java之学习int和String的相互转换

package com.ifenx8.study.array;
package com.ifenx8.study.array;
 public class Demo_Integers { 
/*** A:int -- String 
* a:和""进行拼接
 * b:public static String valueOf(int i)
 * c:int -- Integer -- String(Integer类的toString方法())
 * d:public static String toString(int i)(Integer类的静态方法)
* B:String -- int 
* a:String -- Integer -- int 
* public static int parseInt(String s) 
*/ 
public static void main(String[] args) {
 //demo1();//int -- String 
//string---int String s = "100";
 Integer i = new Integer(s); 
int i2 = i.intValue();
 System.out.println(i2); 
int i3 = Integer.parseInt(s);
 System.out.println(i3);
 } 
public static void demo1() { 
int i = 100; 
String s = i + "";//通过和字符串拼接转成字符串 
System.out.println(s); 
Integer i2 = new Integer(i);//先转成Int的包装类Integer 
String s2 = Integer.toString(i);//通过toString转成字符串 
System.out.println(s2); 
String  s3 = Integer.toString(i);//静态方法直接类名点调用 
System.out.println(s3); 
String s4 = String.valueOf(i);//string类直接调用 System.out.println(s4); 
} 
}