计算一个二进制或者十进制的数的原码,反码和补码

import java.util.Scanner;

publicclass RadixChange

{

staticint byteNumber = 8;

// 将输入的操作数转换成八位二进制有符号整数,即得到这个数的原码；

publicstatic String decimalToBinary(String operand, int choice) {

String opeString = " " + operand;

String returnVal = null;

opeString = opeString.trim();

// char [] src={'0','0','0','0','0','0','0'};

if (choice == 0)

{

returnVal = Integer.toString(

new Integer(operand).intValue(), 2);

}

else

{

returnVal = opeString;

}

/**

* 将二进制数据用八位二进制原码表示

*/

// 如果是有符号二进制

if (choice == 1)

{

if (returnVal.codePointAt(0) == 48)

for (int i = returnVal.length(); i

{

returnVal = "0" + returnVal;

}

else

{

returnVal = returnVal.substring(1);

for (int i = returnVal.length(); i

{

if (i == byteNumber - 1)

returnVal = "1" + returnVal;

else

{

returnVal = "0" + returnVal;

}

}

}

return returnVal;

}

// 如果是十进制

else

{

if (Integer.parseInt(operand) > 0)

for (int i = returnVal.length(); i

{

returnVal = "0" + returnVal;

}

else

{

returnVal = returnVal.substring(1);

System.out.println(returnVal);

for (int i = returnVal.length(); i

{

if (i == byteNumber - 1)

{

returnVal = "1" + returnVal;

continue;

}

else

{

returnVal = "0" + returnVal;

}

}

}

}

return returnVal;

}

publicstatic String getComplement(String trueForm)

{

String complement = " ";

String charSequence = " ";

// 暂时存放得到的反码值

int[] temp = newint[byteNumber];

int flag = 0;

/**

* 如果操作数为整数，原值返回

*/

// 字符型常量'0'所对应的unicode码是48

if (trueForm.codePointAt(0) == 48)

{

System.out.println("反码是" + trueForm);

return trueForm;

}

else

{

for (int i = 0; i < trueForm.length(); i++)

{

if (i == 0)

{

temp[i] = trueForm.codePointAt(i) - 48;

continue;

}

else

{

if (trueForm.codePointAt(i) == 48)

temp[i] = 1;

else

{

temp[i] = 0;

}

}

}

}

for (int i = temp.length - 1; i >= 0;)

{

complement = temp[i] + complement;

i--;

}

// 此时complement的值是反码

complement = complement.trim(); // 去掉空格

System.out.println("反码是" + complement);

for (int i = 0; i

{

if (i == 0)

charSequence = "1" + charSequence;

else

{

charSequence = "0" + charSequence;

}

}

charSequence = charSequence.trim();

complement = stringLineAdd(complement, charSequence);

return complement;

}

// 两个二进制进行相加运算

publicstatic String stringLineAdd(String complement,

String charSequence)

{

String resultString = " ";

int flag = 0; // 标志进位符号，为0表示不进位，1表示进位

int i = complement.length() - 1;

while (i >= 0)

{

if (flag == 0)

{

int temp = complement.codePointAt(i)

+ charSequence.codePointAt(i) - 96;

if (temp >= 2)

{

temp = temp - 2;

flag = 1;

}

else

{

flag = 0;

}

resultString = temp + resultString;

}

else

{

int temp = complement.codePointAt(i)

+ charSequence.codePointAt(i) + 1 - 96;

if (temp >= 2)

{

flag = 1;

temp = temp - 2;

}

else

{

flag = 0;

}

resultString = temp + resultString;

}

i--;

}

resultString = resultString.trim();

return resultString;

}

publicstaticvoid main(String[] args)

{

System.out.println("输入你要计算的操作数，同时标注你所输入的操作数是十进制还是二进制，"

+ "如果是十进制紧随操作数后跟上" + ",0反之为,1");

System.out.println("示例输入：121,0");

String inputString = new Scanner(System.in).next();

String[] arrayStrings = inputString.split(",");

String returnVal = decimalToBinary(arrayStrings[0],

new Integer(arrayStrings[1]).intValue());

System.out.println("原码是" + returnVal);

System.out.println("补码是" + getComplement(returnVal));

}

}