Question

I have what I think is a simple problem but have been unable to solve…
For some reason I have a controller that uses removeFrom*.save() which throws no errors but does not do anything.

Running
Grails 1.2
Linux/Ubuntu

The following application is stripped down to reproduce the problem…

I have two domain objects via create-domain-class
– Job (which has many notes)
– Note (which belongs to Job)

I have 3 controllers via create-controller
– JobController (running scaffold)
– NoteController (running scaffold)
– JSONNoteController

JSONNoteController has one primary method deleteItem which aims to remove/delete a note.

It does the following

• some request validation
• removes the note from the job – jobInstance.removeFromNotes(noteInstance).save()
• deletes the note – noteInstance.delete()
• return a status and remaining data set as a json response.

When I run this request – I get no errors but it appears that jobInstance.removeFromNotes(noteInstance).save() does nothing and does not throw any exception etc.
How can I track down why??

I’ve attached a sample application that adds some data via BootStrap.groovy.
Just run it – you can view the data via the default scaffold views.

If you run linux, from a command line you can run the following
GET “http://localhost:8080/gespm/JSONNote/deleteItem?job.id=1&note.id=2”

You can run it over and over again and nothing different happens. You could also paste the URL into your webbrowser if you’re running windows.

Please help – I’m stuck!!!
Code is here link text

Note Domain

package beachit

class Note
{

    Date dateCreated
    Date lastUpdated

    String note

    static belongsTo = Job

    static constraints =
    {
    }

    String toString()
    {
        return note
    }
}

Job Domain

package beachit

class Job
{

    Date dateCreated
    Date lastUpdated

    Date        createDate
    Date        startDate
    Date        completionDate

    List notes

    static hasMany = [notes : Note]

    static constraints =
    {
    }

    String toString()
    {
        return createDate.toString() + " " + startDate.toString();
    }
}

JSONNoteController

package beachit

import grails.converters.*
import java.text.*

class JSONNoteController
{

    def test = { render "foobar test"  }

    def index = { redirect(action:listAll,params:params) }

    // the delete, save and update actions only accept POST requests
    //static allowedMethods = [delete:'POST', save:'POST', update:'POST']

    def getListService =
    {
        def message
        def status
        def all = Note.list()

        return all
    }

    def getListByJobService(jobId)
    {
        def message
        def status

        def jobInstance = Job.get(jobId)
        def all

        if(jobInstance)
        {
            all = jobInstance.notes
        }
        else
        {
            log.debug("getListByJobService job not found for jobId " + jobId)
        }

        return all

    }

    def listAll =
    {
        def message
        def status
        def listView

        listView    = getListService()
        message     = "Done"
        status      = 0

        def response = ['message': message, 'status':status, 'list': listView]
        render response as JSON
    }

    def deleteItem =
    {
        def jobInstance
        def noteInstance
        def message
        def status
        def jobId = 0
        def noteId = 0
        def instance
        def listView
        def response

        try
        {
            jobId = Integer.parseInt(params.job?.id)
        }
        catch (NumberFormatException ex)
        {
            log.debug("deleteItem error in jobId " + params.job?.id)
            log.debug(ex.getMessage())
        }

        if (jobId && jobId > 0 )
        {
            jobInstance = Job.get(jobId)

            if(jobInstance)
            {
                if (jobInstance.notes)
                {
                    try
                    {
                        noteId = Integer.parseInt(params.note?.id)
                    }
                    catch (NumberFormatException ex)
                    {
                        log.debug("deleteItem error in noteId " + params.note?.id)
                        log.debug(ex.getMessage())
                    }

                    log.debug("note id =" + params.note.id)
                    if (noteId && noteId > 0 )
                    {
                        noteInstance = Note.get(noteId)
                        if (noteInstance)
                        {
                            try
                            {
                                jobInstance.removeFromNotes(noteInstance).save()
                                noteInstance.delete()

                                message = "note ${noteId} deleted"
                                status = 0
                            }
                            catch(org.springframework.dao.DataIntegrityViolationException e)
                            {
                                message = "Note ${noteId} could not be deleted - references to it exist"
                                status = 1
                            }
                            /*
                            catch(Exception e)
                            {
                                message = "Some New Error!!!"
                                status = 10
                            }
                            */
                        }
                        else
                        {
                            message = "Note not found with id ${noteId}"
                            status  = 2
                        }
                    }
                    else
                    {
                        message = "Couldn't recognise Note id : ${params.note?.id}"
                        status = 3
                    }
                }
                else
                {
                    message = "No Notes found for Job : ${jobId}"
                    status = 4
                }
            }
            else
            {
                message = "Job not found with id ${jobId}"
                status = 5
            }

            listView    = getListByJobService(jobId)

        } // if (jobId)
        else
        {
            message = "Couldn't recognise Job id : ${params.job?.id}"
            status = 6
        }

        response = ['message': message, 'status':status, 'list' : listView]
        render response as JSON

    } // deleteNote
}

Answer 1

See this thread: http://grails.1312388.n4.nabble.com/GORM-doesn-t-inject-hashCode-and-equals-td1370512.html

I would recommend using a base class for your domain objects like this:

abstract class BaseDomain {

    @Override
    boolean equals(o) {
        if(this.is(o)) return true
        if(o == null) return false
        // hibernate creates dynamic subclasses, so 
        // checking o.class == class would fail most of the time
        if(!o.getClass().isAssignableFrom(getClass()) && 
            !getClass().isAssignableFrom(o.getClass())) return false

        if(ident() != null) {
            ident() == o.ident()
        } else {
            false
        }
    }

    @Override
    int hashCode() {
        ident()?.hashCode() ?: 0
    }

}

That way, any two objects with the same non-null database id will be considered equal.