dbpages.java

自己整理的一些java工具类包括文件处理

package cn.com.pubinfo.util;

import java.util.*;
import org.apache.torque.util.BasePeer;
import org.apache.torque.util.*;
/**
 * <p>Title: DBPages</p>
 * <p>Description: Peer==>DBPages==>listData==>PageInfo==>pageHTML</p>
 * <p>Copyright: Copyright (c) 2003</p>
 * <p>Company: pubinfo</p>
 * @author chineseren
 * @version 1.0
 */

public class DBPages {
  private String sql;
  private Criteria  crit;
  private int startIndex;
  private List list;
  private PageInfo pageInfo;
  public boolean isSql;

  //通过sql
  public DBPages(String sql,int startIndex) {
    this(sql,startIndex,AppSystem.PAGESIZE);
  }
  public DBPages(String sql,int startIndex,int pageSize) {
    Debug.debug("The SQL put in DBPages is: " + sql);
    this.sql = sql;
    this.startIndex  = startIndex;
    pageInfo = new PageInfo(startIndex);
    pageInfo.setPageSize(pageSize);
    this.isSql = true ;
  }

  //通过crit==>sql,其实fieldNames可以用'*'代替,可是king把'*'过滤了:(
  public DBPages(Criteria crit,List fieldNames,int startIndex) {
    this(crit,fieldNames,startIndex,AppSystem.PAGESIZE);
  }
  public DBPages(Criteria crit,List fieldNames,int startIndex,int pageSize) {
    this(crit,null,fieldNames,startIndex,pageSize);
  }
  //添加了orderby,比如:"col1 desc,col2 asc"
  public DBPages(Criteria crit,String orderby,List fieldNames,int startIndex,int pageSize) {
    this.crit = crit;
    this.startIndex  = startIndex;
    pageInfo = new PageInfo(startIndex);
    pageInfo.setPageSize(pageSize);
    this.isSql = true ;
    try{
      this.sql = BasePeer.createQueryString(crit);
      int pos1 = this.sql.indexOf("SELECT  FROM");
      if(pos1 !=-1){
        this.sql = this.sql.substring(pos1+12,this.sql.length());
        String tempStr = "";
        Iterator iterator = fieldNames.iterator();
        while(iterator.hasNext()){
          tempStr = tempStr+","+(String)iterator.next();
        }
         tempStr = tempStr.substring(1,tempStr.length());
         this.sql ="SELECT "+tempStr+" FROM"+ this.sql;
       }

       //添加order by语句
       if(null != orderby && !"".equals(orderby)){
         this.sql += " ORDER BY " + orderby;
       }

       Debug.debug("The SQL BasePeer.createQueryString(crit) is: " + this.sql);
    }catch(Exception ex){
      Debug.error("BasePeer.createQueryString(crit) ERROR in DBPages!",ex);
    }
  }

  public List getPage(){
    String s=null;
    String strSQL = null;
    String strCount = null;
    String strOrder = null;
    List ls = null;
    String colStr = "";
    String tableStr = "";
    String whereStr = "";
    com.workingdogs.village.Record tc = null;
    Debug.println(this.sql);
    try{
    if(isSql==true){//是普通的sql语句
      this.sql = this.sql.trim();
      String tempSql = this.sql.toUpperCase();
      int a = this.sql.indexOf("*");
      if(a !=-1 ){
        throw new Exception("error sql!" );
      }
      int colpos = tempSql.indexOf(" FROM ");
      a = tempSql.indexOf("WHERE");
      if(a != -1){//有where
        tableStr =this.sql.substring(colpos+6,a);
        whereStr =  this.sql.substring(a,tempSql.length());
      }else{//没有where
        tableStr =this.sql.substring(colpos+5,tempSql.length());
        int j=tableStr.toUpperCase().indexOf(" ORDER ");
        if(j != -1){//说明有order by
          tableStr = tableStr.substring(0,j);
        }
        whereStr = "";
      }
      int k=whereStr.toUpperCase().indexOf(" ORDER ");
      if(k!= -1){//有order by语句
          whereStr=whereStr.substring(0,k);
      }

    Debug.println(tableStr);
    Debug.println(whereStr);
      strCount = "select count(*) as C from " + tableStr + whereStr;

    }else{//是torque语句

    }
    }catch(Exception ex){
      Debug.error("DBPages.getPage() generate SQL ERROR!",ex);
      return null;
    }

    //取得分页记录集
    try{
      Debug.println(strCount);
      ls = BasePeer.executeQuery(strCount);
      tc = (com.workingdogs.village.Record )ls.get(0);
      pageInfo.setTotalRecord(tc.getValue("C").asInt());//所有记录数
      Debug.debug("DBPages.getPage() list size is:" + pageInfo.getTotalRecords());
    }catch(Exception exx){
      Debug.error("DBPages.getPage() get count of row from db ERROR!",exx) ;
      return null;
    }
    try{
      list = BasePeer.executeQuery(this.sql, this.startIndex - 1,
          pageInfo.getPageSize(), org.apache.torque.Torque.getDefaultDB(), false);
    }catch(Exception ex){
      Debug.error("DBPages.getPage() to get paging record from db ERROR!",ex);
      Debug.debug("DBPages.getPage() strSQL is: " + strSQL) ;
      return null;
    }
    return list;
  }

  public PageInfo getPageInfo() {
    return this.pageInfo;
  }
}