Data type conversion
1, automatic type conversions
byte,short,char-->int-->long-->float-->double
(1) byte and the byte, short and short, char and char operation, upgraded int
(2) byte and short, byte char and mixing operation, upgraded int
(3) mixing all types of operation, automatically upgraded to the largest type
(4) Boolean not participate in any type of conversion
(5) Once all types "+" stitching and string, are the result string
2, cast
double-->float-->long-->int-->byte,short,char
(1) risk, may overflow or loss of precision
(2) the small memory may need to cast a large range of types
(3) Boolean not participate in any type of conversion
(4) string does not participate in cast
Operators
First, arithmetic operators
+ (Plus), - (minus (), *, /,%, + (plus), - (negative), +, -
Second, the assignment operator
Basic operators: =
Extended operator: + =, - =, / =, = ........ *
Third, the comparison operator
The results are only two expressions, true and false, usually as a condition
Fourth, the logical operators
&、|、^、！、&&、||
V. conditional operator
Conditional expression? The resulting expression 1: Expression 2 results
Six, bitwise operators
(1) left <<: left several times, the equivalent of several square multiplied by 2
(2) >> right: the right times, divided by 2 is equivalent to several parties (up to see what is left of the most significant bit)
(3) >>> unsigned right: the difference between right and, regardless of why the highest, left several missing several fill 0
(4) & Bitwise AND: all 1 1
(5) or bit /: 1 of 1
(6) ^ bitwise XOR: 1 is different from
(7) bitwise ~: every inversion, becomes 0 becomes 0 1,1