java operators & concatenation

Operators
used to perform operations on variables or values

Order of execution(left to right)
Parenthesis - Arithmetic - Relational - Logical

Arithmetic
* / % + - are the arithmetic operators . executes in from left to right order .returns number value.
Eg :
Int i=5; int j=9; Int sum=i+j; Int sub=i-j; Int mul=i*j; Int div=i/j;

Relational
greaterThan ,lessThan, lessThanEqualsTo, greaterThanEqualsTo, doubleEquals , notEquals are the relational operators . returns Boolean value.

Eg :Int i=9; int j=7;
If(I gt j){ System.out.println(“I is bigger”); }
If(I lt j){ System.out.println(“j is bigger”); }
If(i==j){ System.out.println(“both are same”); }

Logical
&&(and) ,||(or), !(not) are logical operators .returns Boolean result
true && true returns true true || true returns true
false && true returns false false|| true returns true
true && false returns false true || false returns true
false && false returns false false || false returns false

Concatenation
“+” operator is used to concatenate two strings, or string & number , or string & character etc .
“10”+20=”1020”;
“10”+c=”10c”;
10+’a’=”10a”;
10+20+”30”=”3030”


Increment operator (++) is used to increase an integer by 1
Decrement operator (--) is used to decrease an integer by 1
Eg: ++I (pre-increment), --I ( pre-decrement) , i++(post-increment) ,i—(post-decrement)

Int i=7; System.out.println(“++I value is ” + ++I +” i++ value is “+ i++);
Int i=7; System.out.println(“--I value is ” + --I +” i-- value is “+ i--);