Chris,
Thanks a lot.
I did try the newest Hydrohub download and it worked with Java 8 for 2D outputs but it shows the same error for 3D outputs. Here is the code  in the datablock file I used.
<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<AEM3DOutput>
  <GlobalTime>
    <interval>288</interval>
  </GlobalTime>
    <globalVariable>HEIGHT</globalVariable>
    <globalVariable>TEMPERATURE</globalVariable>
    <globalVariable>DO</globalVariable>
     <Profile>
    <filename>profile.nc</filename>
    <location>13,5</location>
    <Time>
      <interval>288</interval>
    </Time>
  </Profile>
  
 <All3D>
     <filename>Temp.nc</filename>
     <variable>TEMPERATURE</variable>
 </All3D>
 <All3D>
     <filename>DO.nc</filename>
      <variable>DO</variable>
 </All3D>  
   <All3D>
     <filename>all.nc</filename>
     <variable>HEIGHT</variable>
     <variable>DO</variable>
     <variable>TEMPERATURE</variable>
 </All3D>
  
</AEM3DOutput>