MQSeries.net :: View topic - Optimal way to use configuratoin information in mb

VishnuPrasadS · Posted: Wed Dec 04, 2013 8:09 pm Post subject:

I want to find optimal way to use configurational information in mb.
Please share your views.
Let me know if you have any other options

Options:
1. use java Properties class, query values from esql
2. store values from java to esql shared row variable
3. at first entry point store config values to MQRFH2.usr

2.1 how to initialize a shared esql row ?
options :
2.1.1. check if it is initialized for every message to flow
2.1.2. initialize using trigger from TimerNotification node

Issues with above said points
for option 1. Call from esql to java is not performance friendly
for option 2.1.1 Need to check if esql shared variable is populated for every message. If programmer forgets to include this check in any one entry point then it could result in null value access.
for option 2.1.2 Consider Input queues have 100's of messages. Now the execution group is reloaded. Execution Group has multi threaded flows. For first second or so, accessing the shared esql row will result in null value.
for option 3 Copy of all config values to MQRFH2.usr for every message is needed even if only few of them will be used.

Details of above said points are mentioned below.
--------------------------------------------------------
1.

// java static block to load values from file to hashmap
static {
InputStream is = null;
is = new FileInputStream(new File(FILE_NAME));
prop = new Properties();
prop.load(is);
is.close();
}

public static synchronized String getProperty(String key) {
if (key == null)
return null;
return prop.getProperty(key);
}

--esql can access values in java hashmap using this procedure
CREATE PROCEDURE GetPropertyValue ( IN key char) returns char
LANGUAGE JAVA
EXTERNAL NAME "a.b.PropertyLoader.getProperty";

declare value char GetPropertyValue('......');

--------------------------------------------------------
2.1.1

CREATE PROCEDURE PopulateSharedEsqlVariable ( IN esqlRow reference) returns boolean
LANGUAGE JAVA
EXTERNAL NAME "a.b.PropertyLoader.PopulateSharedEsqlVariable";
--

declare sv shared row;
declare loaded shared boolean false;

CREATE FUNCTION LOAD_SHARED_ESQL_VARIABLES()
BEGIN
if loaded is false then
set loaded = PopulateSharedEsqlVariable(sv);
end if;
END;
--

public static synchronized Boolean PopulateSharedEsqlVariable(MbElement esqlRow) {
try {
Set keys = prop.keySet();
for (Object key : keys) {
.....MBElement....Create...(esqlRow, key.toString()).setValue(prop.getProperty(key.toString()));
}
return true;
} catch (MbException e) {
throw new RuntimeException(e);
}
}
}

LOAD_SHARED_ESQL_VARIABLES should be called immediately after all "entry points of flow".
Then acess to configurational values is possible as

declare value char sv.configKey;

--------------------------------------------------------
2.1.2

methods mentioned in 2.1.1 will be used
but LOAD_SHARED_ESQL_VARIABLES() will be called only when the execution group is reloaded or only during bar deployment.
To achieve this a TimerNotification node is connected to a ESQL compute node and this compute node will invoke LOAD_SHARED_ESQL_VARIABLES()

Property of TimerNotificatoin node
Operation mode : Automatic
Timeout Interval : 86400 or any other large value

--------------------------------------------------------
3.

call PopulateSharedEsqlVariable(OutputRoot.MQRFH2.usr.ConfigLoc);

--Then acess to configurational values is possible as
declare value char InputRoot.MQRFH2.usr.ConfigLoc.configKey;

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