The best replacement for jpanel is jframe.

The best alternatives to jpanel are rated as following:
★★★★★  jframe
★★★★  canvas
★★★★  panel
★★★  jlabel
★★★  container
★★★  jcomponent
★  contentpane
★  jdialog
★  jscrollpane
★  jxpanel
★  canvas java
  jpanel

Your alternative for jpanel is not listed? Suggest!
Speaking about jpanel, one probably shouldn't forget about gridlayout.

Other search terms related to jpanel and their ratings are:
★★★★★ gridlayout
★★ gridbaglayout
★ jframe
★ jscrollpane
You have in mind a companion for jpanel and it is not yet here? Propose!



Google Trends

Scale is based on the average worldwide traffic of jpanel in all years. Click on graph for more.
jpanel
jframe
canvas