webui-aria2/js/libs/dojo/store/Memory.js.uncompressed.js
2012-05-01 19:52:07 +08:00

163 lines
4.9 KiB
JavaScript

//>>built
define("dojo/store/Memory", ["../_base/declare", "./util/QueryResults", "./util/SimpleQueryEngine"], function(declare, QueryResults, SimpleQueryEngine) {
// module:
// dojo/store/Memory
// summary:
// The module defines an in-memory object store.
return declare("dojo.store.Memory", null, {
// summary:
// This is a basic in-memory object store. It implements dojo.store.api.Store.
constructor: function(/*dojo.store.Memory*/ options){
// summary:
// Creates a memory object store.
// options:
// This provides any configuration information that will be mixed into the store.
// This should generally include the data property to provide the starting set of data.
for(var i in options){
this[i] = options[i];
}
this.setData(this.data || []);
},
// data: Array
// The array of all the objects in the memory store
data:null,
// idProperty: String
// Indicates the property to use as the identity property. The values of this
// property should be unique.
idProperty: "id",
// index: Object
// An index of data indices into the data array by id
index:null,
// queryEngine: Function
// Defines the query engine to use for querying the data store
queryEngine: SimpleQueryEngine,
get: function(id){
// summary:
// Retrieves an object by its identity
// id: Number
// The identity to use to lookup the object
// returns: Object
// The object in the store that matches the given id.
return this.data[this.index[id]];
},
getIdentity: function(object){
// summary:
// Returns an object's identity
// object: Object
// The object to get the identity from
// returns: Number
return object[this.idProperty];
},
put: function(object, options){
// summary:
// Stores an object
// object: Object
// The object to store.
// options: dojo.store.api.Store.PutDirectives??
// Additional metadata for storing the data. Includes an "id"
// property if a specific id is to be used.
// returns: Number
var data = this.data,
index = this.index,
idProperty = this.idProperty;
var id = (options && "id" in options) ? options.id : idProperty in object ? object[idProperty] : Math.random();
if(id in index){
// object exists
if(options && options.overwrite === false){
throw new Error("Object already exists");
}
// replace the entry in data
data[index[id]] = object;
}else{
// add the new object
index[id] = data.push(object) - 1;
}
return id;
},
add: function(object, options){
// summary:
// Creates an object, throws an error if the object already exists
// object: Object
// The object to store.
// options: dojo.store.api.Store.PutDirectives??
// Additional metadata for storing the data. Includes an "id"
// property if a specific id is to be used.
// returns: Number
(options = options || {}).overwrite = false;
// call put with overwrite being false
return this.put(object, options);
},
remove: function(id){
// summary:
// Deletes an object by its identity
// id: Number
// The identity to use to delete the object
// returns: Boolean
// Returns true if an object was removed, falsy (undefined) if no object matched the id
var index = this.index;
var data = this.data;
if(id in index){
data.splice(index[id], 1);
// now we have to reindex
this.setData(data);
return true;
}
},
query: function(query, options){
// summary:
// Queries the store for objects.
// query: Object
// The query to use for retrieving objects from the store.
// options: dojo.store.api.Store.QueryOptions?
// The optional arguments to apply to the resultset.
// returns: dojo.store.api.Store.QueryResults
// The results of the query, extended with iterative methods.
//
// example:
// Given the following store:
//
// | var store = new dojo.store.Memory({
// | data: [
// | {id: 1, name: "one", prime: false },
// | {id: 2, name: "two", even: true, prime: true},
// | {id: 3, name: "three", prime: true},
// | {id: 4, name: "four", even: true, prime: false},
// | {id: 5, name: "five", prime: true}
// | ]
// | });
//
// ...find all items where "prime" is true:
//
// | var results = store.query({ prime: true });
//
// ...or find all items where "even" is true:
//
// | var results = store.query({ even: true });
return QueryResults(this.queryEngine(query, options)(this.data));
},
setData: function(data){
// summary:
// Sets the given data as the source for this store, and indexes it
// data: Object[]
// An array of objects to use as the source of data.
if(data.items){
// just for convenience with the data format IFRS expects
this.idProperty = data.identifier;
data = this.data = data.items;
}else{
this.data = data;
}
this.index = {};
for(var i = 0, l = data.length; i < l; i++){
this.index[data[i][this.idProperty]] = i;
}
}
});
});