Example of a random-number-generator function

Random number generator functions are one of several XPath 2.0 functions supported in model expressions in IBM® Business Monitor. Define random number generator XPath functions for use in monitor model XPath expressions.

The following code exemplifies the use of the random number generator user-defined XPath function:

import static com.ibm.wbimonitor.xml.expression.udf.XPathType.Indicator.One;

import java.math.BigDecimal;
import java.math.BigInteger;

import com.ibm.wbimonitor.xml.expression.udf.XPathFunction;
import com.ibm.wbimonitor.xml.expression.udf.XPathType;

public class Examples {
public static final String NAMESPACE = "http://www.jimbo.org/beverages/functions";

@XPathFunction(
namespaceName = NAMESPACE,
localName = "random", //$NON-NLS-1$
description = "(max) Returns a random integer on the interval [0, max). If max is the empty sequence 0 will be returned.",
isDeterministic = false,
isSelfContained = true
)
public static @XPathType(occurrenceIndicator = One) BigInteger randomNumber(final BigInteger max) {
if (max == null) return BigInteger.ZERO;
return new BigDecimal(max).multiply(new BigDecimal(Math.random())).toBigInteger();
}
}