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用Spring的JdbcTemplate實現分頁功能

     public class Pagination extends JdbcDaoSupport{
  public static final int NUMBERS_PER_PAGE = 10;

  //一頁顯示的記錄數
  private int numPerPage;

  //記錄總數
  private int totalRows;

  //總頁數
     private int totalPages;

  //當前頁碼
  private int currentPage;

  //起始行數
  private int startIndex;

  //結束行數
  private int lastIndex;

  //結果集存放List

  private List resultList;

  //JdbcTemplate jTemplate

  private JdbcTemplate jTemplate;

  /**
  * 每頁顯示10條記錄的建構函式,使用該函式必須先給Pagination設定             currentPage,jTemplate初值
  * @param sql oracle語句
  */

  public Pagination(String sql){

  if(jTemplate == null){
   throw new IllegalArgumentException("com.deity.ranking.util.Pagination.jTemplate is null,please initial it first. ");

  }else if(sql.equals("")){

  throw new IllegalArgumentException("com.deity.ranking.util.Pagination.sql is empty,please initial it first. ");

  }
  new Pagination(sql,currentPage,NUMBERS_PER_PAGE,jTemplate);
  }

  /**分頁建構函式
  * @param sql 根據傳入的sql語句得到一些基本分頁資訊
  * @param currentPage 當前頁
  * @param numPerPage 每頁記錄數
  * @param jTemplate JdbcTemplate例項
  */

  public Pagination(String sql,int currentPage,int numPerPage,JdbcTemplate jTemplate){

  if(jTemplate == null){

  throw new IllegalArgumentException("com.deity.ranking.util.Pagination.jTemplate is null,please initial it first. ");

  }else if(sql == null || sql.equals("")){

  throw new IllegalArgumentException("com.deity.ranking.util.Pagination.sql is empty,please initial it first. ");

  }

  //設定每頁顯示記錄數
  setNumPerPage(numPerPage);

  //設定要顯示的頁數
  setCurrentPage(currentPage);

  //計算總記錄數
  StringBuffer totalSQL = new StringBuffer(" SELECT count(*) FROM ( ");

  totalSQL.append(sql);
  totalSQL.append(" ) totalTable ");

  //給JdbcTemplate賦值
  setJdbcTemplate(jTemplate);

  //總記錄數
  setTotalRows(getJdbcTemplate().queryForInt(totalSQL.toString()));

  //計算總頁數
  setTotalPages();

  //計算起始行數
  setStartIndex();

  //計算結束行數
  setLastIndex();

  System.out.println("lastIndex="+lastIndex);//////////////////
  //構造oracle資料庫的分頁語句

  StringBuffer paginationSQL = new StringBuffer(" SELECT * FROM( ");
  paginationSQL.append(" SELECT temp.* ,ROWNUM num FROM ( ");
  paginationSQL.append(sql);
  paginationSQL.append(") temp where ROWNUM <= " + lastIndex);

  paginationSQL.append(" ) WHERE

  num > " + startIndex);

  //裝入結果集
  setResultList(getJdbcTemplate().queryForList(paginationSQL.toString()));

  }

  /**
  * @param args
  */

  public static void main(String[] args) {
  // TODO Auto-generated method stub
  }

  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 getResultList() {
       return resultList;
  }

  public void setResultList(List resultList) {
       this.resultList = resultList;
  }

  public int getTotalPages() {
        return totalPages;
  }

  //計算總頁數

  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;
  }

  public JdbcTemplate getJTemplate() {
       return jTemplate;
  }

  public void setJTemplate(JdbcTemplate template) {
        jTemplate = template;
  }

  //計算結束時候的索引

  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){//最後一頁

  this.lastIndex = totalRows ;

  }

  }}在我的業務邏輯程式碼中:

  /**

  * find season ranking list from DC
  * @param areaId 選手區域id
  * @param rankDate 賽季
  * @param category 類別
  * @param characterName 角色名
  * @return List
  */

  public List findSeasonRankingList(Long areaId, int rankYear,int rankMonth,Long categoryId,String characterName) {

  //SQL語句
  StringBuffer sql = new StringBuffer(" SELECT C.USERID userid,D.POSNAME posname,C.GAMEID gameid,C.AMOUNT amount,C.RANK rank FROM ");
  //表
  sql.append(" (SELECT B.USERID USERID,");
  sql.append(" B.POSID POSID,");
  sql.append(" A.DISTRICT_CODE DISTRICTCODE,");
  sql.append(" A.GAMEID GAMEID,");
  sql.append(" AMOUNT AMOUNT,");
  sql.append(" RANK RANK ");
  sql.append(" FROM TB_FS_RANK A ");
  sql.append(" LEFT JOIN TB_CHARACTER_INFO B ");
  sql.append(" ON A.DISTRICT_CODE = B.DISTRICT_CODE ");
  sql.append(" AND A.GAMEID = B.GAMEID ");

  //附加條件
  if(areaId != null && areaId.intValue() != 0){
  sql.append(" and A.DISTRICT_CODE = " + areaId.intValue());
  }