hedera-web/js/db/result-set.js

111 lines
1.8 KiB
JavaScript

var Result = require ('./result');
/**
* This class stores the database results.
*/
module.exports = new Class
({
results: null
,error: null
/**
* Initilizes the resultset object.
*/
,initialize: function (results, error)
{
this.results = results;
this.error = error;
}
/**
* Gets the query error.
*
* @return {Error} the error or null if no errors hapened
*/
,getError: function ()
{
return this.error;
}
,fetch: function ()
{
if (this.error)
throw this.error;
if (this.results !== null
&& this.results.length > 0)
return this.results.shift ();
return null;
}
/**
* Fetchs the next result from the resultset.
*
* @return {Db.Result} the result or %null if error or there are no more results
*/
,fetchResult: function ()
{
var result = this.fetch ();
if (result !== null)
{
if (result.data instanceof Array)
return new Result (result);
else
return true;
}
return null;
}
/**
* Fetchs the first row from the next resultset as an object.
*
* @return {Object} the row if success, %null otherwise
*/
,fetchObject: function ()
{
var result = this.fetchResult ();
if (result instanceof Result)
return result.fetchObject ();
return null;
}
/**
* Fetchs the first row from the next resultset.
*
* @return {Array} the row if success, %null otherwise
*/
,fetchRow: function ()
{
var result = this.fetch ();
if (result !== null
&& result.data instanceof Array
&& result.data.length > 0)
return result.data[0];
return null;
}
/**
* Fetchs the first row and column value from the next resultset.
*
* @return {Object} the value if success, %null otherwise
*/
,fetchValue: function ()
{
var row = this.fetchRow ();
if (row instanceof Array && row.length > 0)
return row[0];
return null;
}
});