public class Testfun {

public static void main(String[] args) {

// (一)跨Number父类的类型转换

// 1、str转int => Integer.parseInt(s1)

String s1 = "19";

int i2 = Integer.parseInt(s1);// 数字str转化为对标的int

System.out.println("++i2=" + (++i2));

// 2、int转str => Integer.toString(i3)

int i3 = 27;

String s4 = Integer.toString(i3);

System.out.println("s4=" + s4);

// 3、浮点转int => (int) d5

double d5 = 21.6;

int i6 = (int) d5;

System.out.println("i6=" + i6);

// 4、int转浮点 => (double) i7

int i7 = 60;

double d8 = (double) i7;

System.out.println("d8=" + d8);

// (二)同Number父类的类型转换

System.out.println();

Integer i9 = new Integer("17");

System.out.println(i9.intValue()); // 数字str转为int => i9.intValue()

System.out.println(i9.shortValue());// 数字str转为short => i9.shortValue()

System.out.println(i9.byteValue());// 数字str转为byte => i9.byteValue()

System.out.println();

// int转str(不同进制形式的str)

System.out.println(Integer.toString(456)); //获取10进制str

System.out.println(Integer.toBinaryString(456)); //获取2进制str

System.out.println(Integer.toHexString(456)); //获取16进制str

System.out.println(Integer.toOctalString(456)); //获取8进制str

}

}