shardingJdbc3.x 版本的分页bug问题解析

@Override
public SQLRouteResult route(final String logicSQL, final List<Object> parameters, final SQLStatement sqlStatement) {
    ......
    if (sqlStatement instanceof SelectStatement && null != ((SelectStatement) sqlStatement).getLimit()) {
        processLimit(parameters, (SelectStatement) sqlStatement);
    }
    ......
}
private void processLimit(final List<Object> parameters, final SelectStatement selectStatement) {
    boolean isNeedFetchAll = (!selectStatement.getGroupByItems().isEmpty() || !selectStatement.getAggregationSelectItems().isEmpty()) && !selectStatement.isSameGroupByAndOrderByItems();
    selectStatement.getLimit().processParameters(parameters, isNeedFetchAll, databaseType);
}

* @param parameters parameters
 * @param isFetchAll is fetch all data or not
 * @param databaseType database type
 */
public void processParameters(final List<Object> parameters, final boolean isFetchAll, final DatabaseType databaseType) {
    fill(parameters);
    rewrite(parameters, isFetchAll, databaseType);
}
private void fill(final List<Object> parameters) {
    int offset = 0;
    if (null != this.offset) {
        offset = -1 == this.offset.getIndex() ? getOffsetValue() : NumberUtil.roundHalfUp(parameters.get(this.offset.getIndex()));
        this.offset.setValue(offset);
    }
    int rowCount = 0;
    if (null != this.rowCount) {
        rowCount = -1 == this.rowCount.getIndex() ? getRowCountValue() : NumberUtil.roundHalfUp(parameters.get(this.rowCount.getIndex()));
        this.rowCount.setValue(rowCount);
    }
    if (offset < 0 || rowCount < 0) {
        throw new SQLParsingException("LIMIT offset and row count can not be a negative value.");
    }
}
private void rewrite(final List<Object> parameters, final boolean isFetchAll, final DatabaseType databaseType) {
    int rewriteOffset = 0;
    int rewriteRowCount;
    if (isFetchAll) {
        rewriteRowCount = Integer.MAX_VALUE;
    } else if (isNeedRewriteRowCount(databaseType)) {
        rewriteRowCount = null == rowCount ? -1 : getOffsetValue() + rowCount.getValue();
    } else {
        rewriteRowCount = rowCount.getValue();
    }
    if (null != offset && offset.getIndex() > -1) {
        parameters.set(offset.getIndex(), rewriteOffset);
    }
    if (null != rowCount && rowCount.getIndex() > -1) {
        parameters.set(rowCount.getIndex(), rewriteRowCount);
    }
}