String转int
String str = "123";
int a = Integer.parseInt(str);
System.out.println(a);
Integer b = Integer.valueOf(str);
System.out.println(b);
int c = Integer.valueOf(str).intValue();
System.out.println(c);
int转化为String
int i = 123;
String s = String.valueOf(i);
System.out.println(s);
String s2 = i + "";
System.out.println(s2);
String s3 = Integer.toString(i);
System.out.println(s3);