Lift Framework example source code file (CRUDify.scala)

This example Lift Framework source code file (CRUDify.scala) is included in the DevDaily.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" ^TM.

Java - Lift Framework tags/keywords

boolean, box, crudify, crudtype, crudtype, fieldpointertype, fieldpointertype, list, list, mappedfield, mybridge, string, thecrudtype, thecrudtype

The Lift Framework CRUDify.scala source code

/*
 * Copyright 2006-2011 WorldWide Conferencing, LLC
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package net.liftweb
package mapper

import sitemap._
import Loc._
import http._
import util._
import common._
import Helpers._

import scala.xml._

/**
 * This trait automatically adds CRUD (Create, read, update and delete) operations
 * to an existing <b>MetaMapper object. Various methods can be overridden to
 * customize which operations are available to a user and how things are displayed.
 * For example, you can disable deletion of entities by overriding deleteMenuLoc to Empty.
 *
 * Note: Compilation will fail if you try to mix this into a Mapper instead of the
 * associated MetaMapper. You have been warned.
 */
trait CRUDify[KeyType, CrudType <: KeyedMapper[KeyType, CrudType]] extends 
  net.liftweb.proto.Crudify {
  self: CrudType with KeyedMetaMapper[KeyType, CrudType] =>

  /**
   * What's the record type for the underlying CRUDify?
   */
  type TheCrudType = CrudType

  /**
   * What's a field pointer for the underlying CRUDify
   */
  type FieldPointerType = MappedField[_, CrudType]

  /**
   * Given a field pointer and an instance, get the field on that instance
   */
  protected def computeFieldFromPointer(instance: TheCrudType, pointer: FieldPointerType): Box[BaseField] = Full(getActualField(instance, pointer))

  /**
   * Given a String that represents the primary key, find an instance of
   * TheCrudType
   */
  def findForParam(in: String): Box[TheCrudType] = find(in)

  /**
   * Get a List of items from the databased
   */
  def findForList(start: Long, count: Int): List[TheCrudType] =
  findAll(StartAt[CrudType](start) :: MaxRows[CrudType](count) ::
          findForListParams :_*)

  /**
   * What are the query parameters?  Default to ascending on primary key
   */
  def findForListParams: List[QueryParam[CrudType]] =
  List(OrderBy(primaryKeyField, Ascending))

  /**
  * The fields to be displayed. By default all the displayed fields,
  * but this list
  * can be shortened.
  */
  def fieldsForDisplay: List[MappedField[_, CrudType]] = 
    mappedFieldsForModel.filter(_.dbDisplay_?)

  /**
   * What's the prefix for this CRUD.  Typically the table name
   */
  def calcPrefix = List(_dbTableNameLC)


  protected class MyBridge(in: CrudType) extends CrudBridge {
    /**
     * Delete the instance of TheCrudType from the backing store
     */
    def delete_! : Boolean = in.delete_!

    /**
     * Save an instance of TheCrudType in backing store
     */
    def save : Boolean = in.save

    /**
     * Validate the fields in TheCrudType and return a List[FieldError]
     * representing the errors.
     */
    def validate: List[FieldError] = in.validate

    /**
     * Return a string representation of the primary key field
     */
    def primaryKeyFieldAsString: String = in.primaryKeyField.toString
  }

  /**
   * This method will instantiate a bridge from TheCrudType so
   * that the appropriate logical operations can be performed
   * on TheCrudType
   */
  protected implicit def buildBridge(from: TheCrudType): CrudBridge =
    new MyBridge(from)

  protected class MyPointer(in: MappedField[_, CrudType]) extends FieldPointerBridge {
    /**
     * What is the display name of this field?
     */
    def displayHtml: NodeSeq = in.displayHtml
  }

  /**
   * Based on a FieldPointer, build a FieldPointerBridge
   */
  protected implicit def buildFieldBridge(from: FieldPointerType): FieldPointerBridge = new MyPointer(from)


}


/**
 * A specialization of CRUDify for LongKeyedMetaMappers.
 */
trait LongCRUDify[CrudType <: KeyedMapper[Long, CrudType]] extends CRUDify[Long, CrudType] {
  self: CrudType with KeyedMetaMapper[Long, CrudType] =>
}