groovy.lang

Annotation Type GrabConfig

@Retention(value=SOURCE)
@Target(value={CONSTRUCTOR,FIELD,LOCAL_VARIABLE,METHOD,PARAMETER,TYPE})
public @interface GrabConfig

Used to modify the grape configuration for grab requests.

An example involving databases:

 @Grab('mysql:mysql-connector-java:5.1.6'),
 @GrabConfig(systemClassLoader=true)
 import groovy.sql.Sql

 def sql=Sql.newInstance("jdbc:mysql://localhost/test", "user", "password", "com.mysql.jdbc.Driver")
 println sql.firstRow('SELECT * FROM INFORMATION_SCHEMA.COLUMNS')
 

Another example involving XStream:

 @Grapes([
     @Grab('com.thoughtworks.xstream:xstream:1.3.1'),
     @Grab('xpp3:xpp3_min:1.1.4c'),
     @GrabConfig(systemClassLoader=true, initContextClassLoader=true)
 ])
 import com.thoughtworks.xstream.*

 class Staff {
     String firstname, lastname, position
 }

 def xstream = new XStream()
 def john1 = new Staff(firstname:'John',
                      lastname:'Connor',
                      position:'Resistance Leader')

 // write out to XML file
 new File("john.xml").withOutputStream { out ->
     xstream.toXML(john1, out)
 }

 // now read back in
 def john2
 new File("john.xml").withInputStream { ins ->
     john2 = xstream.fromXML(ins)
 }

 println john2.dump()
 

Further information about customising grape behavior can be found on the Grape documentation page: http://groovy.codehaus.org/Grape.

Optional Element Summary

Optional Elements

Modifier and Type	Optional Element and Description
boolean	initContextClassLoader Set to true if you want the context classloader to be initialised to the classloader of the current class or script.
boolean	systemClassLoader Set to true if you want to use the system classloader when loading the grape.

Element Detail

systemClassLoader

public abstract boolean systemClassLoader

Set to true if you want to use the system classloader when loading the grape. This is normally only required when a core Java class needs to reference the grabbed classes, e.g. for a database driver accessed using DriverManager.

Default:

false

initContextClassLoader

public abstract boolean initContextClassLoader

Set to true if you want the context classloader to be initialised to the classloader of the current class or script. This is useful for libraries or frameworks that assume that the context classloader has been set. But be careful when using this flag as your script or class might behave differently when called directly (from the command line or from an IDE) versus when called from within a container, e.g. a web container or a JEE container.

Default:

false