十进制转为二进制/八进制/十六进制_JAVA_编程开发_程序员俱乐部

class="java" name="code">
private static final char[] chs = { '0', '1', '2', '3', '4', '5', '6', '7',
			'8', '9', 'A', 'B', 'C', 'D', 'E', 'F' };

	public static String toHexString(int x) {
		return convert(x, 4);
	}

	public static String toOctalString(int x) {
		return convert(x, 3);
	}

	public static String toBinaryString(int x) {
		return convert(x, 1);
	}

	private static String convert(int x, int shift) {
		int mask = (1 << shift) - 1;
		char[] result = new char[32];
		int pos = 32;

		do {
			result[--pos] = chs[x & mask];
			x >>>= shift;
		} while (x != 0);

		// 起始偏移位置：pos表示当前索引位置
		// 偏移数：32-pos表示最后一位索引位置-当前索引位置+1,即总长度-当前索引位置
		return new String(result, pos, 32 - pos);
	}

		System.out.println(toBinaryString(-23423));
		System.out.println(Integer.toBinaryString(-23423));

		System.out.println(toOctalString(21321));
		System.out.println(Integer.toOctalString(21321));

		System.out.println(toHexString(21321));
		System.out.println(Integer.toHexString(21321));