }
    }
    
    int sizeOfOther = otherMatches.size();
    if(allowDuplicates) {
      sizeOfOther--; // account for 1 duplicate binding
    }
    // Multiply by two because each has a value and Map.Entry.
    int expectedSize = 2 * (mapResults.size() + duplicates);
    assertEquals("Incorrect other matches:\n\t" + Joiner.on("\n\t").join(otherMatches), 
        expectedSize, sizeOfOther);
    assertTrue(entrySetMatch);
    assertTrue(javaxEntrySetMatch);
    assertTrue(mapProviderMatch);
    assertTrue(mapJavaxProviderMatch);
    assertTrue(collectionOfProvidersOfEntryOfProviderMatch);
    assertTrue(collectionOfJavaxProvidersOfEntryOfProviderMatch);
    assertEquals(allowDuplicates, mapSetMatch);
    assertEquals(allowDuplicates, mapSetProviderMatch);
    assertEquals(allowDuplicates, mapSetJavaxProviderMatch);
    assertEquals(allowDuplicates, mapCollectionJavaxProviderMatch);
    assertEquals(allowDuplicates, mapCollectionProviderMatch);
    assertEquals("other MapBindings found: " + otherMapBindings, expectedMapBindings,
        otherMapBindings.size());
  }
  
  @SuppressWarnings("unchecked")
  private static <T> void mapModuleTest(Key mapKey, TypeLiteral keyType,
      TypeLiteral<?> valueType, Iterable modules, boolean allowDuplicates,
      int expectedMapBindings, MapResult... results) {
    Set<Element> elements = ImmutableSet.copyOf(Elements.getElements(modules));
    Visitor<T> visitor = new Visitor();
    MapBinderBinding<T> mapbinder = null;
    Map<Key> keyMap = Maps.newHashMap();
    for(Element element : elements) {
      if(element instanceof Binding) {
        Binding<?> binding = (Binding)element;
        keyMap.put(binding.getKey(), binding);
        if (binding.getKey().equals(mapKey)) {
          mapbinder = (MapBinderBinding<T>)((Binding)binding).acceptTargetVisitor(visitor);
        }
      }
    }
    assertNotNull(mapbinder);
    
    assertEquals(keyType, mapbinder.getKeyTypeLiteral());
    assertEquals(valueType, mapbinder.getValueTypeLiteral());
    List<MapResult> mapResults = Lists.newArrayList(results);
    
    Key<?> mapOfProvider = mapKey.ofType(mapOfProviderOf(keyType, valueType));
    Key<?> mapOfJavaxProvider = mapKey.ofType(mapOfJavaxProviderOf(keyType, valueType));
    Key<?> mapOfSetOfProvider = mapKey.ofType(mapOfSetOfProviderOf(keyType, valueType));
    Key<?> mapOfSetOfJavaxProvider = mapKey.ofType(mapOfSetOfJavaxProviderOf(keyType, valueType));
    Key<?> mapOfCollectionOfProvider = mapKey.ofType(mapOfCollectionOfProviderOf(keyType, valueType));
    Key<?> mapOfCollectionOfJavaxProvider = mapKey.ofType(mapOfCollectionOfJavaxProviderOf(keyType, valueType));
    Key<?> mapOfSet = mapKey.ofType(mapOf(keyType, setOf(valueType)));
    Key<?> setOfEntry = mapKey.ofType(setOf(entryOfProviderOf(keyType, valueType)));
    Key<?> setOfJavaxEntry = mapKey.ofType(setOf(entryOfJavaxProviderOf(keyType, valueType)));
    Key<?> collectionOfProvidersOfEntryOfProvider =
        mapKey.ofType(collectionOfProvidersOf(entryOfProviderOf(keyType, valueType)));
    Key<?> collectionOfJavaxProvidersOfEntryOfProvider =
        mapKey.ofType(collectionOfJavaxProvidersOf(entryOfProviderOf(keyType, valueType)));
    boolean entrySetMatch = false;
    boolean entrySetJavaxMatch = false;
    boolean mapProviderMatch = false;
    boolean mapJavaxProviderMatch = false;
    boolean mapSetMatch = false;
    boolean mapSetProviderMatch = false;
    boolean mapSetJavaxProviderMatch = false;
    boolean mapCollectionProviderMatch = false;
    boolean mapCollectionJavaxProviderMatch = false;
    boolean collectionOfProvidersOfEntryOfProviderMatch = false;
    boolean collectionOfJavaxProvidersOfEntryOfProviderMatch = false;
    List<Object> otherMapBindings = Lists.newArrayList();
    List<Element> otherMatches = Lists.newArrayList();
    List<Element> otherElements = Lists.newArrayList();
    Indexer indexer = new Indexer(null);
    Multimap<Object, IndexedBinding> indexedEntries =
        MultimapBuilder.hashKeys().hashSetValues().build();
    int duplicates = 0;
    for(Element element : elements) {
      boolean contains = mapbinder.containsElement(element);
      if(!contains) {
        otherElements.add(element);
      }
      boolean matched = false;
      Key key = null;
      Binding b = null;
      if(element instanceof Binding) {
        b = (Binding)element;
        if (b instanceof ProviderInstanceBinding) {
          ProviderInstanceBinding<?> pb = (ProviderInstanceBinding) b;
          if (pb.getUserSuppliedProvider() instanceof ProviderMapEntry) {
            // weird casting required to workaround jdk6 compilation problems
            ProviderMapEntry<?, ?> pme =
                (ProviderMapEntry<?, ?>) (Provider) pb.getUserSuppliedProvider();
            Binding<?> valueBinding = keyMap.get(pme.getValueKey());
            if (indexer.isIndexable(valueBinding)
                && !indexedEntries.put(pme.getKey(), valueBinding.acceptTargetVisitor(indexer))) {
              duplicates++;
            }
          }
        }

        key = b.getKey();
        Object visited = b.acceptTargetVisitor(visitor);
        if(visited instanceof MapBinderBinding) {
          matched = true;
          if(visited.equals(mapbinder)) {
            assertTrue(contains);
          } else {
            otherMapBindings.add(visited);
          }
        }
      } else if(element instanceof ProviderLookup) {
        key = ((ProviderLookup)element).getKey();
      }
      
      if(!matched && key != null) {
        if(key.equals(mapOfProvider)) {
          matched = true;
          assertTrue(contains);
          mapProviderMatch = true;
        } else if(key.equals(mapOfJavaxProvider)) {
          matched = true;
          assertTrue(contains);
          mapJavaxProviderMatch = true;
        } else if(key.equals(mapOfSet)) {
          matched = true;
          assertTrue(contains);
          mapSetMatch = true;
        } else if(key.equals(mapOfSetOfProvider)) {
          matched = true;
          assertTrue(contains);
          mapSetProviderMatch = true;
        } else if(key.equals(mapOfSetOfJavaxProvider)) {
          matched = true;
          assertTrue(contains);
          mapSetJavaxProviderMatch = true;
        } else if(key.equals(mapOfCollectionOfProvider)) {
          matched = true;
          assertTrue(contains);
          mapCollectionProviderMatch = true;
        } else if(key.equals(mapOfCollectionOfJavaxProvider)) {
          matched = true;
          assertTrue(contains);
          mapCollectionJavaxProviderMatch = true;
        } else if(key.equals(setOfEntry)) {
          matched = true;
          assertTrue(contains);
          entrySetMatch = true;
          // Validate that this binding is also a MultibinderBinding.
          if(b != null) {
            assertTrue(b.acceptTargetVisitor(visitor) instanceof MultibinderBinding);
          }
        } else if(key.equals(setOfJavaxEntry)) {
          matched = true;
          assertTrue(contains);
          entrySetJavaxMatch = true;
        } else if(key.equals(collectionOfProvidersOfEntryOfProvider)) {
          matched = true;
          assertTrue(contains);
          collectionOfProvidersOfEntryOfProviderMatch = true;
        } else if(key.equals(collectionOfJavaxProvidersOfEntryOfProvider)) {
          matched = true;
          assertTrue(contains);
          collectionOfJavaxProvidersOfEntryOfProviderMatch = true;
        }
      }
      
      if (!matched && contains) {
        otherMatches.add(element);
      }
    }
    
    int otherMatchesSize = otherMatches.size();
    if (allowDuplicates) {
      otherMatchesSize--; // allow for 1 duplicate binding
    }
    // Multiply by 3 because each has a value, ProviderLookup, and Map.Entry
    int expectedSize = (mapResults.size() + duplicates) * 3;
    assertEquals("incorrect number of contains, leftover matches:\n" + Joiner.on("\n\t").join(otherMatches),
        expectedSize, otherMatchesSize);

    assertTrue(entrySetMatch);
    assertTrue(entrySetJavaxMatch);
    assertTrue(mapProviderMatch);
    assertTrue(mapJavaxProviderMatch);
    assertTrue(collectionOfProvidersOfEntryOfProviderMatch);
    assertTrue(collectionOfJavaxProvidersOfEntryOfProviderMatch);
    assertEquals(allowDuplicates, mapSetMatch);
    assertEquals(allowDuplicates, mapSetProviderMatch);
    assertEquals(allowDuplicates, mapSetJavaxProviderMatch);
    assertEquals(allowDuplicates, mapCollectionProviderMatch);
    assertEquals(allowDuplicates, mapCollectionJavaxProviderMatch);
    assertEquals("other MapBindings found: " + otherMapBindings, expectedMapBindings,
        otherMapBindings.size());
    
     // Validate that we can construct an injector out of the remaining bindings.
    Guice.createInjector(Elements.getModule(otherElements));
  }
  
  /**
   * Asserts that MultibinderBinding visitors work correctly.
   * 
   * @param <T> The type of the binding
   * @param setKey The key the set belongs to.
   * @param elementType the TypeLiteral of the element
   * @param modules The modules that define the multibindings
   * @param visitType The kind of test we should perform.  A live Injector, a raw Elements (Module) test, or both.
   * @param allowDuplicates If duplicates are allowed.
   * @param expectedMultibindings The number of other multibinders we expect to see.
   * @param results The kind of bindings contained in the multibinder.
   */
  static <T> void assertSetVisitor(Key> setKey, TypeLiteral elementType,
      Iterable<? extends Module> modules, VisitType visitType, boolean allowDuplicates,
      int expectedMultibindings, BindResult... results) {
    if(visitType == null) {
      fail("must test something");
    }
    
    if(visitType == BOTH || visitType == INJECTOR) {
      setInjectorTest(setKey, elementType, modules, allowDuplicates,
          expectedMultibindings, results);
    }
    
    if(visitType == BOTH || visitType == MODULE) {
      setModuleTest(setKey, elementType, modules, allowDuplicates,
          expectedMultibindings, results);
    }
  }
  
  @SuppressWarnings("unchecked")
  private static <T> void setInjectorTest(Key> setKey, TypeLiteral elementType,
      Iterable<? extends Module> modules, boolean allowDuplicates, int otherMultibindings,
      BindResult... results) {
    Key<?> collectionOfProvidersKey = setKey.ofType(collectionOfProvidersOf(elementType));
    Key<?> collectionOfJavaxProvidersKey =
        setKey.ofType(collectionOfJavaxProvidersOf(elementType));
    Injector injector = Guice.createInjector(modules);
    Visitor<Set visitor = new Visitor>();
    Binding<Set binding = injector.getBinding(setKey);
    MultibinderBinding<Set multibinder =
        (MultibinderBinding<Set)binding.acceptTargetVisitor(visitor);
    assertNotNull(multibinder);
    assertEquals(elementType, multibinder.getElementTypeLiteral());
    assertEquals(allowDuplicates, multibinder.permitsDuplicates());
    List<Binding elements = Lists.newArrayList(multibinder.getElements());
    List<BindResult> bindResults = Lists.newArrayList(results);
    assertEquals("wrong bind elements, expected: " + bindResults
        + ", but was: " + multibinder.getElements(),
        bindResults.size(), elements.size());

    for(BindResult result : bindResults) {
      Binding found = null;
      for(Binding item : elements) {
        if (matches(item, result)) {
          found = item;
          break;
        }
      }
      if(found == null) {
        fail("Could not find element: " + result + " in remaining elements: " + elements);
      } else {
        elements.remove(found);
      }
    }
    
    if(!elements.isEmpty()) {
      fail("Found all elements of: " + bindResults + ", but more were left over: " + elements);
    }

    Set<Binding> setOfElements = new HashSet(multibinder.getElements()); 
    Set<IndexedBinding> setOfIndexed = Sets.newHashSet();
    Indexer indexer = new Indexer(injector);
    for (Binding<?> oneBinding : setOfElements) {
      setOfIndexed.add(oneBinding.acceptTargetVisitor(indexer));
    }

    List<Object> otherMultibinders = Lists.newArrayList();
    List<Binding> otherContains = Lists.newArrayList();
    boolean collectionOfProvidersMatch = false;
    boolean collectionOfJavaxProvidersMatch = false;
    for(Binding b : injector.getAllBindings().values()) {
      boolean contains = multibinder.containsElement(b);
      Key key = b.getKey();
      Object visited = b.acceptTargetVisitor(visitor);
      if(visited != null) {
        if(visited.equals(multibinder)) {
          assertTrue(contains);
        } else {
          otherMultibinders.add(visited);
        }
      } else if(setOfElements.contains(b)) {
        assertTrue(contains);
      } else if (key.equals(collectionOfProvidersKey)) {
        assertTrue(contains);
        collectionOfProvidersMatch = true;
      } else if (key.equals(collectionOfJavaxProvidersKey)) {
        assertTrue(contains);
        collectionOfJavaxProvidersMatch = true;
      } else if (contains) {
        if (!indexer.isIndexable(b) || !setOfIndexed.contains(b.acceptTargetVisitor(indexer))) {
          otherContains.add(b);
        }
      }
    }

    assertTrue(collectionOfProvidersMatch);
    assertTrue(collectionOfJavaxProvidersMatch);

    if(allowDuplicates) {
      assertEquals("contained more than it should: " + otherContains, 1, otherContains.size());
    } else {
      assertTrue("contained more than it should: " + otherContains, otherContains.isEmpty());
    }
    assertEquals("other multibindings found: " + otherMultibinders, otherMultibindings,
        otherMultibinders.size());
    
  }
  
  @SuppressWarnings("unchecked")
  private static <T> void setModuleTest(Key> setKey, TypeLiteral elementType,
      Iterable<? extends Module> modules, boolean allowDuplicates, int otherMultibindings,
      BindResult... results) {
    Key<?> collectionOfProvidersKey = setKey.ofType(collectionOfProvidersOf(elementType));
    Key<?> collectionOfJavaxProvidersKey =
        setKey.ofType(collectionOfJavaxProvidersOf(elementType));
    List<BindResult> bindResults = Lists.newArrayList(results);
    List<Element> elements = Elements.getElements(modules);
    Visitor<T> visitor = new Visitor();
    MultibinderBinding<Set multibinder = null;
    for(Element element : elements) {
      if(element instanceof Binding && ((Binding)element).getKey().equals(setKey)) {
        multibinder = (MultibinderBinding<Set)((Binding)element).acceptTargetVisitor(visitor);
        break;
      }
    }
    assertNotNull(multibinder);

    assertEquals(elementType, multibinder.getElementTypeLiteral());
    List<Object> otherMultibinders = Lists.newArrayList();
    Set<Element> otherContains = new HashSet();
    List<Element> otherElements = Lists.newArrayList();
    int duplicates = 0;
    Set<IndexedBinding> setOfIndexed = Sets.newHashSet();
    Indexer indexer = new Indexer(null);
    boolean collectionOfProvidersMatch = false;
    boolean collectionOfJavaxProvidersMatch = false;
    for(Element element : elements) {
      boolean contains = multibinder.containsElement(element);
      if(!contains) {
        otherElements.add(element);
      }
      boolean matched = false;
      Key key = null;
      if(element instanceof Binding) {
        Binding binding = (Binding)element;
        if (indexer.isIndexable(binding)
            && !setOfIndexed.add((IndexedBinding) binding.acceptTargetVisitor(indexer))) {
          duplicates++;
        }
        key = binding.getKey();
        Object visited = binding.acceptTargetVisitor(visitor);
        if(visited != null) {
          matched = true;
          if(visited.equals(multibinder)) {
            assertTrue(contains);
          } else {
            otherMultibinders.add(visited);
          }
        }
      }

      if (collectionOfProvidersKey.equals(key)) {
        assertTrue(contains);
        assertFalse(matched);
        collectionOfProvidersMatch = true;
      } else if (collectionOfJavaxProvidersKey.equals(key)) {
          assertTrue(contains);
          assertFalse(matched);
          collectionOfJavaxProvidersMatch = true;
      } else if (!matched && contains) {
        otherContains.add(element);
      }
    }

    if(allowDuplicates) {
      assertEquals("wrong contained elements: " + otherContains,
          bindResults.size() + 1 + duplicates, otherContains.size());
    } else {
      assertEquals("wrong contained elements: " + otherContains,
          bindResults.size() + duplicates, otherContains.size());
    }

    assertEquals("other multibindings found: " + otherMultibinders, otherMultibindings,
        otherMultibinders.size());
    assertTrue(collectionOfProvidersMatch);
    assertTrue(collectionOfJavaxProvidersMatch);

    // Validate that we can construct an injector out of the remaining bindings.
    Guice.createInjector(Elements.getModule(otherElements));
  }

  /**
   * Asserts that OptionalBinderBinding visitors for work correctly.
   *
   * @param <T> The type of the binding
   * @param keyType The key OptionalBinder is binding
   * @param modules The modules that define the bindings
   * @param visitType The kind of test we should perform. A live Injector, a raw Elements (Module)
   *        test, or both.
   * @param expectedOtherOptionalBindings the # of other optional bindings we expect to see.
   * @param expectedDefault the expected default binding, or null if none
   * @param expectedActual the expected actual binding, or null if none
   * @param expectedUserLinkedActual the user binding that is the actual binding, used if
   *        neither the default nor actual are set and a user binding existed for the type.
   */
  static <T> void assertOptionalVisitor(Key keyType,
      Iterable<? extends Module> modules,
      VisitType visitType,
      int expectedOtherOptionalBindings,
      BindResult<?> expectedDefault,
      BindResult<?> expectedActual,
      BindResult<?> expectedUserLinkedActual) {
    if (visitType == null) {
      fail("must test something");
    }

    // if java.util.Optional is bound, there'll be twice as many as we expect.
    if (HAS_JAVA_OPTIONAL) {
      expectedOtherOptionalBindings *= 2;
    }

    if (visitType == BOTH || visitType == INJECTOR) {
      optionalInjectorTest(keyType, modules, expectedOtherOptionalBindings, expectedDefault,
          expectedActual, expectedUserLinkedActual);
    }

    if (visitType == BOTH || visitType == MODULE) {
      optionalModuleTest(keyType, modules, expectedOtherOptionalBindings, expectedDefault,
          expectedActual, expectedUserLinkedActual);
    }
  }

  @SuppressWarnings({ "unchecked", "rawtypes" })
  private static <T> void optionalInjectorTest(Key keyType,
      Iterable<? extends Module> modules,
      int expectedOtherOptionalBindings,
      BindResult<?> expectedDefault,
      BindResult<?> expectedActual,
      BindResult<?> expectedUserLinkedActual) {
    if (expectedUserLinkedActual != null) {
      assertNull("cannot have actual if expecting user binding", expectedActual);
      assertNull("cannot have default if expecting user binding", expectedDefault);
    }

    Key<Optional optionalKey =
        keyType.ofType(OptionalBinder.optionalOf(keyType.getTypeLiteral()));
    Key<?> javaOptionalKey = HAS_JAVA_OPTIONAL ?
        keyType.ofType(OptionalBinder.javaOptionalOf(keyType.getTypeLiteral())) : null;
    Injector injector = Guice.createInjector(modules);
    Binding<Optional optionalBinding = injector.getBinding(optionalKey);
    Visitor visitor = new Visitor();
    OptionalBinderBinding<Optional optionalBinder =
        (OptionalBinderBinding<Optional) optionalBinding.acceptTargetVisitor(visitor);
    assertNotNull(optionalBinder);
    assertEquals(optionalKey, optionalBinder.getKey());

    Binding<?> javaOptionalBinding = null;
    OptionalBinderBinding<?> javaOptionalBinder = null;
    if (HAS_JAVA_OPTIONAL) {
      javaOptionalBinding = injector.getBinding(javaOptionalKey);
      javaOptionalBinder = (OptionalBinderBinding<?>) javaOptionalBinding.acceptTargetVisitor(visitor);
      assertNotNull(javaOptionalBinder);
      assertEquals(javaOptionalKey, javaOptionalBinder.getKey());
    }

    if (expectedDefault == null) {
      assertNull("did not expect a default binding", optionalBinder.getDefaultBinding());
      if (HAS_JAVA_OPTIONAL) {
        assertNull("did not expect a default binding", javaOptionalBinder.getDefaultBinding());  
      }
    } else {
      assertTrue("expectedDefault: " + expectedDefault + ", actualDefault: "
              + optionalBinder.getDefaultBinding(),
          matches(optionalBinder.getDefaultBinding(), expectedDefault));
      if (HAS_JAVA_OPTIONAL) {
        assertTrue("expectedDefault: " + expectedDefault + ", actualDefault: "
                + javaOptionalBinder.getDefaultBinding(),
            matches(javaOptionalBinder.getDefaultBinding(), expectedDefault));
      }
    }

    if (expectedActual == null && expectedUserLinkedActual == null) {
      assertNull(optionalBinder.getActualBinding());
      if (HAS_JAVA_OPTIONAL) {
        assertNull(javaOptionalBinder.getActualBinding());  
      }
    } else if (expectedActual != null) {
      assertTrue("expectedActual: " + expectedActual + ", actualActual: "
              + optionalBinder.getActualBinding(),
          matches(optionalBinder.getActualBinding(), expectedActual));
      if (HAS_JAVA_OPTIONAL) {
        assertTrue("expectedActual: " + expectedActual + ", actualActual: "
                + javaOptionalBinder.getActualBinding(),
            matches(javaOptionalBinder.getActualBinding(), expectedActual));
      }
    } else if (expectedUserLinkedActual != null) {
      assertTrue("expectedUserLinkedActual: " + expectedUserLinkedActual + ", actualActual: "
              + optionalBinder.getActualBinding(),
          matches(optionalBinder.getActualBinding(), expectedUserLinkedActual));
      if (HAS_JAVA_OPTIONAL) {
        assertTrue("expectedUserLinkedActual: " + expectedUserLinkedActual + ", actualActual: "
                + javaOptionalBinder.getActualBinding(),
            matches(javaOptionalBinder.getActualBinding(), expectedUserLinkedActual));  
      }
    }


    Key<Optional> optionalJavaxProviderKey =
        keyType.ofType(optionalOfJavaxProvider(keyType.getTypeLiteral()));
    Key<?> javaOptionalJavaxProviderKey = HAS_JAVA_OPTIONAL ?
        keyType.ofType(javaOptionalOfJavaxProvider(keyType.getTypeLiteral())) : null;
    Key<Optional> optionalProviderKey =
        keyType.ofType(optionalOfProvider(keyType.getTypeLiteral()));
    Key<?> javaOptionalProviderKey = HAS_JAVA_OPTIONAL ?
        keyType.ofType(javaOptionalOfProvider(keyType.getTypeLiteral())) : null;

    boolean keyMatch = false;
    boolean optionalKeyMatch = false;
    boolean javaOptionalKeyMatch = false;
    boolean optionalJavaxProviderKeyMatch = false;
    boolean javaOptionalJavaxProviderKeyMatch = false;
    boolean optionalProviderKeyMatch = false;
    boolean javaOptionalProviderKeyMatch = false;
    boolean defaultMatch = false;
    boolean actualMatch = false;
    List<Object> otherOptionalBindings = Lists.newArrayList();
    List<Binding> otherMatches = Lists.newArrayList();
    for (Binding b : injector.getAllBindings().values()) {
      boolean contains = optionalBinder.containsElement(b);
      if (HAS_JAVA_OPTIONAL) {
        assertEquals(contains, javaOptionalBinder.containsElement(b));
      }
      Object visited = b.acceptTargetVisitor(visitor);
      if (visited instanceof OptionalBinderBinding) {
        if (visited.equals(optionalBinder)) {
          assertTrue(contains);
        } else if (HAS_JAVA_OPTIONAL && visited.equals(javaOptionalBinder)) {
          assertTrue(contains);
        } else {
          otherOptionalBindings.add(visited);
        }
      }
      if (b.getKey().equals(keyType)) {
        // keyType might match because a user bound it
        // (which is possible in a purely absent OptionalBinder)
        assertEquals(expectedDefault != null || expectedActual != null, contains);
        if (contains) {
          keyMatch = true;
        }
      } else if (b.getKey().equals(optionalKey)) {
        assertTrue(contains);
        optionalKeyMatch = true;
      } else if (b.getKey().equals(javaOptionalKey)) {
        assertTrue(contains);
        javaOptionalKeyMatch = true;
      } else if (b.getKey().equals(optionalJavaxProviderKey)) {
        assertTrue(contains);
        optionalJavaxProviderKeyMatch = true;
      } else if (b.getKey().equals(javaOptionalJavaxProviderKey)) {
        assertTrue(contains);
        javaOptionalJavaxProviderKeyMatch = true;
      } else if (b.getKey().equals(optionalProviderKey)) {
        assertTrue(contains);
        optionalProviderKeyMatch = true;
      } else if (b.getKey().equals(javaOptionalProviderKey)) {
        assertTrue(contains);
        javaOptionalProviderKeyMatch = true;
      } else if (expectedDefault != null && matches(b, expectedDefault)) {
        assertTrue(contains);
        defaultMatch = true;
      } else if (expectedActual != null && matches(b, expectedActual)) {
        assertTrue(contains);
        actualMatch = true;
      } else if (contains) {
        otherMatches.add(b);
      }
    }

    assertEquals(otherMatches.toString(), 0, otherMatches.size());
    // only expect a keymatch if either default or actual are set
    assertEquals(expectedDefault != null || expectedActual != null, keyMatch);
    assertTrue(optionalKeyMatch);
    assertTrue(optionalJavaxProviderKeyMatch);
    assertTrue(optionalProviderKeyMatch);
    assertEquals(HAS_JAVA_OPTIONAL, javaOptionalKeyMatch);
    assertEquals(HAS_JAVA_OPTIONAL, javaOptionalJavaxProviderKeyMatch);
    assertEquals(HAS_JAVA_OPTIONAL, javaOptionalProviderKeyMatch);
    assertEquals(expectedDefault != null, defaultMatch);
    assertEquals(expectedActual != null, actualMatch);
    assertEquals("other OptionalBindings found: " + otherOptionalBindings,
        expectedOtherOptionalBindings, otherOptionalBindings.size());
  }

  @SuppressWarnings({ "unchecked", "rawtypes" })
  private static <T> void optionalModuleTest(Key keyType,
      Iterable<? extends Module> modules,
      int expectedOtherOptionalBindings,
      BindResult<?> expectedDefault,
      BindResult<?> expectedActual,
      BindResult<?> expectedUserLinkedActual) {
    if (expectedUserLinkedActual != null) {
      assertNull("cannot have actual if expecting user binding", expectedActual);
      assertNull("cannot have default if expecting user binding", expectedDefault);
    }
    Set<Element> elements = ImmutableSet.copyOf(Elements.getElements(modules));
    Map<Key> indexed = index(elements);
    Key<Optional optionalKey =
        keyType.ofType(OptionalBinder.optionalOf(keyType.getTypeLiteral()));
    Key<?> javaOptionalKey = HAS_JAVA_OPTIONAL ?
        keyType.ofType(OptionalBinder.javaOptionalOf(keyType.getTypeLiteral())) : null;
    Visitor visitor = new Visitor();
    OptionalBinderBinding<Optional optionalBinder = null;
    OptionalBinderBinding<?> javaOptionalBinder = null;
    Key<?> defaultKey = null;
    Key<?> actualKey = null;

    Binding optionalBinding = indexed.get(optionalKey);
    optionalBinder =
        (OptionalBinderBinding<Optional) optionalBinding.acceptTargetVisitor(visitor);

    if (HAS_JAVA_OPTIONAL) {
      Binding javaOptionalBinding = indexed.get(javaOptionalKey);
      javaOptionalBinder = (OptionalBinderBinding) javaOptionalBinding.acceptTargetVisitor(visitor);
    }

    // Locate the defaultKey & actualKey
    for (Element element : elements) {
      if (optionalBinder.containsElement(element) && element instanceof Binding) {
        Binding binding = (Binding) element;
        if (isSourceEntry(binding, Source.DEFAULT)) {
          defaultKey = binding.getKey();
        } else if (isSourceEntry(binding, Source.ACTUAL)) {
          actualKey = binding.getKey();
        }
      }
    }
    assertNotNull(optionalBinder);
    if (HAS_JAVA_OPTIONAL) {
      assertNotNull(javaOptionalBinder);
    }
    assertEquals(expectedDefault == null, defaultKey == null);
    assertEquals(expectedActual == null, actualKey == null);

    Key<Optional> optionalJavaxProviderKey =
        keyType.ofType(optionalOfJavaxProvider(keyType.getTypeLiteral()));
    Key<?> javaOptionalJavaxProviderKey = HAS_JAVA_OPTIONAL ?
        keyType.ofType(javaOptionalOfJavaxProvider(keyType.getTypeLiteral())) : null;
    Key<Optional> optionalProviderKey =
        keyType.ofType(optionalOfProvider(keyType.getTypeLiteral()));
    Key<?> javaOptionalProviderKey = HAS_JAVA_OPTIONAL ?
        keyType.ofType(javaOptionalOfProvider(keyType.getTypeLiteral())) : null;
    boolean keyMatch = false;
    boolean optionalKeyMatch = false;
    boolean javaOptionalKeyMatch = false;
    boolean optionalJavaxProviderKeyMatch = false;
    boolean javaOptionalJavaxProviderKeyMatch = false;
    boolean optionalProviderKeyMatch = false;
    boolean javaOptionalProviderKeyMatch = false;
    boolean defaultMatch = false;
    boolean actualMatch = false;
    List<Object> otherOptionalElements = Lists.newArrayList();
    List<Element> otherContains = Lists.newArrayList();
    List<Element> nonContainedElements = Lists.newArrayList();
    for (Element element : elements) {
      boolean contains = optionalBinder.containsElement(element);
      if (HAS_JAVA_OPTIONAL) {
        assertEquals(contains, javaOptionalBinder.containsElement(element));
      }
      if (!contains) {
        nonContainedElements.add(element);
      }
      Key key = null;
      Binding b = null;
      if (element instanceof Binding) {
        b = (Binding) element;
        key = b.getKey();
        Object visited = b.acceptTargetVisitor(visitor);
        if (visited instanceof OptionalBinderBinding) {
          if (visited.equals(optionalBinder)) {
            assertTrue(contains);
          } else if (HAS_JAVA_OPTIONAL && visited.equals(javaOptionalBinder)) {
            assertTrue(contains);
          } else {
            otherOptionalElements.add(visited);
          }
        }
      } else if (element instanceof ProviderLookup) {
        key = ((ProviderLookup) element).getKey();
      }

      if (key != null && key.equals(keyType)) {
        // keyType might match because a user bound it
        // (which is possible in a purely absent OptionalBinder)
        assertEquals(expectedDefault != null || expectedActual != null, contains);
        if (contains) {
          keyMatch = true;
        }
      } else if (key != null && key.equals(optionalKey)) {
        assertTrue(contains);
        optionalKeyMatch = true;
      } else if (key != null && key.equals(javaOptionalKey)) {
        assertTrue(contains);
        javaOptionalKeyMatch = true;
      } else if (key != null && key.equals(optionalJavaxProviderKey)) {
        assertTrue(contains);
        optionalJavaxProviderKeyMatch = true;
      } else if (key != null && key.equals(javaOptionalJavaxProviderKey)) {
        assertTrue(contains);
        javaOptionalJavaxProviderKeyMatch = true;
      } else if (key != null && key.equals(optionalProviderKey)) {
        assertTrue(contains);
        optionalProviderKeyMatch = true;
      } else if (key != null && key.equals(javaOptionalProviderKey)) {
        assertTrue(contains);
        javaOptionalProviderKeyMatch = true;
      } else if (key != null && key.equals(defaultKey)) {
        assertTrue(contains);
        if (b != null) { // otherwise it might just be a ProviderLookup into it
          assertTrue("expected: " + expectedDefault + ", but was: " + b,
              matches(b, expectedDefault));
          defaultMatch = true;
        }
      } else if (key != null && key.equals(actualKey)) {
        assertTrue(contains);
        if (b != null) { // otherwise it might just be a ProviderLookup into it
          assertTrue("expected: " + expectedActual + ", but was: " + b, matches(b, expectedActual));
          actualMatch = true;
        }
      } else if (contains) {
        otherContains.add(element);
      }
    }
    
    // only expect a keymatch if either default or actual are set
    assertEquals(expectedDefault != null || expectedActual != null, keyMatch);
    assertTrue(optionalKeyMatch);
    assertTrue(optionalJavaxProviderKeyMatch);
    assertTrue(optionalProviderKeyMatch);
    assertEquals(HAS_JAVA_OPTIONAL, javaOptionalKeyMatch);
    assertEquals(HAS_JAVA_OPTIONAL, javaOptionalJavaxProviderKeyMatch);
    assertEquals(HAS_JAVA_OPTIONAL, javaOptionalProviderKeyMatch);
    assertEquals(expectedDefault != null, defaultMatch);
    assertEquals(expectedActual != null, actualMatch);
    assertEquals(otherContains.toString(), 0, otherContains.size());
    assertEquals("other OptionalBindings found: " + otherOptionalElements,
        expectedOtherOptionalBindings, otherOptionalElements.size());
    
     // Validate that we can construct an injector out of the remaining bindings.
    Guice.createInjector(Elements.getModule(nonContainedElements));
  }

  private static boolean isSourceEntry(Binding b, Source type) {
    switch(type) {
      case ACTUAL:
        return b.getKey().getAnnotation() instanceof OptionalBinder.Actual;
      case DEFAULT:
        return b.getKey().getAnnotation() instanceof OptionalBinder.Default;
      default:
        throw new IllegalStateException("invalid type: " + type);
    }
  }

  /** Returns the subset of elements that have keys, indexed by them. */
  private static Map<Key> index(Iterable elements) {
    ImmutableMap.Builder<Key> builder = ImmutableMap.builder();
    for (Element element : elements) {
      if (element instanceof Binding) {
        builder.put(((Binding) element).getKey(), (Binding) element);
      }
    }
    return builder.build();
  }
  
  static <K, V> MapResult instance(K k, V v) {
    return new MapResult<K, V>(k, new BindResult(INSTANCE, v, null));
  }

  static <K, V> MapResult linked(K k, Class clazz) {
    return new MapResult<K, V>(k, new BindResult(LINKED, null, Key.get(clazz)));
  }

  static <K, V> MapResult linked(K k, Key key) {
    return new MapResult<K, V>(k, new BindResult(LINKED, null, key));
  }

  static <K, V> MapResult providerInstance(K k, V v) {
    return new MapResult<K, V>(k, new BindResult(PROVIDER_INSTANCE, v, null));
  }

  static class MapResult<K, V> {
    private final K k;
    private final BindResult<V> v;
    
    MapResult(K k, BindResult<V> v) {
      this.k = k;
      this.v = v;
    }
    
    @Override
    public String toString() {
      return "entry[key[" + k + "],value[" + v + "]]";
    }
  }  
  
  private static boolean matches(Binding<?> item, BindResult result) {
    switch (result.type) {
    case INSTANCE:
      if (item instanceof InstanceBinding
          && ((InstanceBinding) item).getInstance().equals(result.instance)) {
        return true;
      }
      break;
    case LINKED:
      if (item instanceof LinkedKeyBinding
          && ((LinkedKeyBinding) item).getLinkedKey().equals(result.key)) {
        return true;
      }
      break;
    case PROVIDER_INSTANCE:
      if (item instanceof ProviderInstanceBinding
          && Objects.equal(((ProviderInstanceBinding) item).getUserSuppliedProvider().get(),
                           result.instance)) {
        return true;
      }
      break;
    case PROVIDER_KEY:
      if (item instanceof ProviderKeyBinding
          && ((ProviderKeyBinding) item).getProviderKey().equals(result.key)) {
        return true;
      }
      break;
    }
    return false;
  }

  static <T> BindResult instance(T t) {
    return new BindResult<T>(INSTANCE, t, null);
  }

  static <T> BindResult linked(Class clazz) {
    return new BindResult<T>(LINKED, null, Key.get(clazz));
  }

  static <T> BindResult linked(Key key) {
    return new BindResult<T>(LINKED, null, key);
  }

  static <T> BindResult providerInstance(T t) {
    return new BindResult<T>(PROVIDER_INSTANCE, t, null);
  }

  static <T> BindResult providerKey(Key key) {
    return new BindResult<T>(PROVIDER_KEY, null, key);
  }
  
  /** The kind of binding. */
  static enum BindType { INSTANCE, LINKED, PROVIDER_INSTANCE, PROVIDER_KEY }
  /** The result of the binding. */
  static class BindResult<T> {
    private final BindType type;
    private final Key<?> key;
    private final T instance;
    
    private BindResult(BindType type, T instance, Key<?> key) {
      this.type = type;
      this.instance = instance;
      this.key = key;
    }
    
    @Override
    public String toString() {
      switch(type) {
      case INSTANCE:
        return "instance[" + instance + "]";
      case LINKED:
        return "linkedKey[" + key + "]";
      case PROVIDER_INSTANCE:
        return "providerInstance[" + instance + "]";
      case PROVIDER_KEY:
        return "providerKey[" + key + "]";
      }
      return null;
    }
  }
  
  private static class Visitor<T> extends
      DefaultBindingTargetVisitor<T, Object> implements MultibindingsTargetVisitor {
  
    public Object visit(MultibinderBinding<? extends T> multibinding) {
      return multibinding;
    }
  
    public Object visit(MapBinderBinding<? extends T> mapbinding) {
      return mapbinding;
    }
    
    public Object visit(OptionalBinderBinding<? extends T> optionalbinding) {
      return optionalbinding;
    }
  }
}

Other Java examples (source code examples)

Here is a short list of links related to this Java SpiUtils.java source code file:



my book on functional programming

 

new blog posts

 

Copyright 1998-2021 Alvin Alexander, alvinalexander.com
All Rights Reserved.

A percentage of advertising revenue from
pages under the /java/jwarehouse URI on this website is
paid back to open source projects.