在我們的情況下,我們不得不從數據庫加載查找值,我們解決了這個如下:
- 有一個通道部署腳本加載頻道部署到全局地圖時的查找值。
- 有一個全局模板函數,允許您從這個全球地圖查找值。
- 在過濾器和翻譯中使用全局模板函數。
注意:在我們的例子中,每個鍵可以有兩個值與它關聯。如果我們不使用兩者,只需在數據庫查詢中將第二個設置爲null即可。
要加載的世界地圖的地方這在頻道中的部署腳本(需要定製):
// 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;
爲了訪問您使用下面的函數作爲全局模板這些值。
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;
}
的代碼樣本訪問該值:
var myObject = FindLookupValueWithDefault('GlobalMapName', 'LookupValue', 'DefaultValue1', 'DefaultValue2');
if (myObject != null)
{
var value1 = myObject.RightValue1;
var value2 = myObject.RightValue2;
}
您的里程可能會有所不同......但現在這已經爲我們帶來最多。
謝謝, Frans de Wet
謝謝傑森;我從你的博客文章中學到了很多東西。發佈技巧的榮譽!我有實施,我會盡可能在問題中發佈。再次感謝! – 2009-05-30 01:42:13