Destructor questions

• How can I use Optional to return empty if there is any exception in the code in it?
• Key listener for composite?
• Is it possible to change Finish button text to Done in Wizard?
• How to add padding to drop down list that we get by clicking on spinner?
• How to replace one or more \ in string with just \?
• Is it possible a kill a command launched using system api in C? If not any alternatives?
• Is it possible to access environment variables in html file?
• How to ask user to unlock device on clicking notification action in android?
• Is there any difference between adb wait-for-device and adb wait-for-devices?
• BufferedReader.readLine blocks my program but BufferedReader.read() reads properly

Destructor answers