JT400

Since Camel 1.5

Both producer and consumer are supported

The JT400 component allows you to exchange messages with an IBM i system using data queues, message queues, or program call. IBM i is the replacement for AS/400 and iSeries servers.

Maven users will need to add the following dependency to their pom.xml for this component:

<dependency>
    <groupId>org.apache.camel</groupId>
    <artifactId>camel-jt400</artifactId>
    <version>x.x.x</version>
    <!-- use the same version as your Camel core version -->
</dependency>

URI format

To send or receive data from a data queue

jt400://user:password@system/QSYS.LIB/LIBRARY.LIB/QUEUE.DTAQ[?options]

To send or receive messages from a message queue

jt400://user:password@system/QSYS.LIB/LIBRARY.LIB/QUEUE.MSGQ[?options]

To call program

jt400://user:password@system/QSYS.LIB/LIBRARY.LIB/program.PGM[?options]

Configuring Options

Camel components are configured on two separate levels:

  • component level

  • endpoint level

Configuring Component Options

The component level is the highest level which holds general and common configurations that are inherited by the endpoints. For example a component may have security settings, credentials for authentication, urls for network connection and so forth.

Some components only have a few options, and others may have many. Because components typically have pre configured defaults that are commonly used, then you may often only need to configure a few options on a component; or none at all.

Configuring components can be done with the Component DSL, in a configuration file (application.properties|yaml), or directly with Java code.

Configuring Endpoint Options

Where you find yourself configuring the most is on endpoints, as endpoints often have many options, which allows you to configure what you need the endpoint to do. The options are also categorized into whether the endpoint is used as consumer (from) or as a producer (to), or used for both.

Configuring endpoints is most often done directly in the endpoint URI as path and query parameters. You can also use the Endpoint DSL as a type safe way of configuring endpoints.

A good practice when configuring options is to use Property Placeholders, which allows to not hardcode urls, port numbers, sensitive information, and other settings. In other words placeholders allows to externalize the configuration from your code, and gives more flexibility and reuse.

The following two sections lists all the options, firstly for the component followed by the endpoint.

Component Options

The JT400 component supports 4 options, which are listed below.

Name Description Default Type

bridgeErrorHandler (consumer)

Allows for bridging the consumer to the Camel routing Error Handler, which mean any exceptions occurred while the consumer is trying to pickup incoming messages, or the likes, will now be processed as a message and handled by the routing Error Handler. By default the consumer will use the org.apache.camel.spi.ExceptionHandler to deal with exceptions, that will be logged at WARN or ERROR level and ignored.

boolean

lazyStartProducer (producer)

Whether the producer should be started lazy (on the first message). By starting lazy you can use this to allow CamelContext and routes to startup in situations where a producer may otherwise fail during starting and cause the route to fail being started. By deferring this startup to be lazy then the startup failure can be handled during routing messages via Camel’s routing error handlers. Beware that when the first message is processed then creating and starting the producer may take a little time and prolong the total processing time of the processing.

boolean

autowiredEnabled (advanced)

Whether autowiring is enabled. This is used for automatic autowiring options (the option must be marked as autowired) by looking up in the registry to find if there is a single instance of matching type, which then gets configured on the component. This can be used for automatic configuring JDBC data sources, JMS connection factories, AWS Clients, etc.

boolean

connectionPool (advanced)

Default connection pool used by the component. Note that this pool is lazily initialized. This is because in a scenario where the user always provides a pool, it would be wasteful for Camel to initialize and keep an idle pool.

AS400ConnectionPool

Endpoint Options

The JT400 endpoint is configured using URI syntax:

jt400:userID:password/systemName/objectPath.type

with the following path and query parameters:

Path Parameters (5 parameters)

Name Description Default Type

userID (security)

Required Returns the ID of the IBM i user.

String

password (security)

Required Returns the password of the IBM i user.

String

systemName (security)

Required Returns the name of the IBM i system.

String

objectPath (common)

Required Returns the fully qualified integrated file system path name of the target object of this endpoint.

String

type (common)

Required Whether to work with data queues or remote program call.

Enum values:

  • DTAQ

  • PGM

  • SRVPGM

  • MSGQ

Jt400Type

Query Parameters (33 parameters)

Name Description Default Type

ccsid (common)

Sets the CCSID to use for the connection with the IBM i system.

int

format (common)

Sets the data format for sending messages.

Enum values:

  • text

  • binary

Format

guiAvailable (common)

Sets whether IBM i prompting is enabled in the environment running Camel.

boolean

keyed (common)

Whether to use keyed or non-keyed data queues.

boolean

searchKey (common)

Search key for keyed data queues.

String

bridgeErrorHandler (consumer)

Allows for bridging the consumer to the Camel routing Error Handler, which mean any exceptions occurred while the consumer is trying to pickup incoming messages, or the likes, will now be processed as a message and handled by the routing Error Handler. By default the consumer will use the org.apache.camel.spi.ExceptionHandler to deal with exceptions, that will be logged at WARN or ERROR level and ignored.

boolean

messageAction (consumer)

Action to be taken on messages when read from a message queue. Messages can be marked as old (OLD), removed from the queue (REMOVE), or neither (SAME).

Enum values:

  • OLD

  • REMOVE

  • SAME

MessageAction

readTimeout (consumer)

Timeout in millis the consumer will wait while trying to read a new message of the data queue.

int

searchType (consumer)

Search type such as EQ for equal etc.

Enum values:

  • EQ

  • NE

  • LT

  • LE

  • GT

  • GE

SearchType

sendEmptyMessageWhenIdle (consumer)

If the polling consumer did not poll any files, you can enable this option to send an empty message (no body) instead.

boolean

sendingReply (consumer)

If true, the consumer endpoint will set the Jt400Constants.MESSAGE_REPLYTO_KEY header of the camel message for any IBM i inquiry messages received. If that message is then routed to a producer endpoint, the action will not be processed as sending a message to the queue, but rather a reply to the specific inquiry message.

boolean

exceptionHandler (consumer (advanced))

To let the consumer use a custom ExceptionHandler. Notice if the option bridgeErrorHandler is enabled then this option is not in use. By default the consumer will deal with exceptions, that will be logged at WARN or ERROR level and ignored.

ExceptionHandler

exchangePattern (consumer (advanced))

Sets the exchange pattern when the consumer creates an exchange.

Enum values:

  • InOnly

  • InOut

  • InOptionalOut

ExchangePattern

pollStrategy (consumer (advanced))

A pluggable org.apache.camel.PollingConsumerPollingStrategy allowing you to provide your custom implementation to control error handling usually occurred during the poll operation before an Exchange have been created and being routed in Camel.

PollingConsumerPollStrategy

lazyStartProducer (producer)

Whether the producer should be started lazy (on the first message). By starting lazy you can use this to allow CamelContext and routes to startup in situations where a producer may otherwise fail during starting and cause the route to fail being started. By deferring this startup to be lazy then the startup failure can be handled during routing messages via Camel’s routing error handlers. Beware that when the first message is processed then creating and starting the producer may take a little time and prolong the total processing time of the processing.

boolean

outputFieldsIdxArray (producer)

Specifies which fields (program parameters) are output parameters.

Integer[]

outputFieldsLengthArray (producer)

Specifies the fields (program parameters) length as in the IBM i program definition.

Integer[]

procedureName (producer)

Procedure name from a service program to call.

String

backoffErrorThreshold (scheduler)

The number of subsequent error polls (failed due some error) that should happen before the backoffMultipler should kick-in.

int

backoffIdleThreshold (scheduler)

The number of subsequent idle polls that should happen before the backoffMultipler should kick-in.

int

backoffMultiplier (scheduler)

To let the scheduled polling consumer backoff if there has been a number of subsequent idles/errors in a row. The multiplier is then the number of polls that will be skipped before the next actual attempt is happening again. When this option is in use then backoffIdleThreshold and/or backoffErrorThreshold must also be configured.

int

delay (scheduler)

Milliseconds before the next poll.

long

greedy (scheduler)

If greedy is enabled, then the ScheduledPollConsumer will run immediately again, if the previous run polled 1 or more messages.

boolean

initialDelay (scheduler)

Milliseconds before the first poll starts.

long

repeatCount (scheduler)

Specifies a maximum limit of number of fires. So if you set it to 1, the scheduler will only fire once. If you set it to 5, it will only fire five times. A value of zero or negative means fire forever.

long

runLoggingLevel (scheduler)

The consumer logs a start/complete log line when it polls. This option allows you to configure the logging level for that.

Enum values:

  • TRACE

  • DEBUG

  • INFO

  • WARN

  • ERROR

  • OFF

LoggingLevel

scheduledExecutorService (scheduler)

Allows for configuring a custom/shared thread pool to use for the consumer. By default each consumer has its own single threaded thread pool.

ScheduledExecutorService

scheduler (scheduler)

To use a cron scheduler from either camel-spring or camel-quartz component. Use value spring or quartz for built in scheduler.

Object

schedulerProperties (scheduler)

To configure additional properties when using a custom scheduler or any of the Quartz, Spring based scheduler.

Map

startScheduler (scheduler)

Whether the scheduler should be auto started.

boolean

timeUnit (scheduler)

Time unit for initialDelay and delay options.

Enum values:

  • NANOSECONDS

  • MICROSECONDS

  • MILLISECONDS

  • SECONDS

  • MINUTES

  • HOURS

  • DAYS

TimeUnit

useFixedDelay (scheduler)

Controls if fixed delay or fixed rate is used. See ScheduledExecutorService in JDK for details.

boolean

secured (security)

Whether connections to IBM i are secured with SSL.

boolean

Usage

When configured as a data queue consumer endpoint, the endpoint will poll a data queue on an IBM i system. For every entry on the data queue, a new Exchange is sent with the entry’s data in the In message’s body, formatted either as a String or a byte[], depending on the format. For a provider endpoint, the In message body contents will be put on the data queue as either raw bytes or text.

When configured as a message queue consumer endpoint, the endpoint will poll a message queue on an IBM i system. For every entry on the queue, a new Exchange is sent with the entry’s data in the In message’s body. The data is always formatted as a String. Note that only new messages will be processed. That is, any existing messages on the queue that have already been handled by another program will not be processed by this endpoint.

For a data queue provider endpoint, the In message body contents will be put on the data queue as either raw bytes or text.

For a message queue provider endpoint, the In message body contents are presumed to be text and sent to the queue as an informational message. Inquiry messages or messages requiring a message ID are not supported.

Connection pool

You can explicit configure a connection pool on the Jt400Component, or as an uri option on the endpoint.

Program call

This endpoint expects the input to be an Object[], whose object types are int, long, CharSequence (such as String), or byte[]. All other data types in the input array will be converted to String. For character inputs, CCSID handling is performed through the native jt400 library mechanisms. A parameter can be omitted by passing null as the value in its position (the program has to support it). After the program execution, the endpoint returns an Object[] in the message body. Depending on format, the returned array will be populated with byte[] or String objects representing the values as they were returned by the program. Input only parameters will contain the same data as the beginning of the invocation. This endpoint does not implement a provider endpoint!

Message headers

Consumer headers when consuming from data queues

The following headers are potentially available. If the values could not be determined, the headers will not be set

Header constant Header value Type Description

Jt400Endpoint.SENDER_INFORMATION

"SENDER_INFORMATION"

String

Returns the sender information for this data queue entry, or an empty string if not available

Consumer headers when consuming from message queues

The following headers are potentially available. If the values could not be determined, the headers will not be set

Header constant Header value Type Description

Jt400Constants.MESSAGE

"CamelJt400Message"

QueuedMessage

The message received

Jt400Constants.MESSAGE_ID

"CamelJt400MessageID"

String

The message identifier

Jt400Constants.MESSAGE_FILE

"CamelJt400MessageFile"

String

The message file name

Jt400Constants.MESSAGE_TYPE

"CamelJt400MessageType"

Integer

The message type (corresponds to constants defined in the AS400Message class)

Jt400Constants.MESSAGE_SEVERITY

"CamelJt400MessageSeverity"

Integer

The message severity (Valid values are between 0 and 99, or -1 if it is not set)

Jt400Constants.MESSAGE_DFT_RPY

"CamelJt400MessageDefaultReply"

String

The default message reply, when the message is an inquiry message

Jt400Constants.MESSAGE_REPLYTO_KEY

"CamelJt400MessageReplyToKey"

byte[]

The key of the message that will be replied to (if the sendingReply parameter is set to true)

Jt400Constants.SENDER_INFORMATION

"SENDER_INFORMATION"

String

The job identifier of the sending job

Producer headers when sending to message queues

Jt400Constants.MESSAGE_REPLYTO_KEY "CamelJt400MessageReplyToKey" byte[] If set, and if the message body is not empty, a new message will not be sent to the provided message queue. Instead, a response will be sent to the message identified by the given key. This is set automatically when reading from the message queue if the sendingReply parameter is set to true.

Example

In the snippet below, the data for an exchange sent to the direct:george endpoint will be put in the data queue PENNYLANE in library BEATLES on a system named LIVERPOOL.
Another user connects to the same data queue to receive the information from the data queue and forward it to the mock:ringo endpoint.

public class Jt400RouteBuilder extends RouteBuilder {
    @Override
    public void configure() throws Exception {
       from("direct:george").to("jt400://GEORGE:EGROEG@LIVERPOOL/QSYS.LIB/BEATLES.LIB/PENNYLANE.DTAQ");
       from("jt400://RINGO:OGNIR@LIVERPOOL/QSYS.LIB/BEATLES.LIB/PENNYLANE.DTAQ").to("mock:ringo");
    }
}

Program call examples

In the snippet below, the data Exchange sent to the direct:work endpoint will contain three string that will be used as the arguments for the program “compute” in the library “assets”. This program will write the output values in the 2nd and 3rd parameters. All the parameters will be sent to the direct:play endpoint.

public class Jt400RouteBuilder extends RouteBuilder {
    @Override
    public void configure() throws Exception {
       from("direct:work").to("jt400://GRUPO:ATWORK@server/QSYS.LIB/assets.LIB/compute.PGM?fieldsLength=10,10,512&ouputFieldsIdx=2,3").to(“direct:play”);
    }
}

In this example, the camel route will call the QUSRTVUS API to retrieve 16 bytes from data area "MYUSRSPACE" in the "MYLIB" library.

public class Jt400RouteBuilder extends RouteBuilder {
    @Override
    public void configure() throws Exception {
        from("timer://foo?period=60000")
        .process( exchange -> {
            String usrSpc = "MYUSRSPACEMYLIB     ";
            Object[] parms = new Object[] {
                usrSpc, // Qualified user space name
                1,      // starting position
                16,     // length of data
                "" // output
            };
            exchange.getIn().setBody(parms);
        })
        .to("jt400://*CURRENT:*CURRENt@localhost/qsys.lib/QUSRTVUS.PGM?fieldsLength=20,4,4,16&outputFieldsIdx=3")
        .setBody(simple("${body[3]}"))
        .to("direct:foo");
    }
}

Writing to keyed data queues

from("jms:queue:input")
.to("jt400://username:password@system/lib.lib/MSGINDQ.DTAQ?keyed=true");

Reading from keyed data queues

from("jt400://username:password@system/lib.lib/MSGOUTDQ.DTAQ?keyed=true&searchKey=MYKEY&searchType=GE")
.to("jms:queue:output");

Writing to message queues

from("jms:queue:input")
.to("jt400://username:password@system/lib.lib/MSGINQ.MSGQ");

Reading from a message queue

from("jt400://username:password@system/lib.lib/MSGOUTQ.MSGQ")
.to("jms:queue:output");

Replying to an inquiry message on a message queue

from("jt400://username:password@localhost/qsys.lib/qusrsys.lib/myq.msgq?sendingReply=true")
.choice()
    .when(header(Jt400Constants.MESSAGE_TYPE).isEqualTo(AS400Message.INQUIRY))
        .process((exchange) -> {
            String reply = // insert reply logic here
            exchange.getIn().setBody(reply);
        })
        .to("jt400://username:password@localhost/qsys.lib/qusrsys.lib/myq.msgq");

Spring Boot Auto-Configuration

When using jt400 with Spring Boot make sure to use the following Maven dependency to have support for auto configuration:

<dependency>
  <groupId>org.apache.camel.springboot</groupId>
  <artifactId>camel-jt400-starter</artifactId>
  <version>x.x.x</version>
  <!-- use the same version as your Camel core version -->
</dependency>

The component supports 5 options, which are listed below.

Name Description Default Type

camel.component.jt400.autowired-enabled

Whether autowiring is enabled. This is used for automatic autowiring options (the option must be marked as autowired) by looking up in the registry to find if there is a single instance of matching type, which then gets configured on the component. This can be used for automatic configuring JDBC data sources, JMS connection factories, AWS Clients, etc.

true

Boolean

camel.component.jt400.bridge-error-handler

Allows for bridging the consumer to the Camel routing Error Handler, which mean any exceptions occurred while the consumer is trying to pickup incoming messages, or the likes, will now be processed as a message and handled by the routing Error Handler. By default the consumer will use the org.apache.camel.spi.ExceptionHandler to deal with exceptions, that will be logged at WARN or ERROR level and ignored.

false

Boolean

camel.component.jt400.connection-pool

Default connection pool used by the component. Note that this pool is lazily initialized. This is because in a scenario where the user always provides a pool, it would be wasteful for Camel to initialize and keep an idle pool. The option is a com.ibm.as400.access.AS400ConnectionPool type.

AS400ConnectionPool

camel.component.jt400.enabled

Whether to enable auto configuration of the jt400 component. This is enabled by default.

Boolean

camel.component.jt400.lazy-start-producer

Whether the producer should be started lazy (on the first message). By starting lazy you can use this to allow CamelContext and routes to startup in situations where a producer may otherwise fail during starting and cause the route to fail being started. By deferring this startup to be lazy then the startup failure can be handled during routing messages via Camel’s routing error handlers. Beware that when the first message is processed then creating and starting the producer may take a little time and prolong the total processing time of the processing.

false

Boolean