Example usage for com.google.common.base Optional absent

Introduction

In this page you can find the example usage for com.google.common.base Optional absent.

Prototype

public static <T> Optional<T> absent()

Source Link

Document

Returns an Optional instance with no contained reference.

Usage

From source file:com.rentmycourt.api.core.helpers.SimpleAuthenticator.java

/**
 *
 * @param credentials/*from w  w w  .j a va  2 s. c o m*/
 * @return
 * @throws io.dropwizard.auth.AuthenticationException.<error>
 */
@Override
public Optional<User> authenticate(BasicCredentials credentials) throws AuthenticationException {
    if ("secret".equals(credentials.getPassword())) {
        return Optional.of(new User(credentials.getUsername()));
    }
    return Optional.absent();
}

From source file:org.opendaylight.groupbasedpolicy.util.DataStoreHelper.java

/**
 * Reads data from datastore as synchrone call.
 * @return {@link Optional#isPresent()} is {@code true} if reading was successful and data exists in datastore; {@link Optional#isPresent()} is {@code false} otherwise
 *//*from   w w  w .  ja v a 2  s  . c om*/
public static <T extends DataObject> Optional<T> readFromDs(LogicalDatastoreType store,
        InstanceIdentifier<T> path, ReadTransaction rTx) {
    CheckedFuture<Optional<T>, ReadFailedException> resultFuture = rTx.read(store, path);
    try {
        return resultFuture.checkedGet();
    } catch (ReadFailedException e) {
        LOG.warn("Read failed from DS.", e);
        return Optional.absent();
    }
}

From source file:cc.ilo.cc.ilo.pipeline.pipes.AbstractFilterPipe.java

@Override
public Optional<T> process(T input) throws Exception {
    if (accept(input)) {
        return Optional.of(input);
    } else {//from ww w  .  j av  a  2 s. c  o  m
        return Optional.absent();
    }

}

From source file:dagger2.internal.codegen.InjectionAnnotations.java

static Optional<AnnotationMirror> getQualifier(Element e) {
    checkNotNull(e);/*from   www  .j  ava  2  s. c  o m*/
    ImmutableSet<? extends AnnotationMirror> qualifierAnnotations = getQualifiers(e);
    switch (qualifierAnnotations.size()) {
    case 0:
        return Optional.absent();
    case 1:
        return Optional.<AnnotationMirror>of(qualifierAnnotations.iterator().next());
    default:
        throw new IllegalArgumentException(e + " was annotated with more than one @Qualifier annotation");
    }
}

From source file:com.android.camera.one.v2.Camera2OneCameraManagerImpl.java

/**
 * Create a new camera2 api hardware manager.
 *//*  w  w w  .  j  ava2 s.  c o m*/
public static Optional<Camera2OneCameraManagerImpl> create() {
    if (!ApiHelper.HAS_CAMERA_2_API) {
        return Optional.absent();
    }
    CameraManager cameraManager;
    try {
        cameraManager = AndroidServices.instance().provideCameraManager();
    } catch (IllegalStateException ex) {
        Log.e(TAG, "camera2.CameraManager is not available.");
        return Optional.absent();
    }
    Camera2OneCameraManagerImpl hardwareManager = new Camera2OneCameraManagerImpl(cameraManager);
    return Optional.of(hardwareManager);
}

From source file:com.google.template.soy.jbcsrc.BytecodeCompiler.java

/**
 * Compiles all the templates in the given registry.
 *
 * @return CompiledTemplates or {@code absent()} if compilation fails, in which case errors will
 *     have been reported to the error reporter.
 *///from w  ww  .  j ava  2 s .c  o  m
public static Optional<CompiledTemplates> compile(TemplateRegistry registry, ErrorReporter reporter) {
    ErrorReporter.Checkpoint checkpoint = reporter.checkpoint();
    checkForUnsupportedFeatures(registry, reporter);
    if (reporter.errorsSince(checkpoint)) {
        return Optional.absent();
    }
    CompiledTemplateRegistry compilerRegistry = new CompiledTemplateRegistry(registry);

    // TODO(lukes): currently we compile all the classes, but you could easily imagine being
    // configured in such a way that we load the classes from the system class loader.  Then we
    // could add a build phase that writes the compiled templates out to a jar.  Then in the non
    // development mode case we could skip even parsing templates!
    MemoryClassLoader loader = compileTemplates(registry, compilerRegistry, reporter);
    if (reporter.errorsSince(checkpoint)) {
        return Optional.absent();
    }
    ImmutableMap.Builder<String, CompiledTemplate.Factory> factories = ImmutableMap.builder();
    for (TemplateNode node : registry.getAllTemplates()) {
        String name = node.getTemplateName();
        factories.put(name, loadFactory(compilerRegistry.getTemplateInfo(name), loader));
    }
    return Optional.of(new CompiledTemplates(factories.build()));
}

From source file:net.awairo.mcmod.spawnchecker.client.common.Refrection.java

/**
 * ??????????.//from  w w w . j  a  va2 s  .  c o m
 * 
 * @return ??.
 */
public static Optional<InetSocketAddress> getServerAddress() {
    checkState(GAME.theWorld != null, "world is not started");
    checkState(GAME.getIntegratedServer() == null, "current mode is the single player.");

    final NetHandlerPlayClient sendQueue = getFieldValue(WorldClient.class, GAME.theWorld, "sendQueue",
            ConstantsConfig.instance().sendQueueSrgName);

    if (sendQueue == null)
        return Optional.absent();

    final NetworkManager netManager = sendQueue.getNetworkManager();

    if (netManager.getSocketAddress() instanceof InetSocketAddress)
        return Optional.fromNullable((InetSocketAddress) netManager.getSocketAddress());

    if (LOGGER.isDebugEnabled() && netManager.getSocketAddress() != null)
        LOGGER.debug(netManager.getSocketAddress().getClass().getName());

    LOGGER.warn("not found InetSocketAddress");

    return Optional.absent();
}

From source file:com.complexible.common.base.Reflect.java

/**
 * Returns the class with the given name.  A ClassNotFoundException will not be thrown if
 * the class does not exist, an {@link com.google.common.base.Optional} with an absent value will be returned instead.
 * Similarly, if a ClassCastException is thrown, because the class name is valid, but is
 * not of the correct type of class requested by the user, an Optional without a value will be returned..
 *
 * @param theClassName   the class name/*from w ww.  j a v a  2 s.c om*/
 * @return            the class, or null if it does not exist
 */
public static <T> Optional<Class<T>> getClass(final String theClassName) {
    try {
        return Optional.of((Class<T>) Class.forName(theClassName));
    } catch (ClassNotFoundException e) {
        return Optional.absent();
    } catch (ClassCastException e) {
        return Optional.absent();
    }
}

From source file:org.opendaylight.yangtools.yang.data.impl.schema.tree.DeleteLeafCandidateNode.java

@Override
@Nonnull
public Optional<NormalizedNode<?, ?>> getDataAfter() {
    return Optional.absent();
}

From source file:gobblin.data.management.copy.watermark.CopyableFileWatermarkHelper.java

/**
 * Get Optional {@link CopyableFileWatermarkGenerator} from {@link State}.
 *///from w  ww . j  a va 2 s.  c om
public static Optional<CopyableFileWatermarkGenerator> getCopyableFileWatermarkGenerator(State state)
        throws IOException {
    try {
        if (state.contains(WATERMARK_CREATOR)) {
            Class<?> watermarkCreatorClass = Class.forName(state.getProp(WATERMARK_CREATOR));
            return Optional.of((CopyableFileWatermarkGenerator) watermarkCreatorClass.newInstance());
        } else {
            return Optional.absent();
        }
    } catch (ClassNotFoundException | InstantiationException | IllegalAccessException e) {
        throw new IOException("Failed to instantiate watermarkCreator.");
    }
}