Learn Java-chapter 2 operator (Operator)

1. Assignment operator

= assigned value

eg

int cadence = 0;int Speed = 0;int gear = 1;

2. Basic mathematical operators

+ Plus (both sides are numeric variables or values for mathematical operations, one of which is a character variable or value as a JOIN operation)

-Minus

* Multiply

/except (two integers for division, ending rounding, Original:integer division rounds toward 0)

% take-up

3, unary operators

+ Indicates positive number

-Indicates negative numbers

+ + increment operation adds 1 each time. Before the variable is represented by +1, then the variable is used, after which the variable is used, and then +1

--the self-subtraction operation is reduced by 1 each time. Before the variable is represented by-1, and then the variable is used after the variable is used, and then 1

！ Logical operators, taking the inverse

int i = 3;i++;//prints 4system.out.println (i); ++i; Prints 5system.out.println (i);//Prints 6system.out.println (++i);//Prints 6system.out.println (i++);//Prints 7system.out.println (i);

4. Relational operators

= = Judgment Equality (the base type is judged by the value, and the reference type determines equality based on the address referenced by the object)! = is not judged equal to (IBID.) > Greater than>= greater than or Equa L to< less than<= less than or equal to

The above relational operators are typically used as a base type comparison, and object comparisons typically use the Equals method of the object.

5. Conditional operators

&& and

|| Or

int value1 = 1;int value2 = 2;if ((value1 = = 1) && (value2 = 2)) System.out.println ("value1 is 1 and value2 are 2 "); if ((value1 = = 1) | |    (value2 = = 1)) System.out.println ("value1 is 1 OR value2 is 1");

6. Type detection

instanceof

Used to determine whether an instance is an instance of a class (a class or subclass of a class or an interface ) .

Class instanceofdemo {    public static void main (String[]  args)  {         parent obj1 = new parent ();         parent obj2 = new child ();          system.out.println ("obj1 instanceof parent: "              +  (obj1 instanceof parent));         system.out.println ("obj1 instanceof child: "             +  (obj1 instanceof  Child));         system.out.println ("obj1 instanceof  myinterface:  "            +  (obj1  Instanceof myinterface)), &Nbsp;       system.out.println ("obj2 instanceof parent: "             +  (obj2 instanceof  Parent));         system.out.println ("Obj2 instanceof child:   "            +  (obj2 instanceof  child));         system.out.println ("obj2 instanceof  myinterface:  "            +  (obj2  Instanceof myinterface));    }} class parent {}class child  extends parent implements myinterface {}interface myinterface {}

Output:

Obj1 instanceof parent:trueobj1 instanceof child:falseobj1 instanceof myinterface:falseobj2 instanceof parent:trueobj2 instanceof Child:trueobj2 instanceof Myinterface:true

7. Displacement operator

<< left-shift arithmetic >> right-shift operation >>> unsigned right-shift operation & Bitwise AND ^ Bitwise XOR | Bitwise OR ~ bitwise inverse (non)

Learn Java-chapter 2 operator (Operator)