invoke

Invoke a java method or script snippet.

For a script, the source must be a javax.script.Invocable object.

For a java method, the source specifies the object on which to invoke the method. If the source is a class then the static method of the class is invoked.

Property Summary

function	The function/method to call.
parameters	The values to use as arguments.
source	The java object or script Invocable on which to invoke the method/function.
static	Indicates that the source contains a a java class and a static method on the class is to be invoked.

Example Summary

Example 1	Invoke a method on a bean.
Example 2	Invoke a static method of a class.
Example 3	Invoking a function of a script.

Property Detail

function

Configured By	ATTRIBUTE
Access	READ_WRITE
Required	Yes.

The function/method to call.

parameters

Configured By	ELEMENT
Access	READ_WRITE
Required	Must match the expected arguments..

The values to use as arguments.

source

Configured By	ELEMENT
Access	READ_WRITE
Required	Yes.

The java object or script Invocable on which to invoke the method/function.

static

Configured By	ATTRIBUTE
Access	READ_WRITE
Required	No.

Indicates that the source contains a a java class and a static method on the class is to be invoked.

Examples

Example 1

Invoke a method on a bean. The method takes a single date parameter which is uses to generate a time of day dependent greeting.

<oddjob>
    <job>
        <sequential>
            <jobs>
                <variables id="vars">
                    <message>
                        <invoke function="greeting">
                            <source>
                                <bean class="org.oddjob.script.GreetingService"/>
                            </source>
                            <parameters>
                                <schedule>
                                    <date>
                                        <value value="${date}"/>
                                    </date>
                                    <schedule>
                                        <schedules:now xmlns:schedules="http://rgordon.co.uk/oddjob/schedules"/>
                                    </schedule>
                                </schedule>
                            </parameters>
                        </invoke>
                    </message>
                </variables>
                <echo id="echo-greeting">${vars.message}</echo>
            </jobs>
        </sequential>
    </job>
</oddjob>

The ${date} reference is there so that it can be injected during a test, to get a guaranteed result. When this is example is run as is, this is null so the system clock to be used there by giving a real time based greeting.

One subtle point to note about Oddjob configuration that this example highlights is to do with when types are resolved. The invoke type will be resolved when the echo job is run. The schedule type will be resolved when the variables job is run. If the echo job were scheduled to run several hours after the variables job had run it would not give the correct greeting!

Example 2

Invoke a static method of a class.

<oddjob>
    <job>
        <sequential>
            <jobs>
                <variables id="vars">
                    <message>
                        <invoke function="greetPerson" static="true">
                            <source>
                                <class name="org.oddjob.script.GreetingService"/>
                            </source>
                            <parameters>
                                <value value="John"/>
                            </parameters>
                        </invoke>
                    </message>
                </variables>
                <echo id="echo-greeting">${vars.message}</echo>
            </jobs>
        </sequential>
    </job>
</oddjob>

Example 3

Invoking a function of a script. See the script examples.