Java 悲观锁 synchronized （member）{代码块}
Java 如果遇到会出现高并发的情况，一般建议使用悲观锁 ：synchronized （member）{代码块} 需要对数据库进行修改或新增的时候，建议写上事务–@Transactional
@Transactional
public Map<String, Object> saveCode(Member member, SessionRecord sr) {
// TODO Auto-generated method stub
log.getLogger(“dbeleven2020_s”).info(“saveCode-response params1:({}),params2:({})”, member, sr);
Map<String, Object> resp = new HashMap<String, Object>();
Map<String, Object> codeMap = new HashMap<String, Object>();
synchronized (member) {
codeMap.put(“accountId”, member.getAccountId());
// 这里要判断一下，该会员，是否有过sharecode
String hasCode = “”;
String code = “”;
hasCode = doubleEleven2020Mapper.selectIsHadCode(codeMap);
if (StringUtils.isEmpty(hasCode)) {
code = shareCodeService.generateShareCode(16);
codeMap.put(“shareCode”, code);
if (doubleEleven2020Mapper.addCode(codeMap) == 1) {
log.getLogger(“dbeleven2020_s”).info(“addCode-response params1:({}),params2:({})”, codeMap, true);
resp.put(“shareCode”, code);
}
}
else {
resp.put(“shareCode”, hasCode);
}
resp.put(“status”, true);
}
return resp;
}