/**
* 获取分页查询sql <功能详细描述> [参数说明]
*
* @return void [返回类型说明]
* @exception throws [异常类型] [异常说明]
* @see [类、类#方法、类#成员]
*/
public String queryPagedSql(Object obj, int pageIndex, int pageSize) {
String querySql = querySql(obj);
int offset = pageSize * (pageIndex - 1);
int limit = pageSize * pageIndex;
final boolean isSupportsVariableLimit = dialect.supportsVariableLimit(); // 是否支持物理分页
final boolean isSupportsLimit = dialect.supportsLimit(); // 是否支持limit
final boolean isSupportsLimitOffset = dialect.supportsLimitOffset(); // 是否支持offset
// 如果不支持物理分页，直接返回sql
if (!isSupportsVariableLimit || (!isSupportsLimit && !isSupportsLimitOffset)) {
return querySql;
} else {
// 如果支持
String limitSql = dialect.getLimitString(querySql, offset, limit);
return limitSql;
}
}
/**
* 获取查询条件的Setter对象 <功能详细描述>
*
* @param obj
* @return [参数说明]
* @return PreparedStatementSetter [返回类型说明]
* @exception throws [异常类型] [异常说明]
* @see [类、类#方法、类#成员]
*/
public PreparedStatementSetter getPagedQueryCondtionSetter(Object obj, int offset, int limit) {
final MetaObject metaObject = MetaObjectUtils.forObject(obj);
// 如果支持isSupportsLimitOffset并且当前需要偏移值
// final boolean isSupportsVariableLimit = dialect.supportsVariableLimit();//是否支持物理分页
final boolean isBindOnFirst = dialect.bindLimitParametersFirst(); // 是否绑定在前
final boolean isSupportsLimit = dialect.supportsLimit(); // 是否支持limit
final boolean isSupportsLimitOffset = dialect.supportsLimitOffset(); // 是否支持offset
final boolean bindLimitParametersInReverseOrder = dialect.bindLimitParametersInReverseOrder();
final boolean isNeedSetOffset =
isSupportsLimitOffset && (offset > 0 || dialect.forceLimitUsage());
final boolean isUseMaxForLimit = dialect.useMaxForLimit();
final int trueOffset = offset;
final int trueLimit = isUseMaxForLimit ? limit : limit - offset;
PreparedStatementSetter res =
new PreparedStatementSetter() {
@Override
public void setValues(PreparedStatement ps) throws SQLException {
int i = 1;
if (isBindOnFirst) {
if (bindLimitParametersInReverseOrder) {
if (isSupportsLimit) {
ps.setInt(i++, trueLimit);
}
if (isNeedSetOffset) {
ps.setInt(i++, trueOffset);
}
} else {
if (isNeedSetOffset) {
ps.setInt(i++, trueOffset);
}
if (isSupportsLimit) {
ps.setInt(i++, trueLimit);
}
}
}
for (Entry<String, String> entryTemp : queryConditionKey2SqlMapping.entrySet()) {
String queryKeyName = entryTemp.getKey();
Object valueObj = metaObject.getValue(queryKeyName);
if (ObjectUtils.isEmpty(valueObj)) {
continue;
}
JdbcType jdbcType = queryConditionKey2JdbcTypeMapping.get(queryKeyName);
JdbcUtils.setPreparedStatementValueForSimpleType(ps, i++, valueObj, jdbcType);
}
if (!isBindOnFirst) {
if (bindLimitParametersInReverseOrder) {
if (isSupportsLimit) {
ps.setInt(i++, trueLimit);
}
if (isNeedSetOffset) {
ps.setInt(i++, trueOffset);
}
} else {
if (isNeedSetOffset) {
ps.setInt(i++, trueOffset);
}
if (isSupportsLimit) {
ps.setInt(i++, trueLimit);
}
}
}
}
};
return res;
}
public boolean isMatch(Dialect dialect) {
return dialect.supportsLimit() && dialect.supportsLimitOffset();
}