The jdbc component enables you to access databases through JDBC, where SQL queries and operations are sent in the message body. This component uses the standard JDBC API, unlike the SQL Component component, which uses spring-jdbc.
jdbc:dataSourceName[?options]
This component supports producer endpoints only.
You can append query options to the URI in the following format,
?option=value&option=value&...
Maven users need to add the following dependency to their
pom.xml
for this component:
<dependency> <groupId>org.apache.camel</groupId> <artifactId>camel-jdbc</artifactId> <version>x.x.x</version> <!-- use the same version as your Camel core version --> </dependency>
![]() | Warning |
---|---|
This component can only be used to define producer endpoints,
which means that you cannot use the JDBC component in a
|
![]() | Important |
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This component cannot be used as a transactional client. If you need transaction support in your route, use the SQL Component component instead. |
Name | Description |
---|---|
readSize
|
The default maximum number of rows that can be read by a polling query. The defaut is |
statement.<xxx>
|
Apache Camel 2.1: Sets
additional options on the
For details, see the The default is |
useJDBC4ColumnNameAndLabel
Semantics
|
Specifies whether to use JDBC 4/3 column label/name semantics. Set this
option to The default is |
resetAutoCommit
|
Camel 2.9: Camel sets
the If the JDBC connection doesn't
support resetting
the The default is |
allowNamedParameters
|
Camel 2.12: Whether to allow using named parameters in the queries. The default is |
Camel 2.12: Allows to
plugin to use a custom
The default is |
|
useHeadersAsParameters
|
Camel 2.12: Set this option
to The default is |
outputType
|
Camel 2.12.1: Make
the output of the producer to
The default is |
outputClass
|
Camel 2.12.1: Specify the
full package and class name to use as conversion when
The default is |
beanRowMapper
|
Camel 2.12.1: To use a
custom
|
By default, the result is returned in the OUT body as an
ArrayList<HashMap<String, Object>>
. The
List
object contains the list of rows and the
Map
objects contain each row with the
String
key as the column name.
![]() | Note |
---|---|
This component fetches |
Header | Description |
---|---|
CamelJdbcRowCount
|
If the query is a SELECT , the row count
is returned in this OUT header. |
CamelJdbcUpdateCount
|
If the query is an UPDATE , the update
count is returned in this OUT header. |
CamelGeneratedKeysRows
|
Camel 2.10: Rows that contains the generated kets. |
CamelGeneratedKeysRowCount
|
Camel 2.10: The number of rows in the header that contains generated keys. |
CamelJdbcColumnNames
|
Camel 2.11.1: The column
names from the ResultSet as a
java.util.Set type. |
CamelJdbcParametes
|
Camel 2.12: A
java.util.Map which has the headers
to be used if useHeadersAsParameters has
been enabled. |
Available as of 2.10.
The RDBMS may support autogenerated keys if you insert data using
SQL INSERT. If so, you can instruct the JDBC producer to return the
generated keys in headers. To do so, set the header
CamelRetrieveGenerateKeys=true
, and then the
generated keys will be returned as headers with the keys listed in
Message Headers.
You can see more details in this unit test.
![]() | Important |
---|---|
Using generated keys does not work with together with named parameters. |
Available as of Camel 2.12
In the given route below, we want to get all the projects from the projects table. Notice the SQL query has 2 named parameters, :?lic and :?min. Camel will then lookup these parameters from the message headers. Notice in the example above we set two headers with constant value for the named parameters:
from("direct:projects") .setHeader("lic", constant("ASF")) .setHeader("min", constant(123)) .setBody("select * from projects where license = :?lic and id > :?min order by id") .to("jdbc:myDataSource?useHeadersAsParameters=true")
You can also store the header values in a
java.util.Map
and store the map on the
headers with the key CamelJdbcParameters
.
In the following example, we fetch the rows from the customer table.
First we register our datasource in the Apache Camel registry as
testdb
:
JndiRegistry reg = super.createRegistry(); reg.bind("testdb", ds); return reg;
Then we configure a route that routes to the JDBC component, so
the SQL will be executed. Note how we refer to the
testdb
datasource that was bound in the
previous step:
// lets add simple route public void configure() throws Exception { from("direct:hello").to("jdbc:testdb?readSize=100"); }
Or you can create a DataSource
in Spring like
this:
<camelContext id="camel" xmlns="http://camel.apache.org/schema/spring"> <route> <from uri="timer://kickoff?period=10000"/> <setBody> <constant>select * from customer</constant> </setBody> <to uri="jdbc:testdb"/> <to uri="mock:result"/> </route> </camelContext> <!-- Just add a demo to show how to bind a date source for camel in Spring--> <bean id="testdb" class="org.springframework.jdbc.datasource.DriverManagerDataSource"> <property name="driverClassName" value="org.hsqldb.jdbcDriver"/> <property name="url" value="jdbc:hsqldb:mem:camel_jdbc" /> <property name="username" value="sa" /> <property name="password" value="" /> </bean>
We create an endpoint, add the SQL query to the body of the IN message, and then send the exchange. The result of the query is returned in the OUT body:
// first we create our exchange using the endpoint Endpoint endpoint = context.getEndpoint("direct:hello"); Exchange exchange = endpoint.createExchange(); // then we set the SQL on the in body exchange.getIn().setBody("select * from customer order by ID"); // now we send the exchange to the endpoint, and receives the response from Camel Exchange out = template.send(endpoint, exchange); // assertions of the response assertNotNull(out); assertNotNull(out.getOut()); ArrayList<HashMap<String, Object>> data = out.getOut().getBody(ArrayList.class); assertNotNull("out body could not be converted to an ArrayList - was: " + out.getOut().getBody(), data); assertEquals(2, data.size()); HashMap<String, Object> row = data.get(0); assertEquals("cust1", row.get("ID")); assertEquals("jstrachan", row.get("NAME")); row = data.get(1); assertEquals("cust2", row.get("ID")); assertEquals("nsandhu", row.get("NAME"));
If you want to work on the rows one by one instead of the entire ResultSet at once you need to use the Splitter EIP such as:
from("direct:hello") // here we split the data from the testdb into new messages one by one // so the mock endpoint will receive a message per row in the table .to("jdbc:testdb").split(body()).to("mock:result");
If we want to poll a database using the JDBC component, we need to combine it with a polling scheduler such as the Timer or Quartz etc. In the following example, we retrieve data from the database every 60 seconds:
from("timer://foo?period=60000").setBody(constant("select * from customer")).to("jdbc:testdb").to("activemq:queue:customers");
See also: