MyBatis MapperProvider MessageFormat拼接批量SQL語句執行報錯的原因分析及解決辦法

最近在項目中有這麼一段代碼：下載服務器基礎業務數據進行本地批量插入操作，因項目中使用mybatis進行持久化操作，故直接考慮使用mybatis的批量插入功能。

1.以下是Mapper接口的部分代碼

public interface PrintMapper
{
@InsertProvider(type = PrintMapperProvider.class,method = "insertAllLotWithVehicleCode4H2") void insertAllLotWithVehicleCode(List<LotWithVehicleCodeBO> lotWithVehicleCodes);
}

2.對應MapperProvider中函數片段

public String insertAllLotWithVehicleCode4H2(Map<String,List<LotWithVehicleCodeBO>> map)
{
List<LotWithVehicleCodeBO> lotWithVehicleCodeBOs = map.get("list");

StringBuilder sb = new StringBuilder("INSERT INTO MTC_LOT_WITH_VEHICLE_CODE (LOT_CODE,PRODUCT_VEHICLE_CODE) VALUES ");

MessageFormat messageFormat = new MessageFormat("(" +
"#'{'list[{0}].lotCode }," +
"#'{'list[{0}].productVehicleCode }" +
")"); int size = lotWithVehicleCodeBOs.size(); for (int i = 0; i < size; i++)
{
sb.append(messageFormat.format(new Object[]{i})); 
if (i < size - 1) sb.append(",");
} 
return sb.toString();
}

3.service層

@Transactionalpublic void synchLotWithVehicleCodeToLocalDB(List<LotWithVehicleCodeBO> lotWithVehicleCodeBOs)
{ if(null != lotWithVehicleCodeBOs && lotWithVehicleCodeBOs.size()>0)
{
printMapper.insertAllLotWithVehicleCode(lotWithVehicleCodeBOs);
}
}

程序上線的時候沒有發生問題，在業務量猛增的時候，大約同時執行500條以上的時候程序就開始報錯：

Caused by: org.apache.ibatis.builder.BuilderException: Improper inline parameter map format. Should be: #{propName,attr1=val1,attr2=val2}
at org.apache.ibatis.builder.SqlSourceBuilder$ParameterMappingTokenHandler.buildParameterMapping(SqlSourceBuilder.java:89)
at org.apache.ibatis.builder.SqlSourceBuilder$ParameterMappingTokenHandler.handleToken(SqlSourceBuilder.java:43)
at org.apache.ibatis.parsing.GenericTokenParser.parse(GenericTokenParser.java:25)
at org.apache.ibatis.builder.SqlSourceBuilder.parse(SqlSourceBuilder.java:24)
at org.apache.ibatis.builder.annotation.ProviderSqlSource.createSqlSource(ProviderSqlSource.java:57)
... 61 more

異常已指明SQL語句構建問題，DEBUG進去：

問題根源：

MessageFormat messageFormat = new MessageFormat("(" +
"#'{'list[{0}].lotCode }," +
"#'{'list[{0}].productVehicleCode }," +
")");
int size = lotWithVehicleCodeBOs.size();
for (int i = 0; i < size; i++)
{
　　 sb.append(messageFormat.format(new Object[]{i})); 
　　if (i<size-1) sb.append(",");
}

當size達到3位數以上時構建出的message為：

(#{list[1,000].lotCode },#{list[1,000].productVehicleCode })

解決辦法：messageFormat.format(new Object[]{i+""}