/**
*
*
* <pre>
* 查询总数
* </pre>
*
* @author jundong.xu_C
* @param page
* @param parameterObject
* @param mappedStatement
* @param connection
* @throws SQLException
*/
protected void queryTotalRecord(
Page<?> page, Object parameterObject, MappedStatement mappedStatement, Connection connection)
throws SQLException {
BoundSql boundSql = mappedStatement.getBoundSql(parameterObject);
String sql = boundSql.getSql();
String countSql = this.buildCountSql(sql);
if (log.isDebugEnabled()) {
log.debug("分页时, 生成countSql: " + countSql);
}
List<ParameterMapping> parameterMappings = boundSql.getParameterMappings();
BoundSql countBoundSql =
new BoundSql(
mappedStatement.getConfiguration(), countSql, parameterMappings, parameterObject);
ParameterHandler parameterHandler =
new DefaultParameterHandler(mappedStatement, parameterObject, countBoundSql);
PreparedStatement pstmt = null;
ResultSet rs = null;
try {
pstmt = connection.prepareStatement(countSql);
parameterHandler.setParameters(pstmt);
rs = pstmt.executeQuery();
if (rs.next()) {
long totalRecord = rs.getLong(1);
int pageSize = page.getPageSize();
int totalPage = (int) (totalRecord + pageSize - 1) / pageSize;
page.setTotalSize(totalRecord);
page.setTotalPage(totalPage);
}
} finally {
if (rs != null)
try {
rs.close();
} catch (Exception e) {
if (log.isWarnEnabled()) {
log.warn("关闭ResultSet时异常.", e);
}
}
if (pstmt != null)
try {
pstmt.close();
} catch (Exception e) {
if (log.isWarnEnabled()) {
log.warn("关闭PreparedStatement时异常.", e);
}
}
}
}
/**
* 对SQL参数(?)设值
*
* @param ps
* @param mappedStatement
* @param boundSql
* @param parameterObject
* @throws SQLException
*/
private void setParameters(
PreparedStatement ps, MappedStatement mappedStatement, BoundSql boundSql)
throws SQLException {
ParameterHandler parameterHandler =
mappedStatement
.getConfiguration()
.newParameterHandler(mappedStatement, boundSql.getParameterObject(), boundSql);
parameterHandler.setParameters(ps);
}
/**
* 获取总计录
*
* @param parameterHandler
* @param connection
* @param countSql
* @return
* @throws Exception
*/
private int getTotal(ParameterHandler parameterHandler, Connection connection, String countSql)
throws Exception {
// MetaObject metaStatementHandler =
// MetaObject.forObject(parameterHandler);
// Object parameterObject =
// metaStatementHandler.getValue("parameterObject");
// TODO 缓存具有相同SQL语句和参数的总数
PreparedStatement prepareStatement = connection.prepareStatement(countSql);
parameterHandler.setParameters(prepareStatement);
ResultSet rs = prepareStatement.executeQuery();
int count = 0;
if (rs.next()) {
count = rs.getInt(1);
}
rs.close();
prepareStatement.close();
return count;
}
/**
* 获取总记录数
*
* @param sql 原始sql语句
* @param conn
* @param ms
* @param boundSql
* @return
* @throws SQLException
*/
private int getTotalCount(String sql, Connection conn, MappedStatement ms, BoundSql boundSql)
throws SQLException {
int start = sql.indexOf("from");
if (start == -1) {
throw new RuntimeException("statement has no 'from' keyword");
}
int stop = sql.indexOf("order by");
if (stop == -1) {
stop = sql.length();
}
String countSql = "select count(0) " + sql.substring(start, stop);
BoundSql countBoundSql =
new BoundSql(
ms.getConfiguration(),
countSql,
boundSql.getParameterMappings(),
boundSql.getParameterObject());
ParameterHandler parameterHandler =
new DefaultParameterHandler(ms, boundSql.getParameterObject(), countBoundSql);
PreparedStatement stmt = null;
ResultSet rs = null;
int count = 0;
try {
stmt = conn.prepareStatement(countSql);
// 通过parameterHandler给PreparedStatement对象设置参数
parameterHandler.setParameters(stmt);
rs = stmt.executeQuery();
if (rs.next()) {
count = rs.getInt(1);
}
} finally {
CloseableUtil.closeQuietly(rs);
CloseableUtil.closeQuietly(stmt);
}
return count;
}