public Builder setSource(com.alipay.sofa.jraft.entity.LocalFileMetaOutter.FileSource value) {
                if (value == null) {
                    throw new NullPointerException();
                }
                bitField0_ |= 0x00000002;
                source_ = value.getNumber();
                onChanged();
                return this;
            }
<code>optional .jraft.FileSource source = 2;</code>
jraft-core/src/main/java/com/alipay/sofa/jraft/entity/LocalFileMetaOutter.java