If the Oracle SQL Developer crashing on startup on your computer, you can follow the solutions mentioned in this post to resolve the issue.

How to Connect to DB2 With SQL Developer. The Oracle SQL Developer tool can connect to databases other than Oracle, including MySQL, Microsoft SQL Server and DB2. The SQL development environment ...

Open Oracle Developer. Click "View" and then click "Dbms Output." Click the green "+" sign in the window that opens and select the database connection from which you want output.