private boolean checkInstruction(final Instruction instruction) {
        if (instruction == null) {
            LOG.warn("Null instructions element.");
            return false;
        }
        if (instruction.getRegion() == null) {
            LOG.warn("Null region with instruction: {}.", instruction);
            return false;
        }
        return true;
    }
Processing the instructions from the placement driver server.

@author jiachun.fjc
jraft-rheakv/rheakv-core/src/main/java/com/alipay/sofa/jraft/rhea/client/pd/InstructionProcessor.java