java convert long to 64 bits(0|1) string

Bits.java

public class Bits{

	public static void main(String[] args){
		long val = -12435L;
		System.out.println(longBits(val));
		// 1111111111111111111111111111111111111111111111111100111101101101
		System.out.println(longBitsSpaced(val));
		// 11111111 11111111 11111111 11111111 11111111 11111111 11001111 01101101
	}
	
	public static String longBits(long val) {
		StringBuffer b = new StringBuffer(64);// 64 bits
		for(int i=63;i>=0; i--) {
			b.append((val & (1L<<i)) == 0 ? '0':'1');
		}
		return b.toString();
	}

	public static String longBitsSpaced(long val) {
		StringBuffer b = new StringBuffer(71);// 64 bits + 7 spaces
		for(int i=63;i>=0; i--) {
			b.append((val & (1L<<i)) == 0 ? '0':'1');
			if(i>0 && i%8 ==0) b.append(' ');
		}
		return b.toString();
	}
}