java中字符串与数字的互相转换

String str1 = "123";
int num = 12;
//字符串转化为数字
int tranToNum =Integer.parseInt(str1, 16);
//16表示的是16进制，也可以是其他进制，不写则默认为10进制

//数字转化为字符串
String tranToStr = String.valueOf(num);
//通过包装类来实现

String str = "" + num;
//通过空字符串+数字

String str = (String) num;
//强制类型转换

//Jdk里String. valueOf(Object)源码如下：
/**
*
* Returns the string representation of the Object argument.
* @param   obj   an Object.
* @return if the argument is null, then a string equal to
* “null”; otherwise, the value of
* obj.toString() is returned.
* @see    java.lang.Object#toString()
*/

public static String valueOf(Object obj) {
return (obj == null) ? “null” : obj.toString();
}