private void refresh() {
		// maintain byte cache length which could be longer than length
		bytes = new byte[bytes.length];
		try {
			program.getMemory().getBytes(address, bytes);
			isValid = true;
		}
		catch (MemoryAccessException e) {
			throw new RuntimeException(
				"Not enough bytes in memory buffer to create code unit: " + e.getMessage());
		}
	}
Creates a pseudo code unit without a program.
@param addr the minimum address of this code unit.
@param length the length  of this code unit.
@param cacheLength the number of memBuffer bytes to be available within this CodeUnit MemBuffer
@param memBuffer the memory buffer where bytes can be obtained for this code unit.
@throws AddressOverflowException if code unit length causes wrap within space
Ghidra/Framework/SoftwareModeling/src/main/java/ghidra/app/util/PseudoCodeUnit.java