spring4 -- 基于jdbcTemplate的分页

项目中的通用分页组主要是分页类，下面的分页类是对网上常见的一个类的稍稍改造，针对的库是mysql，所以分页语句就比较简单，使用了limit关键字：

public class Page{ //一页显示的记录数 private int numPerPage; //记录总数 private int totalRows; //总页数 private int totalPages; //当前页码 private int currentPage; //起始行数 private int startIndex; //结束行数 private int lastIndex; //结果集存放List private List<Map<String, Object>> resultList; /**分页构造函数 * @param sql 包含筛选条件的sql，但不包含分页相关约束，如mysql的limit * @param currentPage 当前页 * @param numPerPage 每页记录数 * @param jTemplate JdbcTemplate实例 */ public Page(String sql,int currentPage,int numPerPage,JdbcTemplate jTemplate){ if(jTemplate == null){ throw new IllegalArgumentException("Page.jTemplate is null"); }else if(sql == null || sql.equals("")){ throw new IllegalArgumentException("Page.sql is empty"); } //设置每页显示记录数 setNumPerPage(numPerPage); //设置要显示的页数 setCurrentPage(currentPage); //计算总记录数 StringBuffer totalSQL = new StringBuffer(" SELECT count(*) FROM ( "); totalSQL.append(sql); totalSQL.append(" ) totalTable "); //总记录数 setTotalRows(jTemplate.queryForInt(totalSQL.toString())); //计算总页数 setTotalPages(); //计算起始行数 setStartIndex(); //计算结束行数 setLastIndex(); System.out.println("lastIndex="+lastIndex); //使用mysql时直接使用limits StringBuffer paginationSQL = new StringBuffer(); paginationSQL.append(sql); paginationSQL.append(" limit " + startIndex + "," + lastIndex); //装入结果集 setResultList(jTemplate.queryForList(paginationSQL.toString())); } public int getCurrentPage() { return currentPage; } public void setCurrentPage(int currentPage) { this.currentPage = currentPage; } public int getNumPerPage() { return numPerPage; } public void setNumPerPage(int numPerPage) { this.numPerPage = numPerPage; } public List<Map<String, Object>> getResultList() { return resultList; } public void setResultList(List<Map<String, Object>> resultList) { this.resultList = resultList; } public int getTotalPages() { return totalPages; } //计算总页数 public void setTotalPages() { if(totalRows % numPerPage == 0){ this.totalPages = totalRows / numPerPage; }else{ this.totalPages = (totalRows / numPerPage) + 1; } } public int getTotalRows() { return totalRows; } public void setTotalRows(int totalRows) { this.totalRows = totalRows; } public int getStartIndex() { return startIndex; } public void setStartIndex() { this.startIndex = (currentPage - 1) * numPerPage; } public int getLastIndex() { return lastIndex; } //计算结束时候的索引 public void setLastIndex() { System.out.println("totalRows="+totalRows);/////////// System.out.println("numPerPage="+numPerPage);/////////// if( totalRows < numPerPage){ this.lastIndex = totalRows; }else if((totalRows % numPerPage == 0) || (totalRows % numPerPage != 0 && currentPage < totalPages)){ this.lastIndex = currentPage * numPerPage; }else if(totalRows % numPerPage != 0 && currentPage == totalPages){//最后一页 this.lastIndex = totalRows ; } } }

dao层：

/** * 查询包含所有字段的分页数据 * @param tableName * @param where * @return */ public List<Map<String, Object>> getPageListAllCol(String tableName,String where,int currentPage,int numPerPage){ String sql = "select * from " + tableName + where; Page page = new Page(sql, currentPage, numPerPage, sjc); return page.getResultList(); }

部分数据结果：

totalRows=60 numPerPage=15 lastIndex=15

其中分页类中用到的数据源，是由dao层作为参数传递进去的，dao层的数据源使用@autowared自动注入，具体注入可参考前面内容