private long parseString(String addr) throws NumberFormatException, AddressFormatException {
		if (addr.startsWith("0x") || addr.startsWith("0X")) {
			addr = addr.substring(2);
		}

		long mod = 0;
		if (unitSize > 1) {
			int ix = addr.indexOf('.');
			if (ix > 0) {
				String unitOffset = addr.substring(ix + 1);
				BigInteger bi = new BigInteger(unitOffset, 16);
				mod = bi.longValue();
				if (bi.bitLength() > 8 || mod >= unitSize) {
					throw new AddressFormatException("invalid address unit offset: ." + unitOffset);
				}
				addr = addr.substring(0, ix);
			}
		}

		BigInteger bi = new BigInteger(addr, 16);
		if (bi.bitLength() > 64) {
			throw new AddressFormatException("unsupported address offset: " + addr);
		}
		return (unitSize * bi.longValue()) + mod;
	}
Returns the unique id value for this space.
Ghidra/Framework/SoftwareModeling/src/main/java/ghidra/program/model/address/AbstractAddressSpace.java