@Override
	public int getLength() {
		lock.acquire();
		try {
			checkIsValid();
			if (structLength == 0) {
				return 1; // positive length required
			}
			return structLength;
		}
		finally {
			lock.release();
		}
	}
Create cloned structure for target data type manager preserving source archive information.
<p>
WARNING! cloning non-packed structures which contain bitfields can produce invalid results
when switching endianness due to the differences in packing order.

@param dtm target data type manager
@return cloned structure
Ghidra/Framework/SoftwareModeling/src/main/java/ghidra/program/database/data/StructureDB.java