I opened a table and selected a CLOB-field with a large text in it.
My screen was filled with a preview of the contents and the RAM was filled to the max by the sqldeveloper process to the point of unusability of my pc (Win7_x64 with 4GB RAM).
In a tweet-exchange with Jeff Smith he determined that the problem is a preview not limited to a substring but instead showing everything.
At his request I am posting this in the forum (hopefully in the correct way ;-) ) as a note.
In Windows the java-version is:
SetJavaHome C:\Program Files\Java\jdk1.6.0_37
java version "1.6.0_37"
Java(TM) SE Runtime Environment (build 1.6.0_37-b06)
Java HotSpot(TM) 64-Bit Server VM (build 20.12-b01, mixed mode)
Edited by: Menno Harzing on 3-apr-2013 11:51
I've tried the same 'hover-over-CLOB' in a CentOS 6(-x86_64)-environment with the latest SQL Developer connected to the same environment.
When I leave the field the hover-field the behaviour is as expected: the hover-field disappears and there are no residual problems.
$ java -version
java version "1.6.0_24"
OpenJDK Runtime Environment (IcedTea6 1.11.9) (rhel-220.127.116.11.9.el6_4-x86_64)
OpenJDK 64-Bit Server VM (build 20.0-b12, mixed mode)