Any interface can be functional interface, not merely those that come with Java. To declare your intention that an interface is functional, use the@FunctionalInterfaceannotation. Although not necessary, it will cause a compilation error if your interface does not satisfy the requirements (ie. one ...
QUESTION 1. Which of these is not included in a class diagram of an object class? The parent class The class name The methods The attributes QUESTION 2. To create a subclass, which Java keyword do you What does a double reference (&&) in C++ mean?
represent parenthetical grouping e.g., python allows us use indentation instead although this might not work too great if we had multiple levels involving lots of tiny sub-sections as there just wouldn't be enough visual clarity. what are the benefits of using parentheses in programming languages...
Java escape sequences can be placed in a string literal in three ways:Standard escapes with \b \f \n \r \t \” \’ : These represent the standard control characters BS, FF, NL, CR, TAB and the double and single quote. Octal escapes with \0 to \377 : These represent a single ...
Abstract classes are useful when you want to create a generic type that is used as a superclass for two or more subclasses, but the superclass itself does not represent an actual object. For example: As in case of Shape class which we need for inheritance and polymorphism but want only ...
Security: ID does not contain sensitive information. orderly increment: If you want to store the ID in the database, the order of the ID can improve the database write speed. And, in many cases, we are likely to sort directly by ID. ...
Aggregate operations enable you to perform functional-style operations on streams of elements, in particular, bulk operations on collections, such as sequential or parallel map-reduce transformations. Date-Time APIs enable you to represent dates and times and manipulate date and time values. They supp...
Primitiveor built-in data types are used to represent simple data values, including characters, integers, void, float and double data. Derived data types are derived from the primitive data types. They include arrays, pointers and functions. All three are important because they help programmers to...
How did Python find 5 in a dictionary containing 5.0? Python does this in constant time without having to scan through every item by using hash functions. When Python looks up a key foo in a dict, it first computes hash(foo) (which runs in constant-time). Since in Python it is requir...
The singleton is a popular and useful design pattern. The Java language does not provide a direct way to specify it at the language level; rather, it is the responsibility of the developer to implement it in Java source. Scala, on the other hand, provides a clear and convenient way to ...