下面是一段我自己设计的代码，目的是为了了解java.lang.Byte
- Java code
public class Tbyte{ public static void main(String args[]){ Byte b1=new Byte("a"); int i1; i1=b1.intValue(); System.out.println(i1); }}虽然编译通过，但运行结果出现了下面的文字
--------------------Configuration: <Default>--------------------
Exception in thread "main" java.lang.NumberFormatException: For input string: "a"
at java.lang.NumberFormatException.forInputString(NumberFormatException.java:48)
at java.lang.Integer.parseInt(Integer.java:449)
at java.lang.Byte.parseByte(Byte.java:151)
at java.lang.Byte.<init>(Byte.java:325)
at Tbyte.main(Tbyte.java:3)
Process completed.
我不知道为什么会这样，求解释啊........
------解决方案--------------------------------------------------------
- Java code
public class test { public static void main(String args[]) { Byte b1 = new Byte((byte)'a'); int i1; i1 = b1.intValue(); System.out.println(i1); }}
------解决方案--------------------------------------------------------
- Java code
String str = "127";//取值范围："-128","-127",...."-2","-1","0","1","2",....,"126","127"Byte b1 = new Byte(str);//因为它只有八个二进制位，十进制形式为大于-128小于127int i1;i1 = b1.intValue();/*Constructs a newly allocated Byte object that represents the byte value indicated by the String parameter. The string is converted to a byte value in exactly the manner used by the parseByte method for radix 10. */