The ibatis: component allows you to query, poll, insert, update and delete data in a relational database using Apache iBATIS.
Maven users will need to add the following dependency to their
pom.xml
for this component:
<dependency> <groupId>org.apache.camel</groupId> <artifactId>camel-ibatis</artifactId> <version>x.x.x</version> <!-- use the same version as your Camel core version --> </dependency>
ibatis:statementName[?options]
Where statementName is the name in the iBATIS XML configuration file which maps to the query, insert, update or delete operation you wish to evaluate.
You can append query options to the URI in the following format,
?option=value&option=value&...
This component will by default load the iBatis SqlMapConfig file
from the root of the classpath and expected named as
SqlMapConfig.xml
. It uses Spring resource
loading so you can define it using classpath
,
file
or http
as prefix to
load resources with those schemes. In Camel 2.2 you can configure
this on the iBatisComponent with the
setSqlMapConfig(String)
method.
Table 53 lists the iBATIS uri options:
Table 53. URI options
Option | Type | Default | Description |
---|---|---|---|
consumer.onConsume
|
String
|
null
| Statements to run after consuming. Can be used, for example, to update rows after they have been consumed and processed in Apache Camel. See sample later. Multiple statements can be separated with comma. |
consumer.useIterator
|
boolean
|
true
| If true each row returned
when polling will be processed individually. If
false the entire
List of data is set as the IN
body. |
consumer.routeEmptyResultSet
|
boolean
|
false
| Apache Camel 2.0: Sets whether empty result set should be routed or not. By default, empty result sets are not routed. |
statementType
|
StatementType
|
null
| Apache Camel
1.6.1/2.0: Mandatory to specify for
IbatisProducer to control which iBatis
SqlMapClient method to
invoke. The enum values are:
QueryForObject ,
QueryForList ,
Insert ,
Update ,
Delete . |
maxMessagesPerPoll
|
int
|
0
| Apache Camel 2.0: An integer to define a maximum messages to gather per poll. By default, no maximum is set. Can be used to set a limit of e.g. 1000 to avoid when starting up the server that there are thousands of files. Set a value of 0 or negative to disabled it. |
Apache Camel will populate the result message, either IN or OUT, with a header using the specified statement name:
Table 54. Message header options
Header | Type | Description |
---|---|---|
CamelIBatisStatementName
|
String
| Apache Camel 2.0: The statementName used (for example: insertAccount). |
CamelIBatisResult
|
Object
| Apache Camel 1.6.2/2.0: The response returned from
iBatis in any of the operations. For example, an
INSERT could return the
auto-generated key, or number of rows etc. |
Apache Camel 1.6.1: The response from iBatis will be set as OUT body.
Apache Camel
1.6.2/2.0: The response from iBatis will only be set
as body if it's a SELECT
statement. That means,
for example, for INSERT
statements Apache Camel will
not replace the body. This allows you to continue routing and keep
the original body. The response from iBatis is always stored in the
header with the key CamelIBatisResult
.
For example if you wish to consume beans from a JMS queue and insert them into a database you could do the following:
from("activemq:queue:newAccount"). to("ibatis:insertAccount?statementType=Insert");
Notice we have to specify the statementType
, as
we need to instruct Apache Camel which
SqlMapClient
operation to invoke.
Where insertAccount is the iBatis ID in the SQL map file:
<!-- Insert example, using the Account parameter class --> <insert id="insertAccount" parameterClass="Account"> insert into ACCOUNT ( ACC_ID, ACC_FIRST_NAME, ACC_LAST_NAME, ACC_EMAIL ) values ( #id#, #firstName#, #lastName#, #emailAddress# ) </insert>
Available as of Apache Camel
1.6.1/2.0 When routing to an iBatis endpoint you want
more fine grained control so you can control whether the SQL
statement to be executed is a SELEECT
,
UPDATE
, DELETE
or
INSERT
etc. This is now possible in Apache
Camel 1.6.1/2.0. So, for example, if we want to route to an iBatis
endpoint in which the IN body contains parameters to a
SELECT
statement we can do:
from("direct:start") .to("ibatis:selectAccountById?statementType=QueryForObject") .to("mock:result");
In the code above, we can invoke the iBatis statement
selectAccountById
, and the IN body should
contain the account id we want to retrieve, such as an
Integer
type.
We can do the same for some of the other operations, such as
QueryForList
:
from("direct:start") .to("ibatis:selectAllAccounts?statementType=QueryForList") .to("mock:result");
And the same for UPDATE
, where we can send an
Account
object as IN body to iBatis:
from("direct:start") .to("ibatis:updateAccount?statementType=Update") .to("mock:result");
Since this component does not support scheduled polling, you need to use another mechanism for triggering the scheduled polls, such as the Timer or Quartz components.
In the sample below we poll the database, every 30 seconds using the Timer component and send the data to the JMS queue:
from("timer://pollTheDatabase?delay=30000").to("ibatis:selectAllAccounts?statementType=QueryForList").to("activemq:queue:allAccounts");
And the iBatis SQL map file used:
<!-- Select with no parameters using the result map for Account class. --> <select id="selectAllAccounts" resultMap="AccountResult"> select * from ACCOUNT </select>
This component supports executing statements after data have been consumed and processed by
Apache Camel. This allows you to do post updates in the database.
Notice all statements must be UPDATE
statements.
Apache Camel supports executing multiple statements whose name
should be separated by comma.
The route below illustrates we execute the consumeAccount statement data is processed. This allows us to change the status of the row in the database to processed, so we avoid consuming it twice or more.
from("ibatis:selectUnprocessedAccounts?consumer.onConsume=consumeAccount").to("mock:results");
And the statements in the sqlmap file:
<select id="selectUnprocessedAccounts" resultMap="AccountResult"> select * from ACCOUNT where PROCESSED = false </select>
<update id="consumeAccount" parameterClass="Account"> update ACCOUNT set PROCESSED = true where ACC_ID = #id# </update>