Executing Sun IdM XPress Rules from Java

Example Rule

As a simple example, let’s say we have a rule getUserAttribute that gets and returns a specified attribute – for example fullname – of a user identified by her accountId:

<Rule name="getUserAttribute">

<RuleArgument name="context" />

<RuleArgument name="accountId" />

<RuleArgument name="attrName" />

<defvar name="wsUser">

<invoke name="getObjectIfExists">

<ref>context</ref>

<s>User</s>

<ref>accountId</ref>

</invoke>

</defvar>

<invoke name="getAttribute">

<ref>wsUser</ref>

<ref>attrName</ref>

</invoke>

</Rule>

Executing Rules from Java

Let’s say this rule is stored in a configuration object of wsType EndUserLibrary whose name is MyCorp-UserRuleLibrary.
That is, the full name to our rule is MyCorp-UserRuleLibrary:getUserAttribute.
It takes only a few lines to execute this rule from Java. Let’s first create a Util class holding our method:

package com.mycorp.util.XpressUtil;

import java.util.Map;

import com.waveset.expression.ExState;

import com.waveset.object.LighthouseContext;

import com.waveset.object.Rule;

import com.waveset.util.WavesetException;

public class XpressUtil {

public static Object executeRule(LighthouseContext context,

String ruleName, Map args) throws WavesetException {

Rule rule = Rule.findRule(context.getCache(), ruleName);

ExState state = new ExState();

return rule.eval(state, args);

}

}

Now we can execute our XPress rule from Java:

import java.util.Map;

import java.util.HashMap;

import com.waveset.session.Session;

import com.waveset.session.SessionFactory;

import com.waveset.util.EncryptedData;

import com.mycorp.util.XpressUtil;

// somewhere in our java code...

EncryptedData encryptedPassword = new EncryptedData("configurator");

Session wsSess = SessionFactory.getSession("Configurator", encryptedPassword);

String ruleName = "MyCorp-UserRuleLibrary:getUserAttribute";

Map args = new HashMap();

args.put("context", wsSess);

args.put("accountId", "Configurator");

args.put("attrName", "fullname");

Object result = XpressUtil.executeRule( wsSess, ruleName, args );