Japanese Controller Dynamic Methods

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????????????????????????? Controller Dynamic Methods & Properties

?????? Properties

actionUri

?? Description

The relative Uri of the action ????????URI

controllerUri

?? Description

The relative Uri of the controller ??????????URI

actionName

?? Description

The name of the current action ?????????

controllerName

?? Description

The name of the current controller ???????????

flash

?? Description

A map that allows temporary storage of objects for the next request and the next request only. The subequent request will clear the storage of any variables stored in the first request. This is a convenience map that allows you to store information temporarily, which is very convenient when using redirection or chaining. ?????????????????????????????????????????? ???????????????????????????????????????????????? ?????? (redirection)???????(chaining) ????????????????????????????????

? Example

flash['message'] = 'hello world!'

grailsApplication

?? Description

An instance of org.codehaus.groovy.grails.commons.GrailsApplication that provides information about the grails application Grails????????????????org.codehaus.groovy.grails.commons.GrailsApplication???????

? Example

return [controllers : grailsApplication.controllers]

grailsAttributes

?? Description

An instance of org.codehaus.groovy.grails.web.servlet.GrailsApplicationAttributes that provides convenience methods for the current grails request

? Example

def templateUri = grailsAttributes.getTemplateUri("myTemplate",request)

log

?? Description

An instance of the Log4J logger for the controller. Grails creates a log per controller, which you can call on at any time to perform logging. When configuring Log4J using WEB-INF/log4j.properties you should use properties of the form:

log4j.logger.TestController=debug, stdout

Where "TestController" is the fully qualified class name of your controller class.

? Example

You simply use the standard Log4J logging methods: 

log.trace('Doing something')
log.debug('Debug info here')
log.error('Something went wrong')
log.error('Something went wrong', someException)

params

?? Description

A map of the available request parameters and/or controller parameters ???????????????????????????????????.

? Example

def a = Account.get( params["id"] )

request

?? Description

The HttpServletRequest instance for the request. Request attributes can be accessed with the Map syntax provided by groovy HttpServletRequest???????Groovy?Map?????????????????????

? Example

request['anAttribute']
request.getHeader("user-agent")

response

?? Description

The HttpServletResponse instance HttpServletResponse??????

? Example

response.setHeader("myheader", "myvalue")

servletContext

?? Description

The ServletContext instance as per the servlet API Servlet API??????ServletContext??????

? Example

def myUrl = servletContext.getResource("/path/to/url")

session

?? Description

Provides access to a map of the HttpSession instance HttpSession???????????????

? Example

def loggedUser = session["loggedUser"]

???? Methods

bindData

?? Description

Binds data to a target instance performing type conversion if necessary. Useful for binding request parameters to properties of objects ?????????????????????????????????.?????????????????????????????????????

????? Parameters
  • target - ???????? The target object to bind to
  • params - ????????? The parameters to bind to the target object
? Examples

bindData(target, this.params) // ????????????????????????? binds request parameters to a target object

chain

?? Description

Chains the model (The model is retained from one action to the next) from one action to the next allowing you to build up the model from an action chain.

????? Parameters
  • uri - The full uri to redirect to (example /book/list, book/show/2)
  • controller - The controller to redirect to, defaults to the current controller if not specified
  • action - The action to redirect to, either a string name or a reference to an action within the current controller
  • id - The id to use in redirection
  • params - Parameters to pass to the action redirected to.
  • model (required) - The model to chain to the next action
  • params (optional) - Parameters to pass to the action chained to.
? Examples

chain(action:"details",model:[book:new Book(title:'The Shawshank Redemption')])

getViewUri

?? Description

Retrieves the relative uri of a named view within the Grails application. If the view contains a '/' at the start it will be resolved relative to the views folder as a shared view otherwise it will be relative to the current controller

????? Parameters
  • name (required) - The name of the view
? Examples

assert getViewUri('myView') == /WEB-INF/grails-app/views/controllerName/myView.gsp
assert getViewUri('/mySharedView') == /WEB-INF/grails-app/views/mySharedView.gsp

getTemplateUri

?? Description

Retrieves the relative uri of a named template within the Grails application. If the template contains a '/' at the start it will be resolved relative to the views folder as a shared template otherwise it will be relative to the current controller

????? Parameters
  • name (required) - The name of the template
? Examples

assert getTemplateUri('myTemplate') == /WEB-INF/grails-app/views/controllerName/_myTemplate.gsp
assert getTemplateUri('/mySharedTemplate') == /WEB-INF/grails-app/views/_mySharedTemplate.gsp

redirect

?? Description

Redirects the current action to another action, optionally passing parameters and/or errors ?????????????????????????????????????/???????????

????? Parameters
  • uri - ??????????uri The full uri to redirect to (example /book/list, book/show/2)
  • controller - ???????????????????????????????? The controller to redirect to, defaults to the current controller if not specified
  • action - ????????????? The action to redirect to, either a string name or a reference to an action within the current controller
  • id - ???????????id The id to use in redirection
  • params - ????????????????????? Parameters to pass to the action redirected to.
? Examples

redirect(uri:"book/list")
redirect(action:"show")
redirect(controller:"book",action:"list")
redirect(action:"show",id:4, params:[author:"Stephen King"])

render

?? Description

A multi-purpose method for rendering responses to the client which is best illustrated with a few examples! ????????????????

????? Parameters
  • text (optional) - ??????? The text to render
  • builder (optional) - ???????????????????? The builder to use when rendering markup
  • view (optional) - The view to delegate the rendering to
  • template (optional) - ????????????? The template to render
  • var (optional) - ??????????????????? Groovy?????????'it'??????? The name of the variable to be passed into a template, defaults to the groovy default argument 'it' if not specified
  • bean (optional) - ?????????? The beanto use in rendering
  • model (optional) - ?????????? The model to use in rendering
  • collection (optional) - ???????????????????????????????????? For rendering a template against each item in a collection
  • contentType (optional) - ?????????????? The contentType of the response
  • encoding (optional) - ?????????????? The encoding of the response
? Examples

// renders text to response
// ??????
render "some text"
// renders text for a specified content-type/encoding
// ?????????????/???????????????
render(text:"<xml>some xml</xml>",contentType:"text/xml",encoding:"UTF-8")
// render a template to the response for the specified model
// ??????????????????????
render(template:"book",model:[book:new Book(title:'The Shining',author:'Stephen King')])
// render each item in the collection using the specified template
// ???????????????????????????
render(template:"book",collection:[b1, b2, b3])
// render a template to the response for the specified bean
// ??????????????????????
render(template:"book",bean:new Book(title:'The Shining',author:'Stephen King'))
// render the view with the specified model
// ???????????????
render(view:"viewName",model:[book:new Book(author:'Stephen King')])
// render the view with the controller as the model
// ?????????????????????
render(view:"viewName"
)
// render some markup to the response
//????????????????
render {
    div(id:"myDiv") {
           "some body text"
    }
}
// render some XML markup to the response
// XML????????????????
render(contentType:"text/xml") {
    books {
         for(b in books) {
            book(title:b.title,author:b.author)
         }
    }
}
// render an OpenRico (http://www.openrico.org) response with the builder attribute:
// ???????OpenRico (http://www.openrico.org)????????:
def b = new Book(title:"Kiss the Girls", author:"James Patterson")
render(builder:"rico") {
     object(id:"bookUpdater") {
            book(author:b.title,author:b.author)
     }
}
// render a JSON ( http://www.json.org ) response with the builder attribute:
// ???????JSON ( http://www.json.org )????????:
render(builder:"json") {
	book(author:b.title,author:b.author)
}