connecters in activemq

ActiveMQ Messaging Services

Using ActiveMQ Why and When ActiveMQ was meant to be used as the JMS spec intended for remote communications

between distributed applications

ActiveMQ is used in the environment where applications need to overcome the agenda of tight

coupling

Asynchronous calls can be made easy in the loosely coupled applications ie Just fire and forget

No need to worry about how the application will handle the calls

Message is send to MOM() in a one-way fashion

When To Use ActiveMQ

Heterogeneous Application Integration

ActiveMQ is a tool with cross-language capabilities Basically it is an ActiveMQ broker is written in java

so it basically provides a Java client naturally But other than that it also provides a multi language client

support like c c++ NET Pearl PHP and many more

Loosen Couple between applications

Previously applications with RPC were believed to be very safe as message transmission and its

conformation plays a vital role in it But ActiveMQ change the acceptance of asynchronous scenario ie

one just need to send the message and need not to worry about it retrieval This decreases its

interdependency and makes it more loosely coupled and flexible That saves much of time over

interdependent systems Components use fire and forget kind of mechanism

Event Driven Architecture

The decoupled asynchronous style of architecture described allows broker itself to manage many clients

via tuning additional memory location and so on (known Vertical Scalability) Instead of rely on adding

number of broker nodes relying upon adding and handling the clients

Features of ActiveMQ

Active MQ is messaging service used for communication over various platforms ActivceMQ has

following features

JMS Compliance

ActiveMQ is an implementation of JMS 11 spec JMS provide guaranties like synchronous and

Asynchronous Messaging services once and once only message delivery message durability for

subscribers and more

Connectivity

It provides a wide range of support to protocol like Https Ip multicast SSL STOMP TCP UDP

XMPP and more Support to such wide range protocol increases its usability

Integration with application servers and Secured

ActiveMQ is much flexible as it provides a wide integration for application servers Also for security it

provides JAAS login modules and uses property files for authorization and authentication

Various client API

It provides a various client support for languages other than Java like cc++ NET Pearl PHP

Python Ruby and more

Clustering

Many ActiveMQ tools can provide a powerful set of features such as working of many ActiveMQ brokers

together that forms federated network of brokers

Dramatically Simplified Administration

ActiveMQ after years of monitoring provides a simplified administration tool for control of messages

This administration tool is so simple to look after that no extra resource is allocated for it

Understanding Message-oriented Middleware Message Oriented Middleware has played an important role in software communication in

asynchronous loosely-coupled reliable scalable and secure manner among distributed applications

MOMrsquos are acting as a message mediator between Message senders and receivers At high level

messages are business information that are transferred from sender to receiver using MOM that are

known as destinations

Both sender and receiver need not to get connected at same time MOM takes the message from sender

and sends to relevant receiver based on its destination address based on the availability of that user

This is how MOM helps in achieving loose-coupling And this is what recommended as asynchronous

messaging

Also the beneficiary part of MOM is that it provides a wide support to protocols HTTPS multicast SSL

TCPIP UDP and more

Java Messaging Services (JMS)

Java Messaging services is an API that is developed using Java client but still hides the complexity and

supports many other clients for implementations Like NET Ruby Pearl PHP etc

JMS provided many artifacts in world of messaging like

JMS Client [Pure Java client implementation]

NON-JMS Client [App written using Native JMS client]

JMS Producer [Client app that creates and sends JMS messages]

JMS Consumer [Client app that receives and processes JMS messages]

JMS Provider [Implementation interface in Java]

JMS Message

JMS Domains [P2P and publishSubscribe]

Java Message in JMS is made of 2 following things

Headers

o JMSCorrelationID o JMSDeliveryMode o JMSDestination o JMSExpiration o JMSMessageID o JMSPriority o JMSRedelivered o JMSReployTo o JMSTimestamp o JMSType

Payload

o It is just the content of the message the actual content

JMS Message Properties

JMSXAppIDmdashIdentifies the application sending the message

JMSXConsumerTXIDmdashThe transaction identifier for the transaction within which this message was consumed

JMSXDeliveryCountmdashThe number of message delivery attempts

JMSXGroupIDmdashThe message group of which this message is a part

JMSXGroupSeqmdashThe sequence number of this message within the group

JMSXProducerTXIDmdashThe transaction identifier for the transaction within which

this message was produced

JMSXRcvTimestampmdashThe time the JMS provider delivered the message to the consumer

JMSXStatemdashUsed to define a provider-specific state

JMSXUserID mdashIdentifies the user sending the message

JMS Message Body

MessagemdashThe base message type Used to send a message with no payload only headers and properties Typically used for simple event notification

TextMessage mdashA message whose payload is a String Commonly used to send simple textual and XML data

MapMessage mdashUses a set of namevalue pairs as its payload The names are of type String and the values are a Java primitive type

BytesMessage mdashUsed to contain an array of uninterrupted bytes as the payload

StreamMessagemdashA message with a payload containing a stream of primitive Java types thatrsquos filled and read sequentially

ObjectMessagemdashUsed to hold a serializable Java object as its payload Usually used for complex Java objects Also supports Java collections

JMS Domains

Persistent

Non-Persistent

Java Messaging Application Creation Steps

1 Acquire a JMS connection factory 2 Create a JMS connection using the connection factory 3 Start the JMS connection 4 Create a JMS session from the connection 5 Acquire a JMS destination 6 Create a JMS producer OR a Create a JMS producer b Create a JMS message and address it to a destination 7 Create a JMS consumer a Create a JMS consumer b Optionally register a JMS message listener 8 Send or receive JMS message(s) 9 Close all JMS resources (connection session producer consumer and so forth)

ActiveMQ Connectors

Understanding Connector URI

Itrsquos a compact string of characters that are used to refer a resource

Basically every URI has a following string resource ltschemegtltscheme-specific-partgt for ex

mailtoabcactivemqapacheorg

Where mailto ndash is scheme and Scheme-Specific-Part is the actual mail address

As we saw in previous examples that tcplocalhost61616trace=true ActiveMQ comes with the

concept of composite URI A composite URI automatically reconnects to another URI over failure of first

resource URI Ex static(tcphost161616tcphost261616)

HERE ABOVE STATIC IS lsquoSCHEMErsquo AND THERE ARE TWO PATHS

Note- White Space are not supported in composite URI

Transport Connectors

Transport connectors are used to send messages and receive messages fromto broker

Configuring Transport Connectors

Let us take that same portfolio example take a look at ActiveMQ demo configuration file

(confactivemq-demoxml)

lttransportConnectorsgt

lttransport-connector name=openwire uri=rdquotcplocalhost61616rdquogt

lttransportConnector name=ssl uri=ssllocalhost61617gt

lttransportConnector name=stomp uri=stomplocalhost61613gt

lttransportConnector name=xmpp uri=xmpplocalhost61222gt


Following code should be enough to get on transport connectors

ActiveMQConnectionFactory factory =

new ActiveMQConnectionFactory(tcplocalhost61616)

Connection connection = factorycreateConnection()

connectionstart()

Session session =

connectioncreateSession(false SessionAUTO_ACKNOWLEDGE)

Protocols

TCP [Transmission Control Protocol]

TCP has its own benefits of transferring data over peer to peer over years of long time we are relying on

TCP for successfully and securely sending data over Network

In TCP for sending messages in JMS we need to serialize messages in an suitable form ie They must be

serialized in and out as byte sequence to be sent over the wire protocol The default protocol used in

ActiveMQ is wire protocol

Syntax

Tcphostnameportkey=valueampkey=value

The following snippet of code needs to be added into the default configuration


lttransportConnector name=tcprdquo uri=tcplocalhost61616trace=truegt


mvn execjava -DexecmainClass=orgapacheactivemqbookch4Consumer -

Dexecargs=tcplocalhost61616 CSCO ORCL

Benefits of TCP

Efficiency

Since TCP uses open wire protocol for converting and receiving bytes over network It is very

efficient in terms of usage and performance

Reliability

Messages wonrsquot be lost over network

NIO [New IO Api Protocol]

New Input Output connector is not the replacement of traditional Java IO library It was an alternative

approach to network programming and access to some low-level IO operations of modern operating

systems

In all NIO is same as TCP the only difference is in its implementation TCP uses internally openwire that

makes it more secure and is implemented using transport API where as NIO connector is implemented

using NIO API

When there are so many clients wants to get connected to broker and the system may feel like

completely overloaded from clients at that moment NIO protocol can be used

Syntax

niohostnameportkey=value

Example [Add to the default configuration] ie confactivemqxml


lttransportConnector name=tcp uri=tcplocalhost61616trace=true gt

lttransportConnector name=nio uri=niolocalhost61618trace=true gt


Note - NIO connector must not set on the client side as it is server specific client needs to use TCP and

since server needs to maintain load and other issues we need to use NIO at server side

Letrsquos simply execute the example using following steps

Step 1

Goto confactivemqxml

Step 2

Add the Following lines in the lttransportconnectorsgt


Step 3

Restart ActiveMQ Server

Step 4

Execute Publisher [mvn execjava -DexecmainClass=orgapacheactivemqbookch4Publisher

-Dexecargs=niolocalhost61618 CSCO ORCL]

Step 5

Execute Consumer [mvn execjava -DexecmainClass=orgapacheactivemqbookch4Consumer

-Dexecargs=tcplocalhost61616 CSCO ORCL]

Just look at this issue will help a lot in getting the beneath of

lsquohttpactivemq2283324n4nabblecomProblem-with-NIO-protocol-td3540710htmlrsquo

UDP [User Datagram Protocol]

UDP was designed basically for faster transmission of data over network Situations where the

transferring of data is more important than its reliability in such cases UDP is preferable [Voip Online

Gaming]

Syntax

udphostnameportkey=value

Example Add following code lines to execute this UDP example

Edit [confactivemqxml]

lttransportconnectorsgt

lttransportConnector name=udp uri=udplocalhost61618trace=true gt



Step 1


Step 2



Step 3


Step 4


-Dexecargs=udplocalhost61618 CSCO ORCL]

Step 5



IT completely depends on the user which protocol needs to be used

SSL [Secure Socket Layer]

In situations where security is more concern that transmission SSL is a secure protocol need to be used

in such situations It internally uses the TCP so it covers all the basic TCP properties apart from it it

encrypts the data on TCP channel makes it more secure

It uses SSL transport connector that adds an SSL layer over TCP It provides an encrypted communication

over client and brokers

Syntax

sslhostnameportkey=value

Example Add following code lines to execute this SSL example



lttransportConnector name=ssl uri=ssllocalhost61617trace=true gt


Here executing example covers some extra steps since we need to create certificates (keystores) for the

client

Step 1


Step 2



Step 3


Step 4


-Dexecargs=ssllocalhost61617 CSCO ORCL] =gt Gives Error

Note - To resolve this error we need to provide some basic system properties

javaxnetsslkeyStoremdashDefines which keystore the client should use

javaxnetsslkeyStorePasswordmdashDefines an appropriate password for the keystore

javaxnetssltrustStoremdashDefines an appropriate truststore the client should use

Step 4

Execute Following Command for Publisher

mvn -DjavaxnetsslkeyStore=$ACTIVEMQ_HOMEconfclientks -

DjavaxnetsslkeyStorePassword=password -

DjavaxnetssltrustStore=$ACTIVEMQ_HOMEconfclientts execjava -

DexecmainClass=orgapacheactivemqbookch4Publisher -Dexecargs=ssllocalhost61617 CSCO

ORCL

Step 5

Execute Following Command for Consumer



DjavaxnetssltrustStore=$ACTIVEMQ_HOMEconfclientts execjava

DexecmainClass=orgapacheactivemqbookch4Consumer -Dexecargs=ssllocalhost61617 CSCO

ORCL

It basically needs two types stored keys and certificates The first so called is keystore(brokerks) and the

another is truststore (brokerts)

Note - You can also enable and disable the SSL ciphers

ACTIVEMQ_HOMEconfactivemqxml

Add Following Lines of Code


lttransportConnector

name=ssl uri=ssllocalhost61617transportenabledCipherSuites=SSL_RSA_WITH_RC4_128_SHA

gt


Hypertext Transfer Protocol [HttpHttps]

Systems where firewalls are configured to allow basic services such as web access and email In those

scenarios ActiveMQ comes into existence

ActiveMQ implements the HTTP Transport connector which provides the xml formatted data to broker

using HTTP Protocol

Syntax HTTP HTTPS

httphostnameportkey=value

httpshostnameportkey=value




lttransportConnector name=tcp uri=tcplocalhost61616trace=truegt

lttransportConnector name=http uri=httplocalhost8080trace=true gt


Note- Basically there are two transports that are listening to port 8080 TCP transport and HTTP

Transport

ltdependencygt

ltgroupIdgtorgapacheactivemqltgroupIdgt

ltartifactIdgtactivemq-optionalltartifactIdgt

ltversiongt541ltversiongt

ltdependencygt

ActiveMQ is an implementation of JMS 11 spec JMS provide guaranties like synchronous and

Asynchronous Messaging services once and once only message delivery message durability for

subscribers and more

Connectivity

It provides a wide range of support to protocol like Https Ip multicast SSL STOMP TCP UDP

XMPP and more Support to such wide range protocol increases its usability

Integration with application servers and Secured

ActiveMQ is much flexible as it provides a wide integration for application servers Also for security it

provides JAAS login modules and uses property files for authorization and authentication

Various client API

It provides a various client support for languages other than Java like cc++ NET Pearl PHP

Python Ruby and more

Clustering

Many ActiveMQ tools can provide a powerful set of features such as working of many ActiveMQ brokers

together that forms federated network of brokers

Dramatically Simplified Administration

ActiveMQ after years of monitoring provides a simplified administration tool for control of messages

This administration tool is so simple to look after that no extra resource is allocated for it

Understanding Message-oriented Middleware Message Oriented Middleware has played an important role in software communication in

asynchronous loosely-coupled reliable scalable and secure manner among distributed applications

MOMrsquos are acting as a message mediator between Message senders and receivers At high level

messages are business information that are transferred from sender to receiver using MOM that are

known as destinations

Both sender and receiver need not to get connected at same time MOM takes the message from sender

and sends to relevant receiver based on its destination address based on the availability of that user

This is how MOM helps in achieving loose-coupling And this is what recommended as asynchronous

messaging

Also the beneficiary part of MOM is that it provides a wide support to protocols HTTPS multicast SSL

TCPIP UDP and more










JMS Message



Headers


Payload













JMS Message Body







JMS Domains

Persistent

Non-Persistent



ActiveMQ Connectors


























connectionstart()

Session session =


Protocols







Syntax








Benefits of TCP

Efficiency



Reliability





systems



using NIO API



Syntax










Step 1


Step 2



Step 3


Step 4



Step 5








Gaming]

Syntax








Step 1


Step 2



Step 3


Step 4



Step 5










Syntax








client

Step 1


Step 2



Step 3


Step 4







Step 4






ORCL

Step 5






ORCL









gt






using HTTP Protocol

Syntax HTTP HTTPS










Transport

ltdependencygt




ltdependencygt










JMS Message



Headers


Payload













JMS Message Body







JMS Domains

Persistent

Non-Persistent



ActiveMQ Connectors


























connectionstart()

Session session =


Protocols







Syntax








Benefits of TCP

Efficiency



Reliability





systems



using NIO API



Syntax










Step 1


Step 2



Step 3


Step 4



Step 5








Gaming]

Syntax








Step 1


Step 2



Step 3


Step 4



Step 5










Syntax








client

Step 1


Step 2



Step 3


Step 4







Step 4






ORCL

Step 5






ORCL









gt






using HTTP Protocol

Syntax HTTP HTTPS










Transport

ltdependencygt




ltdependencygt





JMS Message Body







JMS Domains

Persistent

Non-Persistent



ActiveMQ Connectors


























connectionstart()

Session session =


Protocols







Syntax








Benefits of TCP

Efficiency



Reliability





systems



using NIO API



Syntax










Step 1


Step 2



Step 3


Step 4



Step 5








Gaming]

Syntax








Step 1


Step 2



Step 3


Step 4



Step 5










Syntax








client

Step 1


Step 2



Step 3


Step 4







Step 4






ORCL

Step 5






ORCL









gt






using HTTP Protocol

Syntax HTTP HTTPS










Transport

ltdependencygt




ltdependencygt

ActiveMQ Connectors


























connectionstart()

Session session =


Protocols







Syntax








Benefits of TCP

Efficiency



Reliability





systems



using NIO API



Syntax










Step 1


Step 2



Step 3


Step 4



Step 5








Gaming]

Syntax








Step 1


Step 2



Step 3


Step 4



Step 5










Syntax








client

Step 1


Step 2



Step 3


Step 4







Step 4






ORCL

Step 5






ORCL









gt






using HTTP Protocol

Syntax HTTP HTTPS










Transport

ltdependencygt




ltdependencygt


connectionstart()

Session session =


Protocols







Syntax








Benefits of TCP

Efficiency



Reliability





systems



using NIO API



Syntax










Step 1


Step 2



Step 3


Step 4



Step 5








Gaming]

Syntax








Step 1


Step 2



Step 3


Step 4



Step 5










Syntax








client

Step 1


Step 2



Step 3


Step 4







Step 4






ORCL

Step 5






ORCL









gt






using HTTP Protocol

Syntax HTTP HTTPS










Transport

ltdependencygt




ltdependencygt





systems



using NIO API



Syntax










Step 1


Step 2



Step 3


Step 4



Step 5








Gaming]

Syntax








Step 1


Step 2



Step 3


Step 4



Step 5










Syntax








client

Step 1


Step 2



Step 3


Step 4







Step 4






ORCL

Step 5






ORCL









gt






using HTTP Protocol

Syntax HTTP HTTPS










Transport

ltdependencygt




ltdependencygt

Step 3


Step 4



Step 5








Gaming]

Syntax








Step 1


Step 2



Step 3


Step 4



Step 5










Syntax








client

Step 1


Step 2



Step 3


Step 4







Step 4






ORCL

Step 5






ORCL









gt






using HTTP Protocol

Syntax HTTP HTTPS










Transport

ltdependencygt




ltdependencygt


Step 2



Step 3


Step 4



Step 5










Syntax








client

Step 1


Step 2



Step 3


Step 4







Step 4






ORCL

Step 5






ORCL









gt






using HTTP Protocol

Syntax HTTP HTTPS










Transport

ltdependencygt




ltdependencygt





client

Step 1


Step 2



Step 3


Step 4







Step 4






ORCL

Step 5






ORCL









gt






using HTTP Protocol

Syntax HTTP HTTPS










Transport

ltdependencygt




ltdependencygt

Step 5






ORCL









gt






using HTTP Protocol

Syntax HTTP HTTPS










Transport

ltdependencygt




ltdependencygt









Transport

ltdependencygt




ltdependencygt

connecters in activemq

Documents