I encountered the following message repeatedly when trying to start SQL Developer from my installation of Oracle Database 11g Enterprise: Enter the full pathname for java.exe.
No matter how many times I browsed to the correct path, I kept being presented with the exact same dialog box. This was in Windows 7, and the solution was to right-click on the SQL Developer icon and select "Run as administrator". I then used this path:C:\app\用户名文件夹名称\product\11.1.0\db_1\jdk\jre\bin\java.exe