MangoDriod

Most people consider the collection as the root interface of Collections Framework and it is true to a great extent but another part of Collections Framework is Map Interface, we will see that later, Most Common methods which are applicable to all collections are defined in this interface for example add() to add an element, size() to get the size and much more, below is a table of most common methods. Hierarchey of the Collection Interface. The Parent of Collection Interface is Iterator Interface and the Collection is base class for List Interface, Set Interface and Queue Interface, the respective classes which impliments either of the sub classes will also implement the defined methods from the Collection Interface, below are some of the commonly used methods. Defined Methods: Method Description add() This method returns a Boolean value true if it inserts the specified element in this collection.

Gist: An array list can store individual objects by following insertion order, here the initial capacity is 10 by default but can be modified as per the requirement, once the array list reaches its load factor then internal all the elements of the current array is copied to a new array with the new capacity and the reference variable will now be referring to this new array list and the old array will be dealt by the garbage collector. Hierarchical order Type of constructors Empty argument constructor or the default constructor is the same as invoking any other object here a new ArrayList is created with a default size of 10. Below is the most commonly used constructor by beginners and others alike. ArrayList array = new ArrayList(); //array has a capacity of 10 The default constructor above will allot only 10 slots but if you want the initial size to be 20 or 1000 you can do so with the following constructor this is ideal w

Difficulty : EASY Problem : Maria plays college basketball and wants to go pro. Each season she maintains a record of her play. She tabulates the number of times she breaks her season record for most points and least points in a game. Points scored in the first game establish her record for the season, and she begins counting from there. Visual representation of the table Game Score Minimum Maximum Count Min Count Max 0 12 12 12 0 0 1 24 12 24 0 1 2 10 10 24 1 1 3 24 10 24 1 1 Ouput : [1 , 2] Imporant Points to note We canculate the record determining her performance on Game 0(which is highlited in green) which will the value of minimum and maximum. We change the value of maximum

1. Overview: A literal key indicates the compiler how to interpret the value of the given data type, for numbers we can calculate the value by using Octal representation or hexadecimal representation but just typing out a hexadecimal value to an int will throw us an error because the compiler has no idea how to handle it but if we assign the java specified prefix for the required bases with some literals then the compiler will not throw us any error as it understands how to interpret the value.  Base Litrals Values Example Eg. Value Decimal none 0-9 int x = 10; x is 10 Octal 0 (zero) as the prefix 0-7 int x = 12; x is 10 Hexadecimal 0x or (zero) along with an x 0-9 and a-f or A-F int x = 0XA; x is 10 Binary or Base(2) Allowed Digits 0 and 1 int i = 10; and now the variable i has value 10. int n = 12

2. Overview: There are eight primitive data types byte, short, int, long, float, double boolean, char. These eight data types store values as raw instead of Objects these primitives help to save memory to a great extent and simplify other processes as they are directly stored in the stack. Data Type Size(in bits) Minimum Range Maximum Range byte 8 -128 127 short 16 -32768 32767 int 32 -2147483648 2147483647 long 64 -9223372036854775808 9223372036854775807 float 32 -3.4e38 to -1.4e-45 1.4e-45 to 3.4e38 double 64 -1.8e308 to -4.9e-324 4.9e-324 to 1.8e308 boolean 1 - - char 16 space 65535 byte A byte has the capacity of 8 bits or 1 byte and it can store numbers between -2 7 and 2 7 -1 or simply -128 to 127. This is very useful while deali

Naming Conventions in Java As the movies are rated G, PG, U, A depending on the age restriction and by just gazing through the rating our parents decide the movie to watch together, or a book with diffrent labels to keep track of the sections and just by seeing them we know what they represent, the same labeling method has been introduced by Java team to diffrenciate variables, methods, classes, constants etc.. and we will be going through them all here. Type Naming Convention Example Variables Must start with a lower case and every other word capitalized int counter; Constants Must all be upper case and _ for diffrenciating every other word final int MAX_HEALTH = 100; Methods Must start with a lower case and every other word capitalized. can be distingiused from the variable by the () next to the method name void printNum(){..} Class Must start an upper case letter and every other word must