16) Arithmetic operators:
Arithmetic operators are used to perform arithmetic operations
like addition,subtraction etc.Arithmetic operators are called binary operator because it acts on two operands at a time.
Here are the list of arithmetic operators in java:
To find cube root of a number in java use cbrt method of Math class.
|public static double cbrt(double a)
If argument is Nan the result is Nan. Continue reading
To find square root of a number in java use sqrt method of Math class. Continue reading
To convert negative number to positive in java use abs function of Math class.
Abs : Abs returns the the absolute value of a number.
ABS of positive number will return positive number.
ABS of negative number will return positive number. Continue reading
11) ArrayList :
Arraylist is similar to array but arraylists are dynamic in nature except arraylist objects grow and shrink as needed.Arraylist is an resizable array.Adding and deleting elements in array should be manually.Developer has to implement logic to add and delete elements.
Using arraylist adding and removing elements is made easier with help of add() and remove() methods. Continue reading
Annotations are meta tags.Annotations allows us to add metadata to classes,methods,fields,packages.Annotations are not part of the code and annotation dont directly impact our code. These meta data can be used by java tools both at compile time at run time.
Annotations have the following uses :
- Information for the compiler : Annotations provide information to the compiler to detect errors or surpress warnings.
- Compiletime and runtime processing : Annotations provide information to the software tools to generate code,xml files and so forth.
Here are some of the predefined or built in annotations :
We can create our annotations. Annotations are declared with @. Continue reading
Explain Order By clause with examples?
- Order By clause is used to sort the data retrieved using query.
- Order By Clause sorts the data in ascending or descending order.
- Order By Clause must follow either where or from clause. Continue reading
Difference between where clause and Having clause with example
| Where clause
|| Having clause
|Where clause can be used with select,update,delete
||Having clause is used for only select query.
|Where clause is applied on each and every row.
||Having clause is applied on group of rows. Continue reading
Explain Having clause in sql?
1) Having clause is used to filter group of rows.
2) Having clause is placed after group by clause.
3) Having clause is used to compare group values like sum,count,max,min,avg etc.
4) Having clause is used only for select query. Continue reading