com.azure.messaging.eventhubs

Class EventHubClientBuilder

java.lang.Object

com.azure.messaging.eventhubs.EventHubClientBuilder

public class EventHubClientBuilder
extends Object

This class provides a fluent builder API to aid the instantiation of EventHubProducerAsyncClient, EventHubProducerClient, EventHubConsumerAsyncClient, and EventHubConsumerClient. Calling any of the .build*Client() methods will create an instance of the respective client.

Credentials are required to perform operations against Azure Event Hubs. They can be set by using one of the following methods:

• connectionString(String) with a connection string to a specific Event Hub.
• connectionString(String, String) with an Event Hub namespace connection string and the Event Hub name.
• credential(String, String, TokenCredential) with the fully qualified namespace, Event Hub name, and a set of credentials authorized to use the Event Hub.

In addition, consumer group is required when creating EventHubConsumerAsyncClient or EventHubConsumerClient.

Creating an asynchronous EventHubProducerAsyncClient using Event Hubs namespace connection string

In the sample, the namespace connection string is used to create an asynchronous Event Hub producer. Notice that "EntityPath" is not a component in the connection string.

// The required parameter is a way to authenticate with Event Hubs using credentials.
// The connectionString provides a way to authenticate with Event Hub.
EventHubProducerAsyncClient producer = new EventHubClientBuilder()
    .connectionString(
        "Endpoint={fully-qualified-namespace};SharedAccessKeyName={policy-name};SharedAccessKey={key}",
        "event-hub-name")
    .buildAsyncProducerClient();

Creating a synchronous EventHubConsumerClient using an Event Hub instance connection string

In the sample, the namespace connection string is used to create a synchronous Event Hub consumer. Notice that "EntityPath" is in the connection string.

// The required parameters are `consumerGroup`, and a way to authenticate with Event Hubs using credentials.
EventHubConsumerClient consumer = new EventHubClientBuilder()
    .connectionString(
        "Endpoint={eh-namespace};SharedAccessKeyName={policy-name};SharedAccessKey={key};Entity-Path={hub-name}")
    .consumerGroup("$DEFAULT")
    .buildConsumerClient();

Creating producers and consumers that share the same connection

By default, a dedicated connection is created for each producer and consumer created from the builder. If users wish to use the same underlying connection, they can toggle shareConnection().

// Toggling `shareConnection` instructs the builder to use the same underlying connection
// for each consumer or producer created using the same builder instance.
EventHubClientBuilder builder = new EventHubClientBuilder()
    .connectionString("event-hubs-instance-connection-string")
    .shareConnection();

// Both the producer and consumer created share the same underlying connection.
EventHubProducerAsyncClient producer = builder.buildAsyncProducerClient();
EventHubConsumerAsyncClient consumer = builder
    .consumerGroup("my-consumer-group")
    .buildAsyncConsumerClient();

See Also:

EventHubProducerAsyncClient, EventHubProducerClient, EventHubConsumerAsyncClient, EventHubConsumerClient

Field Summary

Fields

Modifier and Type	Field and Description
static String	DEFAULT_CONSUMER_GROUP_NAME The name of the default consumer group in the Event Hubs service.

Constructor Summary

Constructors

Constructor and Description
EventHubClientBuilder() Creates a new instance with the default transport AmqpTransportType.AMQP and a non-shared connection.

Method Summary

Modifier and Type	Method and Description
EventHubConsumerAsyncClient	buildAsyncConsumerClient() Creates a new EventHubConsumerAsyncClient based on the options set on this builder.
EventHubProducerAsyncClient	buildAsyncProducerClient() Creates a new EventHubProducerAsyncClient based on options set on this builder.
EventHubConsumerClient	buildConsumerClient() Creates a new EventHubConsumerClient based on the options set on this builder.
EventHubProducerClient	buildProducerClient() Creates a new EventHubProducerClient based on options set on this builder.
EventHubClientBuilder	configuration(Configuration configuration) Sets the configuration store that is used during construction of the service client.
EventHubClientBuilder	connectionString(String connectionString) Sets the credential information given a connection string to the Event Hub instance.
EventHubClientBuilder	connectionString(String connectionString, String eventHubName) Sets the credential information given a connection string to the Event Hubs namespace and name to a specific Event Hub instance.
EventHubClientBuilder	consumerGroup(String consumerGroup) Sets the name of the consumer group this consumer is associated with.
EventHubClientBuilder	credential(String fullyQualifiedNamespace, String eventHubName, TokenCredential credential) Sets the credential information for which Event Hub instance to connect to, and how to authorize against it.
EventHubClientBuilder	prefetchCount(int prefetchCount) Sets the count used by the receiver to control the number of events the Event Hub consumer will actively receive and queue locally without regard to whether a receive operation is currently active.
EventHubClientBuilder	proxyOptions(ProxyOptions proxyOptions) Sets the proxy configuration to use for EventHubAsyncClient.
EventHubClientBuilder	retry(AmqpRetryOptions retryOptions) Sets the retry policy for EventHubAsyncClient.
EventHubClientBuilder	shareConnection() Toggles the builder to use the same connection for producers or consumers that are built from this instance.
EventHubClientBuilder	transportType(AmqpTransportType transport) Sets the transport type by which all the communication with Azure Event Hubs occurs.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

DEFAULT_CONSUMER_GROUP_NAME

public static final String DEFAULT_CONSUMER_GROUP_NAME

The name of the default consumer group in the Event Hubs service.

See Also:

Constant Field Values

Constructor Detail

EventHubClientBuilder

public EventHubClientBuilder()

Creates a new instance with the default transport AmqpTransportType.AMQP and a non-shared connection. A non-shared connection means that a dedicated AMQP connection is created for every Event Hub consumer or producer created using the builder.

Method Detail

connectionString

public EventHubClientBuilder connectionString(String connectionString)

Sets the credential information given a connection string to the Event Hub instance.

If the connection string is copied from the Event Hubs namespace, it will likely not contain the name to the desired Event Hub, which is needed. In this case, the name can be added manually by adding "EntityPath=EVENT_HUB_NAME" to the end of the connection string. For example, "EntityPath=telemetry-hub".

If you have defined a shared access policy directly on the Event Hub itself, then copying the connection string from that Event Hub will result in a connection string that contains the name.

Parameters:

connectionString - The connection string to use for connecting to the Event Hub instance. It is expected that the Event Hub name and the shared access key properties are contained in this connection string.

Returns:

The updated EventHubClientBuilder object.

Throws:

IllegalArgumentException - if connectionString is null or empty. Or, the connectionString does not contain the "EntityPath" key, which is the name of the Event Hub instance.

AzureException - If the shared access signature token credential could not be created using the connection string.

connectionString

public EventHubClientBuilder connectionString(String connectionString,
                                              String eventHubName)

Sets the credential information given a connection string to the Event Hubs namespace and name to a specific Event Hub instance.

Parameters:

connectionString - The connection string to use for connecting to the Event Hubs namespace; it is expected that the shared access key properties are contained in this connection string, but not the Event Hub name.

eventHubName - The name of the Event Hub to connect the client to.

Returns:

The updated EventHubClientBuilder object.

Throws:

NullPointerException - if connectionString or eventHubName is null.

IllegalArgumentException - if connectionString or eventHubName is an empty string. Or, if the connectionString contains the Event Hub name.

AzureException - If the shared access signature token credential could not be created using the connection string.

configuration

public EventHubClientBuilder configuration(Configuration configuration)

Sets the configuration store that is used during construction of the service client. If not specified, the default configuration store is used to configure the EventHubAsyncClient. Use Configuration.NONE to bypass using configuration settings during construction.

Parameters:

configuration - The configuration store used to configure the EventHubAsyncClient.

Returns:

The updated EventHubClientBuilder object.

shareConnection

public EventHubClientBuilder shareConnection()

Toggles the builder to use the same connection for producers or consumers that are built from this instance. By default, a new connection is constructed and used created for each Event Hub consumer or producer created.

Returns:

The updated EventHubClientBuilder object.

credential

public EventHubClientBuilder credential(String fullyQualifiedNamespace,
                                        String eventHubName,
                                        TokenCredential credential)

Sets the credential information for which Event Hub instance to connect to, and how to authorize against it.

Parameters:

fullyQualifiedNamespace - The fully qualified name for the Event Hubs namespace. This is likely to be similar to "{your-namespace}.servicebus.windows.net".

eventHubName - The name of the Event Hub to connect the client to.

credential - The token credential to use for authorization. Access controls may be specified by the Event Hubs namespace or the requested Event Hub, depending on Azure configuration.

Returns:

The updated EventHubClientBuilder object.

Throws:

IllegalArgumentException - if fullyQualifiedNamespace or eventHubName is an empty string.

NullPointerException - if fullyQualifiedNamespace, eventHubName, credentials is null.

proxyOptions

public EventHubClientBuilder proxyOptions(ProxyOptions proxyOptions)

Sets the proxy configuration to use for EventHubAsyncClient. When a proxy is configured, AmqpTransportType.AMQP_WEB_SOCKETS must be used for the transport type.

Parameters:

proxyOptions - The proxy configuration to use.

Returns:

The updated EventHubClientBuilder object.

transportType

public EventHubClientBuilder transportType(AmqpTransportType transport)

Sets the transport type by which all the communication with Azure Event Hubs occurs. Default value is AmqpTransportType.AMQP.

Parameters:

transport - The transport type to use.

Returns:

The updated EventHubClientBuilder object.

retry

public EventHubClientBuilder retry(AmqpRetryOptions retryOptions)

Sets the retry policy for EventHubAsyncClient. If not specified, the default retry options are used.

Parameters:

retryOptions - The retry policy to use.

Returns:

The updated EventHubClientBuilder object.

consumerGroup

public EventHubClientBuilder consumerGroup(String consumerGroup)

Sets the name of the consumer group this consumer is associated with. Events are read in the context of this group. The name of the consumer group that is created by default is "$Default".

Parameters:

consumerGroup - The name of the consumer group this consumer is associated with. Events are read in the context of this group. The name of the consumer group that is created by default is "$Default".

Returns:

The updated EventHubClientBuilder object.

prefetchCount

public EventHubClientBuilder prefetchCount(int prefetchCount)

Sets the count used by the receiver to control the number of events the Event Hub consumer will actively receive and queue locally without regard to whether a receive operation is currently active.

Parameters:

prefetchCount - The amount of events to queue locally.

Returns:

The updated EventHubClientBuilder object.

Throws:

IllegalArgumentException - if prefetchCount is less than 1 or greater than 8000.

buildAsyncConsumerClient

public EventHubConsumerAsyncClient buildAsyncConsumerClient()

Creates a new EventHubConsumerAsyncClient based on the options set on this builder. Every time buildAsyncConsumer() is invoked, a new instance of EventHubConsumerAsyncClient is created.

Returns:

A new EventHubConsumerAsyncClient with the configured options.

Throws:

IllegalArgumentException - If shared connection is not used and the credentials have not been set using either EventHubClientBuilder.connectionString(String) or EventHubClientBuilder.credential(String, String, TokenCredential). Also, if EventHubClientBuilder.consumerGroup(String) have not been set. And if a proxy is specified but the transport type is not web sockets.

buildConsumerClient

public EventHubConsumerClient buildConsumerClient()

Creates a new EventHubConsumerClient based on the options set on this builder. Every time buildConsumer() is invoked, a new instance of EventHubConsumerClient is created.

Returns:

A new EventHubConsumerClient with the configured options.

Throws:

IllegalArgumentException - If shared connection is not used and the credentials have not been set using either EventHubClientBuilder.connectionString(String) or EventHubClientBuilder.credential(String, String, TokenCredential). Also, if EventHubClientBuilder.consumerGroup(String) have not been set. And if a proxy is specified but the transport type is not web sockets.

buildAsyncProducerClient

public EventHubProducerAsyncClient buildAsyncProducerClient()

Creates a new EventHubProducerAsyncClient based on options set on this builder. Every time buildAsyncProducer() is invoked, a new instance of EventHubProducerAsyncClient is created.

Returns:

A new EventHubProducerAsyncClient instance with all the configured options.

Throws:

IllegalArgumentException - If shared connection is not used and the credentials have not been set using either EventHubClientBuilder.connectionString(String) or EventHubClientBuilder.credential(String, String, TokenCredential). Or, if a proxy is specified but the transport type is not web sockets.

buildProducerClient

public EventHubProducerClient buildProducerClient()

Creates a new EventHubProducerClient based on options set on this builder. Every time buildAsyncProducer() is invoked, a new instance of EventHubProducerClient is created.

Returns:

A new EventHubProducerClient instance with all the configured options.

Throws:

IllegalArgumentException - If shared connection is not used and the credentials have not been set using either EventHubClientBuilder.connectionString(String) or EventHubClientBuilder.credential(String, String, TokenCredential). Or, if a proxy is specified but the transport type is not web sockets.