请教，将resultset存入哪种机构中比较好？二维数组？arraylist?vector?有无原码借鉴下

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remanwang(玩玩儿) 帮忙啊

我先把结果组装好放进对象
在把对象放进arraylist

1.如果已知result长度，用array比较好。反之，如果结果空间不定，用vector比较合理。
2.Vector的内存开销比array要大得多。

贴个简单的吧 public class DocAttch
{

  protected Integer _ID ;
  protected Integer _DOCID ;
  protected String _FILENAME ;
  protected String _REALNAME ;
  public Integer get_ID()
  {
    return this._ID;
  }
  public void set_ID(Integer a_strID)
  {
    this._ID=a_strID;
  }
  public Integer get_DOCID()
  {
    return this._DOCID;
  }
  public void set_DOCID(Integer a_strDOCID)
  {
    this._DOCID=a_strDOCID;
  }
  public String get_FILENAME()
  {
    return this._FILENAME;
  }
  public void set_FILENAME(String a_strFILENAME)
  {
    this._FILENAME=a_strFILENAME;
  }
  public String get_REALNAME()
  {
    return this._REALNAME;
  }
  public void set_REALNAME(String a_strREALNAME)
  {
    this._REALNAME=a_strREALNAME;
  }
   /****************************************************************
    * 构造函数
    ****************************************************************/
   public DocAttch()
   {    this._ID= null;
    this._DOCID= null;
    this._FILENAME= null;
    this._REALNAME= null;
   }
}

public class DocAttchImpl extends DocAttch
{    public DocAttchImpl()
    {
    }    public void settxtid(String s)
    {
      Integer si;
      if(s != null)
      {
        si=new Integer(s);
        this.set_ID(si);
      }
    }
    public void settxtdocid(String s)
    {
      Integer si;
      if(s != null)
      {
        si=new Integer(s);
        this.set_DOCID(si);
      }
    }
    public void settxtfilename(String s)
    {
      if(s != null)
        this.set_FILENAME(s);
    }
    public void settxtrealname(String s)
    {
      if(s != null)
        this.set_REALNAME(s);
    }  public boolean Create() throws Exception
  {
      int i=0;
      java.sql.Connection myConn = null;
      java.sql.Statement st = null;      String strSql = "insert into [doc_attch]([DOCID],[FILENAME],[REALNAME]) values(";
      if(this.get_DOCID()!=null)  strSql=strSql + this.get_DOCID().toString()  + ",";
        else  strSql=strSql + "null" + ",";
      if(this.get_FILENAME()!=null)  strSql=strSql + "'" + this.ToSql(this.get_FILENAME()) + "'" + ",";
        else  strSql=strSql + "null" + ",";
      if(this.get_REALNAME()!=null)  strSql=strSql + "'" + this.ToSql(this.get_REALNAME()) + "'" + ")";
        else  strSql=strSql + "null" + ")";      try
      {
        myConn = DbConnectionManager.getConnection() ;
        st = myConn.createStatement() ;
        i=st.executeUpdate(strSql);
      }
      catch(Exception e)
      {
      }
      finally
      {
        if(st!=null)  st.close();
        if(myConn!=null)  myConn.close();
      }
      if(i>0){return true;}else{return false;}
  }
  public boolean Delete() throws Exception
  {
      java.sql.Connection myConn = null;
      java.sql.Statement st = null;
      int i=0;    String strSql = "delete from [doc_attch] where [id]="  + this.get_ID().toString() ;      cat.info(strSql);
      try
      {
        myConn = DbConnectionManager.getConnection() ;
        st = myConn.createStatement() ;
        i=st.executeUpdate(strSql);
      }
      catch(Exception e)
      {
        i=-1;
      }
      finally
      {
        if(st!=null)  st.close();
        if(myConn!=null)  myConn.close();
      }
      if(i>=0){return true;}else{return false;}
  }  public boolean Save() throws Exception
  {
      java.sql.Connection myConn = null;
      java.sql.Statement st = null;
      int i=0;      String strSql = "update [doc_attch] set ";
      strSql=strSql + "docid=";
      if(this.get_DOCID()!=null)  strSql=strSql + this.get_DOCID().toString()  + ",";
        else strSql=strSql + "null" + ",";
      strSql=strSql + "filename=";
      if(this.get_FILENAME()!=null)  strSql=strSql + "'" + this.ToSql(this.get_FILENAME()) + "'" + ",";
        else strSql=strSql + "null" + ",";
      strSql=strSql + "realname=";
      if(this.get_REALNAME()!=null)  strSql=strSql + "'" + this.ToSql(this.get_REALNAME()) + "'";
        else strSql=strSql + "null";
    strSql = strSql + " where [id]= "  + this.get_ID().toString() ;
      try
      {
        myConn = DbConnectionManager.getConnection() ;
        st = myConn.createStatement() ;
        i=st.executeUpdate(strSql);
      }
      catch(Exception e)
      {
      }
      finally
      {
        if(st!=null)  st.close();
        if(myConn!=null)  myConn.close();
      }
      if(i>0){return true;}else{return false;}
  }

public boolean Load(int a_intid) throws Exception
 {
 java.sql.Connection myConn = null;
 java.sql.Statement st = null;
 java.sql.ResultSet rs = null; int i=0;
 boolean flag=false;
 int itmp;
 double dtmp;
 String stmp;
 java.util.Date rtmp;

 String strSql = "select * from [doc_attch] where [id]=";
 strSql=strSql + Integer.toString(a_intid);
 try
 {
 myConn = DbConnectionManager.getConnection() ;
 st = myConn.createStatement();
 rs = st.executeQuery(strSql) ;
 if(rs.next())
 { itmp=rs.getInt("ID");
 if(!rs.wasNull()) this._ID=new Integer(rs.getInt("ID"));
 itmp=rs.getInt("DOCID");
 if(!rs.wasNull()) this._DOCID=new Integer(rs.getInt("DOCID"));
 stmp=rs.getString("FILENAME");
 if(!rs.wasNull()) this._FILENAME=theTrim(rs.getString("FILENAME"));
 stmp=rs.getString("REALNAME");
 if(!rs.wasNull()) this._REALNAME=theTrim(rs.getString("REALNAME"));
 flag=true;
 }
 }
 catch(Exception e)
 {
 }
 finally
 {
 rs=null;
 if(st!=null) st.close();
 if(myConn!=null) myConn.close();
 }
 return flag ;
 } public ArrayList LoadByPage(int PageNumber,int PageSize,String Condition) throws Exception
 {
 java.sql.Connection myConn = null;
 java.sql.Statement st = null;
 java.sql.ResultSet rs = null;
 ArrayList al=new ArrayList();
 int i;
 int itmp;
 double dtmp;
 String stmp;
 java.util.Date rtmp;

 String strSql = "select id,doc_no,script_no,title,createdate from [doc_attch] "; try
 {
 myConn = DbConnectionManager.getConnection() ;
 st = myConn.createStatement(1004,1007);
 if(!Condition.equals(""))
 {
 Condition=" where " + Condition;
 }

 rs = st.executeQuery(strSql + Condition) ;
 rs.absolute((PageNumber-1)*PageSize+1);
 i=0;
 while(i<PageSize && !rs.isAfterLast())
 {
 DocAttch fc=new DocAttch(); itmp=rs.getInt("ID");
 if(!rs.wasNull()) fc.set_ID(new Integer(rs.getInt("ID")));
 al.add(fc);
 rs.next();
 i++;
 }
 }
 catch(Exception e)
 {
 al=null;
 }
 finally
 {
 rs=null;
 if(st!=null) st.close();
 if(myConn!=null) myConn.close();
 }
 return al ;
 } public ArrayList LoadAll(String Condition) throws Exception
 {
 java.sql.Connection myConn = null;
 ArrayList al=new ArrayList();
 try
 {
 myConn = DbConnectionManager.getConnection() ;
 al=LoadAll(Condition,myConn);
 }
 catch(Exception e)
 {
 al=null;
 }
 finally
 {
 if(myConn!=null) myConn.close();
 }
 return al ;
 } public ArrayList LoadAll(String Condition,java.sql.Connection myConn) throws Exception
 {
 java.sql.Statement st = null;
 java.sql.ResultSet rs = null;
 ArrayList al=new ArrayList();
 int i;
 int itmp;
 double dtmp;
 String stmp;
 java.util.Date rtmp;

 String strSql = "select * from [doc_attch]"; try
 {
 st = myConn.createStatement(1004,1007);
 if(!Condition.equals(""))
 {
 Condition=" where " + Condition;
 }

 rs = st.executeQuery(strSql + Condition) ;
 i=0;
 while(!rs.isAfterLast())
 {
 DocAttch fc=new DocAttch(); itmp=rs.getInt("ID");
 if(!rs.wasNull()) fc.set_ID(new Integer(rs.getInt("ID")));
 itmp=rs.getInt("DOCID");
 if(!rs.wasNull()) fc.set_DOCID(new Integer(rs.getInt("DOCID")));
 stmp=rs.getString("FILENAME");
 if(!rs.wasNull()) fc.set_FILENAME(theTrim(rs.getString("FILENAME")));
 stmp=rs.getString("REALNAME");
 if(!rs.wasNull()) fc.set_REALNAME(theTrim(rs.getString("REALNAME")));
 al.add(fc);
 rs.next();
 }
 }
 catch(Exception e)
 {
 al=null;
 }
 finally
 {
 rs=null;
 if(st!=null) st.close();
 }
 return al ;
 } public ArrayList LoadAll(String a_strFieldName,int a_intFID) throws Exception
 {
 Integer itmp=new Integer(a_intFID);
 String strSql=a_strFieldName + "=" + itmp.toString();
 return LoadAll(strSql) ;
 }

 public int Count() throws Exception
 {
 java.sql.Connection myConn = null;
 java.sql.Statement st = null;
 java.sql.ResultSet rs = null;
 int fc=0; try
 {
 myConn = DbConnectionManager.getConnection() ;
 st = myConn.createStatement() ;
 rs = st.executeQuery("select count(*) as doc_attchCount from [doc_attch] ");
 if(rs.next())
 {
 fc=rs.getInt("doc_attchCount");
 }
 }
 catch(Exception e)
 {
 fc=-1;
 }
 finally
 {
 rs=null;
 if(st!=null) st.close();
 if(myConn!=null) myConn.close();
 }
 return fc ;
 } private String ToSql(String a_strSql)
 {
 return StringUtils.replace(a_strSql, "'", "''");
 }
 private String theTrim(String a_strSql)
 {
 return a_strSql.trim();
 }}

其实都可以，看你自己的习惯了。在我周围使用ArrayList得多一些。但是也是先组装成一个Vector实例，然后返回他的Enumeration.请看下面的一个ejbFind的例子：
//FilesBean.java
....
public Enumeration ejbFindByTitle(String title,int order) throws FinderException,RemoteException{
    //通用数据库连接
    PreparedStatement pstmt=null;
    Connection conn=null;
    DataSource ds = null;
    Vector v=new Vector();
    try{
//System.out.println("ejbFindByTitle("+title+")方法被调用。");
//System.out.println("begin to connect the database...");
/*
          * 获得数据库连接
          */
          Context ic = new InitialContext();
ds = (DataSource)ic.lookup("jdbc/webbos");
conn = ds.getConnection();
/*
* 在数据库中查找这个标题
*/
//System.out.println("begin scaning...");
if(order==EInclude.ORDERBYNULL)
pstmt=conn.prepareStatement("select fileID from file where title like ?");
if(order==EInclude.ORDERBYAUTHOR)//order by author
pstmt=conn.prepareStatement("select fileID from file where title like ? order by author");
if(order==EInclude.ORDERBYUPLOADDATE)//order by uploadDate;
pstmt=conn.prepareStatement("select fileID from file where title like ? order by uploadDate");
if(order==EInclude.ORDERBYSUBJECTID)//order by subjectID
pstmt=conn.prepareStatement("select fileID from file where title like ? order by subjectID");
pstmt.setString(1,"%"+title+"%");
//System.out.println("executing...");
ResultSet rs=pstmt.executeQuery();
//System.out.println("finish data scaning...");
/*
*插入每一个找到的主键到一个向量中
*/
while(rs.next()){
int fileID=rs.getInt("fileID");
v.addElement(new FilesPK(fileID));
}
/*
* 返回一个找到的主键的列举
*/
return v.elements();
    }
    catch(Exception e){
throw new FinderException(e.toString());
    }
    finally{
/*
* 为其他Bean释放数据库连接
*/
try{
if(pstmt!=null) pstmt.close();
}
catch(Exception e){}
try{
if(conn!=null) conn.close();
}
catch(Exception e){}
    }
}

看来你是要写BMP吧。我认为可以另外加一个表A和表B，A里面存放目前所有的表名，B记录每一表的字段类型，名称，是否可以空，主键等等。
然后对表结构修改的时候就对这两个表同时修改，保证这两个表记录的是当前你的表结构。
从数据库读写的时候，首先从这两个表来确定读什么字段，怎么读。

那就用变常数组Vector呗，要是不知道字段多少可以Vector 套Vector 呗。

/** 将查询数据库获得的结果集转化为二维数组返回 
 * 利用 ResultSetMetaData 获得结果集中的字段数目 k=ResultSetMetaData.getColumnCount(); 
 * 定义vector[k]; 将每个字段的结果集放入 vector[k]中。 
 * 定义二维数组String[k][v[0].size]; 将vector[k] copyinto 到相应的二维数组中 
 * 返回的二维数组为：String【i】【j】 i=字段数目; j=单个字段的记录条数 
 * @param rs ResultSet 作为参数 
 * @return 
 */
 public String[][] resultTwoArray(ResultSet rs)
 {
 try
 {
 ResultSetMetaData rsmd=rs.getMetaData();
 int k=rsmd.getColumnCount(); // 取出字段数目
System.out.println("字段返回类型＝|"+rsmd.getColumnTypeName(1)+"|");
 System.out.println("########查询字段数目k="+k);
 if(k<1)
 { String[][] nul=null;
 return nul;
 }
 Vector v[]=new Vector[k];
 for(int i=0;i<k;i++)
 v[i]=new Vector(); while(rs.next())
 { for(int i=0;i<k;i++)
 v[i].addElement(rs.getObject(i+1));
 } if(v[0]==null||v[0].size()==0)
 { String[][] nul2=null;
 return nul2;
 }
 String[][] arr=new String[k][v[0].size()];
 for(int p=0;p<k;p++)
 v[p].copyInto(arr[p]); // 将 Vector[p] copy 到数组 arr[p]中 //******************** null will be replaced with "" *************//
 for(int i=0;i<arr.length;i++)
 { for(int j=0;j<arr[0].length;j++)
 if(arr[i][j]==null)
 arr[i][j]="";
 }
 return arr;
 }
 catch(Exception e)
 { e.printStackTrace();
 }
 return null;
 }

tang1980(与同仁共勉之) 真不错哦，又快又省内存
我想用arraylist + string[col] 都不如你这个返回数组的好吧
对不起，java语法不太熟，那个vector 用不用在程序里释放掉？

vector就象数组差不多,
在java中,资源是会自动回收的,这些是不用客户担心的。IF YOU HAVE ANY QUESTION ,YOU CAN CONTACT ME WITH E-MAIL:[email protected]

调试易

请教，将resultset存入哪种机构中比较好？二维数组？arraylist?vector?有无原码借鉴下

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