JAVA实现二进制和16进制之间的互相转换，8进制同理，附带异或操作实现

public static String bin2Hex(String binStr) {
		int deci = Integer.valueOf(binStr,2);
		return Integer.toHexString(deci);
	}
	
	public static String hex2Bin(String hexStr) {
		int deci = Integer.valueOf(hexStr,16);
		return Integer.toBinaryString(deci);
	}

public static void main(String args[]) {
		String str = "f012";
		System.out.println(hex2Bin(str));
		System.out.println(bin2Hex("01011011"));
	}

运行结果：

1111000000010010
5b

很easy

8进制同理，转换

可是以上方法的缺陷是，16进制或2进制串非常大时就转换失败，以下给出通用方法：

public static String bin2Hex(String binStr) {
		StringBuffer temp = null;
		while (binStr.length() % 4 != 0) {
			temp = new StringBuffer(binStr);
			temp.insert(0, "0");
			binStr = temp.toString();
		}
		StringBuffer sb = new StringBuffer();
		int deci = 0;
		for (int i = 0; i <= binStr.length() - 4; i += 4) {
			deci = Integer.valueOf(binStr.substring(i, i + 4), 2);
			sb.append(Integer.toHexString(deci));
		}
		return sb.toString();
	}

public static String hex2Bin(String hexStr) {
		StringBuffer sb = new StringBuffer();
		int deci = 0;
		StringBuffer temp = null;
		for (int i = 0; i < hexStr.length(); i++) {
			deci = Integer.valueOf(hexStr.charAt(i) + "", 16);
			temp = new StringBuffer(Integer.toBinaryString(deci));
			while (temp.length() < 4) {
				temp.insert(0, "0");
			}
			sb.append(temp);
		}
		return sb.toString();
	}

顺带来个异或操作：

public static String xor(String binStr1, String binStr2) {
		int len1 = binStr1.length();
		int len2 = binStr2.length();
		StringBuffer sb = new StringBuffer();
		if (len1 != len2) {
			return null;
		}
		for (int i = 0; i < len1; i++) {
			if (binStr1.charAt(i) == binStr2.charAt(i)) {
				sb.append("0");
			} else {
				sb.append("1");
			}
		}
		return sb.toString();
	}

public static void main(String args[]) {

		String str = "89451211512131";
		String str2 = "fd589213165131";
		String bin1 = hex2Bin(str);
		String bin2 = hex2Bin(str2);

		System.out.println(bin1.length() + "==" + bin2.length());
		System.out.println(bin2Hex(bin1));
		System.out.println(bin2Hex(bin2));
		String bin = xor(bin1,bin2);
		System.out.println(bin2Hex(bin));
	}

执行结果例如以下：

56==56
89451211512131
fd589213165131
741d8002477000

上述原理仍然是使用Integer.valueOf方法来实现的，仅仅只是是分段转换