Android - Quiz 15

How to sort an array?

• Array.sort()
• Arrays.sort()
• Collection.sort()
• System.sort()

Can an interface be final?

• Yes
• No

Which of this method of class StringBuffer is used to concatenate the string representation to the end of invoking string?

• concat()
• append()
• join()
• concatenate()

Which of these class is used to create an object whose character sequence is mutable?

• String()
• StringBuffer()
• String() & StringBuffer()
• None of the mentioned

When compiling, I get an Exception in thread main java.lang.NoClassDefFoundError:myprogram. What does this error mean?

• The program path is wrong.
• There is no main function
• No class declaration
• There is no public keyword at the beginning of the class declaration

Which of these class is related to all the exceptions that can be caught by using catch?

• Error
• Exception
• RuntimeExecption
• All of the mentioned

Which sentences is wrong when say about lateinit and lazy keyword

• lateinit if for non-null properties, it means no need to check null for it.
• lateinit can only be used with var (mutable) properties whereas lazy can only be used for val (immutable) properties.
• lateinit and lazy can work with primitive type.
• While using Singleton Pattern (Object Declaration in Kotlin) we should use lazy, as it will be initialized upon first use.

Do permission "Signature" protect level need user approve to use?

• Yes
• No

Which of the following are Android RecyclerView layout managers?

• GridLayoutManager
• RecyclingManager
• LinearLayoutManager
• CircularLayoutManager

Which of the following will directly stop the execution of a Thread?

• notify()
• notifyall()
• exits synchronized code
• wait()