package com.joe.utilities.core.jdbc.jdbc.jdbcTemplate;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.ArrayList;
import java.util.List;
import org.springframework.dao.DataAccessException;
import org.springframework.jdbc.core.ResultSetExtractor;
import org.springframework.jdbc.core.RowMapper;
import org.springframework.util.Assert;
public class SplitPageResultSetExtractor implements ResultSetExtractor {
private final int start;// 起始行号
private final int len;// 结果集合的长度
private final RowMapper rowMapper;// 行包装器
public SplitPageResultSetExtractor(RowMapper rowMapper, int start, int len) {
Assert.notNull(rowMapper, "RowMapper is required");
this.rowMapper = rowMapper;
this.start = start;
this.len = len;
}
/**
* 处理结果集合,被接口自动调用,该类外边不应该调用
*/
public Object extractData(ResultSet rs) throws SQLException,
DataAccessException {
List result = new ArrayList();
int rowNum = 0;
int end = start + len;
point: while (rs.next()) {
++rowNum;
if (rowNum < start) {
continue point;
} else if (rowNum >= end) {
break point;
} else {
result.add(this.rowMapper.mapRow(rs, rowNum));
}
}
return result;
}
}