Commons Lang、Validate.isTrue()

everyday Java 
import org.apache.commons.lang.Validate;

public class C2009051100 {
    public static void main(String[] args) {
        Validate.isTrue(true,  "foo", "Hoge");

        Validate.isTrue(false, "foo", "Hoge");
    }
}

で、

Exception in thread "main" java.lang.IllegalArgumentException: fooHoge
	at org.apache.commons.lang.Validate.isTrue(Validate.java:75)
	at C2009051100.main(C2009051100.java:8)