<programlisting/> elements must contain no newlines at beginning or end.
The following is an example of what not to do:

    <programlisting><![CDATA[
package com.foo.bar;

class XFoo implements Foo<X> {
}]]>
    </programlisting>

This leaves newlines at the beginning and end of the programlisting
panel within the PDF. Instead, do it like this:

    <programlisting><![CDATA[package com.foo.bar;

class XFoo implements Foo<X> {
}]]></programlisting>