Mysterious newInstance method

Question

Hi, All.

This question is about the newInstance method and the call of missing classes(libraries) in run time.

First I show some code.

library: axis.jar, dom4j.jar jdk1.5, windowsXP

---

T.java

import java.io.StringWriter;

import org.apache.axis.utils.StringUtils;
import org.dom4j.DocumentHelper;
import org.dom4j.io.OutputFormat;
import org.dom4j.io.XMLWriter;


public class T {
public T() {
    System.out.println("constructor");
}

public void test() {
    System.out.println(StringUtils.unescapeNumericChar("1"));
}

public String getPrettyXML(String xml) throws Exception {
    System.out.println("getPrettyXML");
    StringWriter sw = new StringWriter();
    XMLWriter writer = null;
    try {
        OutputFormat format = OutputFormat.createPrettyPrint();
        org.dom4j.Document document = DocumentHelper.parseText(xml);
        writer = new XMLWriter(sw, format);
        writer.write(document);
    } catch (Exception e) {
        throw e;
    } finally {
        if (writer != null) {
            try {
                writer.close();
            } catch (Exception e) {
            }
        }
    }
    return sw.toString();
}

public void a() {
    System.out.println("a");
}

public static void main(String[] args) {
    new T().test();
}

}

---

T2.java

public class T2 {
public static void main(String[] args) throws Exception {
    System.out.println("T2");
    T t = (T) Class.forName("T").newInstance();     
}
}

---

Ok, here we go... run as (Of course, I'm run at the directory where T.class, T1.class is)

java T2

as you can see, the command does not have a class path.

==console==
T2
constructor

OK... Now delete

throw e

line at the catch block on the "getPrettyXML" method of T.

Ok, here we go.. run one more time without classpath

java T2

You can see below...

==console==
T2
Exception in thread "main" java.lang.NoClassDefFoundError: org/dom4j/io/OutputFormat
    at java.lang.Class.forName0(Native Method)
    at java.lang.Class.forName(Unknown Source)
    at T2.main(T2.java:5)

---

I like to know why the second case is fail. Only just because of "throw e" statement existence.

As far as I know, although the code has a missing classes part, it's OK if a missing classes code part isn't called in runtime. So the second case, because the getPrettyXML method is not yet called and just a default constructor is called by newInstance method, I think the ouput of the second case is same with the first case.

P.S. Here is my eclipse project. http://www.sharefile.org/showfile-2471/classscope.zip