\begin{figure}[htbp]
  \begin{center}
    \leavevmode
    \epsfysize0.93\textheight
    \epsfbox{eps/constantpool.eps}
    \caption{UML diagram for the ConstantPool API}\label{fig:umlcp}
  \end{center}
\end{figure}

\begin{figure}[ht]
  \begin{center}
    \leavevmode
    \epsfysize0.93\textheight
    \epsfbox{eps/instructions.eps}
    \caption{UML diagram for the Instruction API}\label{fig:umlinstr}
  \end{center}
\end{figure}