John Cooper questions

• What is the difference in these two declarations?
• sorting and removing keys with null values
• Switch case - else condition
• Generate random numbers between two numbers
• If/else condition inside an Object
• Calculating Age in Months and days
• What is the use of return statement inside a function?
• remove HTML from a string (in JSON response)
• Why does a class implements Serializable interface? [duplicate]
• When to use flush() in java?

John Cooper answers