java的：转换二进制字符串为int [英] java: convert binary string to int

问题描述

我想一对夫妇二进制字符串的转换回int类型。然而，它并没有将我所有二进制字符串，留下了我的 java.lang.NumberFormatException 例外。
下面是我的测试code 3二进制字符串：

I'm trying to convert a couple of binary strings back to int. However it doesn't convert all my binary strings, leaving me a java.lang.NumberFormatException exception. Here is my test code with 3 binary string:

public class Bin {

    public static void main(String argvs[]) {
            String binaryString ;
            binaryString = Integer.toBinaryString(~0);
            //binaryString = Integer.toBinaryString(~1);
            //binaryString = "1010" ;
            int base = 2;
            int decimal = Integer.parseInt(binaryString, base);
            System.out.println("INPUT=" + binaryString + " decimal=" + decimal) ;
    }
}

如果我转换成1010它的伟大工程，但是当我尝试转换其他两个之一，我得到的异常。能向我解释的人这是为什么？

If I convert the "1010" it works great, but when I try to convert one of the other two I get the exception. Can someone explain to me why this is ?

干杯

推荐答案

从的http://docs.oracle.com/javase/1.5.0/docs/api/java/lang/Integer.html#toBinaryString(int) ：它的输入 toBinaryString（）方法转换成无符号整数值为参数加上2 ^{32 如果参数为负}的。

From http://docs.oracle.com/javase/1.5.0/docs/api/java/lang/Integer.html#toBinaryString(int) : the toBinaryString() method converts its input into the binary representation of the "unsigned integer value is the argument plus 2³² if the argument is negative".

从<一个href=\"http://docs.oracle.com/javase/1.5.0/docs/api/java/lang/Integer.html#parseInt(java.lang.String,%20int)\" rel=\"nofollow\">http://docs.oracle.com/javase/1.5.0/docs/api/java/lang/Integer.html#parseInt(java.lang.String,%20int) ：在 parseInt函数（）方法抛出 NumberFormatException异常如果的由字符串psented转口货值为$ P $是类型不是值 INT 的。

From http://docs.oracle.com/javase/1.5.0/docs/api/java/lang/Integer.html#parseInt(java.lang.String,%20int) : the parseInt() method throws NumberFormatException if "The value represented by the string is not a value of type int".

请注意，这两个 0〜和〜1 为负（-1和-2分别），所以将被转换成的二进制重新presentations 2 ³² -1和2 ³² -2分别两者都不可以重新在一值psented $ p $键入 INT ，所以造成了 NumberFormatException异常您看到。

Note that both ~0 and ~1 are negative (-1 and -2 respectively), so will be converted to the binary representations of 2³²-1 and 2³²-2 respectively, neither of which can be represented in a value of type int, so causing the NumberFormatException that you are seeing.

这篇关于java的：转换二进制字符串为int的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！