java - 在数据表中自动添加行 ID (jQuery)

Question

这是给出的 PHP 代码

   <?php

    $aColumns = array( 'engine', 'browser', 'platform', 'version', 'grade' );

    $sTable = "ajax";
    $gaSql['user']       = "";
    $gaSql['password']   = "";
    $gaSql['db']         = "";
    $gaSql['server']     = "localhost";

    include( $_SERVER['DOCUMENT_ROOT']."/datatables/mysql.php" );   
    $gaSql['link'] =  mysql_pconnect( $gaSql['server'], $gaSql['user'], $gaSql['password']  ) or
        die( 'Could not open connection to server' );

    mysql_select_db( $gaSql['db'], $gaSql['link'] ) or 
        die( 'Could not select database '. $gaSql['db'] );

    $sLimit = "";
    if ( isset( $_GET['iDisplayStart'] ) && $_GET['iDisplayLength'] != '-1' )
    {
        $sLimit = "LIMIT ".mysql_real_escape_string( $_GET['iDisplayStart'] ).", ".
            mysql_real_escape_string( $_GET['iDisplayLength'] );
    }

    $sOrder = "";
    if ( isset( $_GET['iSortCol_0'] ) )
    {
        $sOrder = "ORDER BY  ";
        for ( $i=0 ; $i<intval( $_GET['iSortingCols'] ) ; $i++ )
        {
            if ( $_GET[ 'bSortable_'.intval($_GET['iSortCol_'.$i]) ] == "true" )
            {
                $sOrder .= $aColumns[ intval( $_GET['iSortCol_'.$i] ) ]."
                    ".mysql_real_escape_string( $_GET['sSortDir_'.$i] ) .", ";
            }
        }

        $sOrder = substr_replace( $sOrder, "", -2 );
        if ( $sOrder == "ORDER BY" )
        {
            $sOrder = "";
        }
    }

    $sWhere = "";
    if ( isset($_GET['sSearch']) && $_GET['sSearch'] != "" )
    {
        $sWhere = "WHERE (";
        for ( $i=0 ; $i<count($aColumns) ; $i++ )
        {
            $sWhere .= $aColumns[$i]." LIKE '%".mysql_real_escape_string( $_GET['sSearch'] )."%' OR ";
        }
        $sWhere = substr_replace( $sWhere, "", -3 );
        $sWhere .= ')';
    }

    /* Individual column filtering */
    for ( $i=0 ; $i<count($aColumns) ; $i++ )
    {
        if ( isset($_GET['bSearchable_'.$i]) && $_GET['bSearchable_'.$i] == "true" && $_GET['sSearch_'.$i] != '' )
        {
            if ( $sWhere == "" )
            {
                $sWhere = "WHERE ";
            }
            else
            {
                $sWhere .= " AND ";
            }
            $sWhere .= $aColumns[$i]." LIKE '%".mysql_real_escape_string($_GET['sSearch_'.$i])."%' ";
        }
    }
    $sQuery = "
        SELECT SQL_CALC_FOUND_ROWS id, ".str_replace(" , ", " ", implode(", ", $aColumns))."
        FROM   $sTable
        $sWhere
        $sOrder
        $sLimit
    ";
    $rResult = mysql_query( $sQuery, $gaSql['link'] ) or die(mysql_error());

    $sQuery = "
        SELECT FOUND_ROWS()
    ";
    $rResultFilterTotal = mysql_query( $sQuery, $gaSql['link'] ) or die(mysql_error());
    $aResultFilterTotal = mysql_fetch_array($rResultFilterTotal);
    $iFilteredTotal = $aResultFilterTotal[0];

    /* Total data set length */
    $sQuery = "
        SELECT COUNT(".$sIndexColumn.")
        FROM   $sTable
    ";
    $rResultTotal = mysql_query( $sQuery, $gaSql['link'] ) or die(mysql_error());
    $aResultTotal = mysql_fetch_array($rResultTotal);
    $iTotal = $aResultTotal[0];

    $output = array(
        "sEcho" => intval($_GET['sEcho']),
        "iTotalRecords" => $iTotal,
        "iTotalDisplayRecords" => $iFilteredTotal,
        "aaData" => array()
    );

    while ( $aRow = mysql_fetch_array( $rResult ) )
    {
        $row = array();

        // Add the row ID and class to the object
        $row['DT_RowId'] = 'row_'.$aRow['id'];
        $row['DT_RowClass'] = 'grade'.$aRow['grade'];

        for ( $i=0 ; $i<count($aColumns) ; $i++ )
        {
            if ( $aColumns[$i] == "version" )
            {
                $row[] = ($aRow[ $aColumns[$i] ]=="0") ? '-' : $aRow[ $aColumns[$i] ];
            }
            else if ( $aColumns[$i] != ' ' )
            {
                $row[] = $aRow[ $aColumns[$i] ];
            }
        }
        $output['aaData'][] = $row;
    }

    echo json_encode( $output );
?>

我需要用java开发一个程序，就像PHP代码一样(我无法理解PHP代码)，这是我的java代码(部分)。

public class DTSerializedObject implements java.io.Serializable
    {
        public int iTotalRecords;
        public int iTotalDisplayRecords;
        public ArrayList<Object> aaData;
    }

函数内部

    ArrayList<Object> jsonarray = new ArrayList<Object>();
    DTSerializedObject dts = new DTSerializedObject();
dts.iTotalRecords = dts.iTotalDisplayRecords = 30;
                String category=null;
                while(rs.next())
                {
                    category="Normal";
                    ArrayList<Object> ja = new ArrayList<Object>();
                    int topicno=rs.getInt("topicno");
                    ja.add(topicno);
                    ja.add(rs.getString("filename"));
                    ja.add(rs.getString("letterno"));
                    ja.add(rs.getString("date"));
                    if((rs.getString("category")).equals("2"))
                        category="Urgent";
                    ja.add("<center>"+category+"</center>");
                    ja.add(rs.getString("office"));
                    ja.add(rs.getString("subject")+"....");
                    ja.add("<center><a class='anc' href=\"/Spandana2/specifiedTopicDetailsAndReplies.do?topicno="+topicno+"&purpose=view&jsessionid="+java.util.UUID.randomUUID().toString().replace("-","").toUpperCase()+"\">View</a></center>");
                    jsonarray.add(ja);
                }
                dts.aaData = jsonarray;

如何将 DT_RowId、DT_RowClass 选项添加到我的 java 代码中。上述 PHP 代码的预期 JSON 输出格式是什么？

提前致谢

Answer 1

像这样创建一个对象

class Bean{
      public String col1;
      public String col2;
      public String DT_RowClass;
}

在从数据库获取数据时，创建了一个对象(Bean)并将值分配给每一行的该对象属性。

ArrayList al = new ArrayList();    
while(rs.next){
         Bean b = new Bean();
         b.col1(rs.getString(1));
         b.col2(rs.getString(2));
         if(rs.getString(3))
              b.DT_RowClass = "class1";
         else
              b.DT_RowClass = "class2";
         al.add(b);
    }

创建了一个类，表示在网页中显示数据所需的 json 格式。创建该类的对象 (obj) 并将适当的值分配给 iTotalRecords & iTotalDisplayRecords & aaData = al;

public class DTSerializedObject implements java.io.Serializable
    {
        public int iTotalRecords;
        public int iTotalDisplayRecords;
        public ArrayList<Object> aaData;
    }

最后使用 flexjson 序列化该对象.

 String result = new flexjson.JSONSerializer().exclude("class").serialize(obj);
    response.setContentType("application/json");
    response.setHeader("Cache-Control", "no-store");
    response.getWriter().print(result);