在我们的情况下,我们不得不从数据库加载查找值,我们解决了这个如下:
- 有一个通道部署脚本加载频道部署到全局地图时的查找值。
- 有一个全局模板函数,允许您从这个全球地图查找值。
- 在过滤器和翻译中使用全局模板函数。
注意:在我们的例子中,每个键可以有两个值与它关联。如果我们不使用两者,只需在数据库查询中将第二个设置为null即可。
要加载的世界地图的地方这在频道中的部署脚本(需要定制):
// This script executes once when the mule engine is started
// You only have access to the globalMap here to persist data
var sqlDBDriver = 'net.sourceforge.jtds.jdbc.Driver';
var sqlDBName = 'jdbc:jtds:sqlserver://databaseserver/databasename';
var sqlDBDUser = 'username';
var sqlDBPassword = 'password';
function PopulateLookup (sqlQuery, globalMapName)
{
logger.info('Loading lookup table values in the deploy script: ' + globalMapName);
var dbConn = DatabaseConnectionFactory.createDatabaseConnection(sqlDBDriver, sqlDBName, sqlDBDUser, sqlDBPassword);
var rs = dbConn.executeCachedQuery(sqlQuery);
dbConn.close();
var arr = new Array();
while(rs.next())
{
var obj = new Object();
obj.LeftValue = rs.getString('LeftValue');
obj.RightValue1 = rs.getString('RightValue1');
obj.RightValue2 = rs.getString('RightValue2');
arr.push(obj);
}
globalMap.put(globalMapName, arr);
}
PopulateLookup('SELECT keyColumn as LeftValue, Value1 as RightValue1, Value2 as RightValue2 FROM tableName', 'GlobalMapName');
// Repeat above line as needed for each lookup you need
return;
为了访问您使用下面的函数作为全局模板这些值。
function FindLookupValueWithDefault (LookupGlobalMapName, LeftValue, DefaultValue1, DefaultValue2){
/***********************************************************************************************
DESCRIPTION: Retrieves lookup table values from the global map and uses the input values to return output values
PARAMETERS:
LookupGlobalMapName - name of the lookup table in the Global Map
LeftValue - The value to look up
DefaultValue1 - the first default value if a match was not found
DefaultValue2 - the second default value if a match was not found
RETURNS:
An object containing the replacement value and associated OID if applicable
REMARKS:
************************************************************************************************/
// Retrieve the previously matched item from the globalmap
// We do this to save time and not look through a huge lookup table tons of times
// unless we absolutely have to
var prevItem = globalMap.get(LookupGlobalMapName + '-Previous');
// This is the same item requested for this globalmap name - just return the previous value
if (prevItem != null && prevItem.LeftValue == LeftValue) {
return prevItem;
}
//
// If we reach this point the previous item either did not exist or did not match
//
// Retrieve the array with lookup objects from the globalmap and search for the matching value
var arr = globalMap.get(LookupGlobalMapName);
var obj = new Object();
obj.LeftValue = LeftValue;
obj.RightValue1 = DefaultValue1;
obj.RightValue2 = DefaultValue2;
for each (item in arr)
{
var pattern=new RegExp("^" + item.LeftValue + "$");
var result = pattern.test(LeftValue);
if (pattern.test(LeftValue))
{
obj = item;
break;
}
}
// Store the previous value in the globalmap
globalMap.put(LookupGlobalMapName + '-Previous', obj);
// Return the object we found or created
return obj;
}
的代码样本访问该值:
var myObject = FindLookupValueWithDefault('GlobalMapName', 'LookupValue', 'DefaultValue1', 'DefaultValue2');
if (myObject != null)
{
var value1 = myObject.RightValue1;
var value2 = myObject.RightValue2;
}
您的里程可能会有所不同......但现在这已经为我们带来最多。
谢谢, Frans de Wet
谢谢杰森;我从你的博客文章中学到了很多东西。发布技巧的荣誉!我有实施,我会尽可能在问题中发布。再次感谢! – 2009-05-30 01:42:13