com.google.common.collect.ImmutableClassToInstanceMap#of ( )源码实例Demo

private FakeSpawnExecutionContext getSpawnContext(Spawn spawn) {
  AbstractSpawnStrategy fakeLocalStrategy = new AbstractSpawnStrategy(execRoot, localRunner) {};
  ClassToInstanceMap<ActionContext> actionContextRegistry =
      ImmutableClassToInstanceMap.of(RemoteLocalFallbackRegistry.class, () -> fakeLocalStrategy);
  return new FakeSpawnExecutionContext(
      spawn, fakeFileCache, execRoot, outErr, actionContextRegistry);
}
 

@Test
public void givenClassToInstanceMap_whenGetCalled_returnUpperBoundElement() {
    ClassToInstanceMap<Action> map = ImmutableClassToInstanceMap.of(Save.class, new Save());
    Action action = map.get(Save.class);
    assertTrue(action instanceof Save);

    // Use getInstance to avoid casting
    Save save = map.getInstance(Save.class);
}
 

PluginRegistry() {
    this(ImmutableClassToInstanceMap.of());
}
 

@Override
public ClassToInstanceMap<NormalizedNodeStreamWriterExtension> getExtensions() {
    return ImmutableClassToInstanceMap.of(StreamWriterMountPointExtension.class, this);
}
 

@Override
public final ClassToInstanceMap<NormalizedNodeStreamWriterExtension> getExtensions() {
    return ImmutableClassToInstanceMap.of(StreamWriterMetadataExtension.class, this);
}
 

@Override
public final ClassToInstanceMap<NormalizedNodeStreamWriterExtension> getExtensions() {
    return ImmutableClassToInstanceMap.of(StreamWriterMountPointExtension.class, this);
}
 

@Override
public final ClassToInstanceMap<NormalizedNodeStreamWriterExtension> getExtensions() {
    return ImmutableClassToInstanceMap.of(StreamWriterMetadataExtension.class, this);
}
 

public FakeSpawnExecutionContext(
    Spawn spawn, MetadataProvider metadataProvider, Path execRoot, FileOutErr outErr) {
  this(spawn, metadataProvider, execRoot, outErr, ImmutableClassToInstanceMap.of());
}
 

@Test
public void whenOfCalled_thenCreateEmptyImmutableMap() {
    ClassToInstanceMap<Action> map = ImmutableClassToInstanceMap.of();
    assertTrue(map.isEmpty());
}
 

@Test
public void whenOfWithParameterCalled_thenCreateSingleEntryMap() {
    ClassToInstanceMap<Action> map = ImmutableClassToInstanceMap.of(Save.class, new Save());
    assertEquals(1, map.size());
}
 

/**
 * Return a map of currently-supported extensions, along with accessor objects which provide access to the specific
 * functionality bound to this object.
 *
 * @return A map of supported functionality.
 */
default @NonNull ClassToInstanceMap<E> getExtensions() {
    return ImmutableClassToInstanceMap.of();
}