Common types in java and common types in java

Common types in java and common types in java

1. Convert the String to an integer (String ---> int)
Method 1:
(1) int I = Integer. parseInt (String s );

Among them, (1) is actually the number we often use to convert s to a 10-digit number. In fact, the default is to call int I = Integer. parseInt ("123", 10 );

(2) I = Integer. parseInt (String s, int radix );

The range of radix is 2 ~ If the value range is greater than 36, an exception is thrown. The length of s cannot exceed 7. Otherwise, an exception is thrown.

Method 2:

Int I = Integer. valueOf (my_str). intValue ();

Note: The methods for converting a string to Double, Float, and Long are similar to those above.

2. How to convert an integer to a String (int ---> String)

(1) String s = String. valueOf (I );
(2) String s = Integer. toString (I );
(3) String s = "" + I;
Note: Convert Double, Float, and Long into stringsSimilar to the above.