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:org.code_house.ebus.common.BasicCodecRegistry.java

@Override
public <T, R> Optional<CommandCodec<T, R>> find(Command<T, R> command) {
    if (codecs.containsKey(command)) {
        return Optional.of(codecs.get(command));
    }//  w w  w .j ava2 s.  c o m
    return Optional.absent();
}

From source file:org.apache.druid.tasklogs.NoopTaskLogs.java

@Override
public Optional<ByteSource> streamTaskLog(String taskid, long offset) {
    return Optional.absent();
}

From source file:com.addthis.hydra.job.spawn.jersey.DefaultAuthenticator.java

@Override
public Optional<User> authenticate(BasicCredentials credentials) throws AuthenticationException {
    if (!StringUtils.isEmpty(credentials.getUsername())) {
        return Optional.of(new User(credentials.getUsername(), credentials.getUsername(), true)); //default admin
    }/* w ww . jav  a2s.co  m*/
    return Optional.absent();
}

From source file:com.facebook.buck.util.concurrent.AssertScopeExclusiveAccess.java

public AssertScopeExclusiveAccess() {
    inScope = new AtomicBoolean();
    inScopeStack = Optional.absent();
}

From source file:io.crate.sql.tree.KillStatement.java

public KillStatement() {
    this.jobId = Optional.absent();
}

From source file:org.geogit.api.plumbing.ResolveBranchId.java

@Override
public Optional<Ref> call() {
    Preconditions.checkState(id != null, "id has not been set.");
    Predicate<Ref> filter = new Predicate<Ref>() {
        @Override//from  w ww .ja va 2 s.co  m
        public boolean apply(@Nullable Ref ref) {
            return ref.getObjectId().equals(id);
        }
    };
    ImmutableSet<Ref> refs = command(ForEachRef.class).setFilter(filter).call();
    if (refs.isEmpty()) {
        return Optional.absent();
    } else {
        return Optional.of(refs.iterator().next());
    }
}

From source file:org.knight.examples.guava.basic.UsingAvoidingNullExamples.java

public void run() {
    Optional<String> o1 = Optional.of("Guava-library");
    if (o1.isPresent()) {
        log("o1: " + o1.get());
    } else {/*from   www. j  av a 2  s  . c o m*/
        log("o1: " + o1.toString());
    }

    Optional<String> o2 = Optional.absent();
    try {
        //will cause a IllegalStateException
        log("o2: " + o2.get());
    } catch (IllegalStateException e) {
        log("o2 is absent, use get() will cause a IllegalStateException.");
    }

    Optional<String> o3 = Optional.fromNullable(null);
    log("o3 present = " + o3.isPresent());
    try {
        //will cause a IllegalStateException
        log("o3: " + o3.get());
    } catch (IllegalStateException e) {
        log("o3 is absent, use get() will cause a IllegalStateException.");
    }
    if (o3.orNull() == null) {
        log("o3 is absent, so orNull() returns null.");
    }

    Optional<String> o4 = Optional.fromNullable("Hello World");
    log("o4: " + o4.or("o4 is present, so this default value will not be printed."));

    Optional<Book> o5 = Optional.of(Book.generateBook());
    log("o5: " + o5.get().toString());
}

From source file:org.onos.yangtools.yang.data.api.schema.tree.spi.ValueNode.java

@Override
public Optional<TreeNode> getChild(final PathArgument childId) {
    LOG.warn("Attempted to access child {} of value-node {}", childId, this);
    return Optional.absent();
}

From source file:com.dowdandassociates.gentoo.bootstrap.InstanceUtils.java

public static Optional<Instance> onDemandInstance(AmazonEC2 ec2Client, Optional<Image> image, Integer minCount,
        Integer maxCount, SecurityGroupInformation securityGroupInformation,
        KeyPairInformation keyPairInformation, Optional<String> instanceType, Optional<String> availabilityZone,
        Long sleep) {//  w  w  w .  j a  va  2s  . c o m
    if (!image.isPresent()) {
        return Optional.absent();
    }

    RunInstancesRequest runInstancesRequest = new RunInstancesRequest().withImageId(image.get().getImageId())
            .withMinCount(minCount).withMaxCount(maxCount)
            .withSecurityGroups(securityGroupInformation.getGroupName())
            .withKeyName(keyPairInformation.getName());

    log.info("ImageId=" + image.get().getImageId());
    log.info("MinCount=" + minCount);
    log.info("MaxCount=" + maxCount);
    log.info("SecurityGroups.1=" + securityGroupInformation.getGroupName());
    log.info("KeyName=" + keyPairInformation.getName());

    if (instanceType.isPresent()) {
        runInstancesRequest.setInstanceType(instanceType.get());
        log.info("InstanceType=" + instanceType.get());
    }

    if (availabilityZone.isPresent()) {
        runInstancesRequest.setPlacement(new Placement().withAvailabilityZone(availabilityZone.get()));

        log.info("Placement.AvailabilityZone=" + availabilityZone.get());
    }

    RunInstancesResult runInstancesResult = ec2Client.runInstances(runInstancesRequest);

    DescribeInstanceStatusRequest describeInstanceStatusRequest = new DescribeInstanceStatusRequest()
            .withInstanceIds(runInstancesResult.getReservation().getInstances().get(0).getInstanceId());

    try {
        while (true) {
            log.info("Sleeping for " + sleep + " ms");
            Thread.sleep(sleep);

            DescribeInstanceStatusResult describeInstanceStatusResult = ec2Client
                    .describeInstanceStatus(describeInstanceStatusRequest);
            if (describeInstanceStatusResult.getInstanceStatuses().isEmpty()) {
                continue;
            }
            InstanceStatus instance = describeInstanceStatusResult.getInstanceStatuses().get(0);

            String instanceState = instance.getInstanceState().getName();

            log.info("instanceState = " + instanceState);

            if ("pending".equals(instanceState)) {
                continue;
            }

            if (!"running".equals(instanceState)) {
                return Optional.absent();
            }

            String instanceStatus = instance.getInstanceStatus().getStatus();
            String systemStatus = instance.getSystemStatus().getStatus();

            log.info("instanceStatus = " + instanceStatus);
            log.info("systemStatus = " + systemStatus);

            if ("impaired".equals(instanceStatus)) {
                return Optional.absent();
            }

            if ("impaired".equals(systemStatus)) {
                return Optional.absent();
            }

            if (!"ok".equals(instanceStatus)) {
                continue;
            }

            if (!"ok".equals(systemStatus)) {
                continue;
            }

            break;
        }
    } catch (InterruptedException e) {
        return Optional.absent();
    }

    DescribeInstancesResult describeInstancesResult = ec2Client.describeInstances(new DescribeInstancesRequest()
            .withInstanceIds(runInstancesResult.getReservation().getInstances().get(0).getInstanceId()));

    return Optional.fromNullable(describeInstancesResult.getReservations().get(0).getInstances().get(0));
}

From source file:org.fabrician.enabler.util.RunCmdAuxiliaryOptions.java

public static Optional<String> build(RuntimeContextVariable var) {
    try {// ww  w.j a va  2  s .  com
        RunCmdAuxiliaryOptions val = valueOf(var.getName());
        if (var.getTypeInt() != RuntimeContextVariable.OBJECT_TYPE) {
            String currentValue = StringUtils.trimToEmpty((String) var.getValue());
            // empty value means the option is not valid and would be skipped
            // so that we accept the default
            if (!currentValue.isEmpty()) {
                if (val.isBooleanType) {
                    Boolean b = BooleanUtils.toBooleanObject(currentValue);
                    if (b != val.defaultBooleanValue) {
                        return Optional.of(" " + val.optionSwitch + " ");
                    }
                } else {
                    return Optional.of(" " + val.optionSwitch + " " + currentValue);
                }
            }
        }

    } catch (Exception ex) {

    }
    return Optional.absent();
}