JDBC从数据库中取值

你通过jdbc创建表都行，那就通过jdbc来读取呗，select * from mytable;用list来封装，ResultSetMetaData得到表的字段。setListResult(new ArrayList<Map>());
try {
    conn = getConnection();
    try {
        pstmt = conn.prepareStatement(sql);
    } catch (SQLException se) {
        throw new Exception("...");
    }
    Iterator inputParamsIte = params.iterator();
    int index = 1;
    try {
        while (inputParamsIte.hasNext()) {
            pstmt.setObject(index, inputParamsIte.next());
            index++;
        }
    } catch (SQLException se) {
        throw new Exception("...");
    }    try {
        rs = pstmt.executeQuery();
        ResultSetMetaData rsmd = rs.getMetaData();
        while (rs.next()) {
            Map map = new HashMap();
            for (int i = 1; i <= rsmd.getColumnCount(); i++) {
                if (rsmd.getColumnTypeName(i).equals("text")) {
                    StringBuffer sbf = new StringBuffer();
                    java.io.InputStream ins = rs.getAsciiStream(i);
                    int ch = 0;
                    if (ins != null) {
                        try {
                            while ((ch = ins.read()) != -1) {
                                sbf.append((char) ch);
                            }
                            ins.close();
                            map.put(rsmd.getColumnName(i), new String(sbf.toString().getBytes("8859_1"), "GB2312"));
                        } catch (IOException ioe) {
                            throw new Exception("...");
                        }
                    } else {
                        map.put(rsmd.getColumnName(i), null);
                    }
                }else{
                    map.put(rsmd.getColumnName(i), rs.getObject(i));
                }
            }
            getListResult().add(map);
        }
    } catch (SQLException se) {
        throw new Exception("...");
    }
    iResult = getListResult().size();
    logger.debug("executeQuery:" + sql + ",successe.");
} finally {
    closeConnection();
}

不需要实体类直接用SQL查询然后自己将查询出的object 对象封装成VO 就行了

类型一个单表向导,和表里有哪些字段无关的.
很多公司的框架里,有通过数据库的任何一个表,动态把字段读出来,然后配置一下,就能在JSP页面上显示相应的数据.
楼主的需求应该是类型于这个.

表的话你建立一个实体类就ok，写下属性。再写set和get方法。就ok了。我这里这张表是学生表，字段是StudNo，StudName,StudSex,ClassID，对应的实体类如下：package com.studinfoms.util;import java.util.Date;public class StudInfo {
private String StudName;
private String StudSex;
private Date StudBirthDay;
private String StudNo;
private String ClassID;
public String getStudName() {
return StudName;
}
public void setStudName(String studName) {
StudName = studName;
}
public String getStudSex() {
return StudSex;
}
public void setStudSex(String studSex) {
StudSex = studSex;
}
public Date getStudBirthDay() {
return StudBirthDay;
}
public void setStudBirthDay(Date studBirthDay) {
StudBirthDay = studBirthDay;
}
public String getStudNo() {
return StudNo;
}
public void setStudNo(String studNo) {
StudNo = studNo;
}
public String getClassID() {
return ClassID;
}
public void setClassID(String classID) {
ClassID = classID;
}
}
下面是jdbc的实现：
public ArrayList<StudInfo> selectStudInfo(String keyword,String search){
String drv="com.microsoft.sqlserver.jdbc.SQLServerDriver";
String url="jdbc:sqlserver://localhost:1433;DatabaseName=test";
String usr="sa";
String password="dongxiaolong1202";

Connection conn=null;
Statement stm=null;
ResultSet rs=null;
ArrayList<StudInfo> list=new ArrayList<StudInfo>();
try {
Class.forName(drv).newInstance();
conn=DriverManager.getConnection(url,usr,password);
System.out.println("数据库连接成功！");
String sqlstr="select * from StudInfo where "+keyword+" like '%"+search+"%'";
System.out.println(sqlstr);
stm=conn.createStatement();
rs=stm.executeQuery(sqlstr);
while(rs.next())
{
StudInfo stud=new StudInfo();
stud.setStudName(rs.getString("StudName"));
stud.setStudNo(rs.getString("StudNo"));
stud.setStudSex(rs.getString("StudSex"));
list.add(stud);
}
} catch (InstantiationException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IllegalAccessException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (ClassNotFoundException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
return list;
}
在servlet中调用方法实现传到jsp中
public void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
System.out.println("doPost");
request.setCharacterEncoding("utf-8");
String keyword=request.getParameter("keyword");
String search=request.getParameter("search");
ArrayList<StudInfo> list=selectStudInfo(keyword, search);
Iterator<StudInfo> iterator=c.iterator();
while(iterator.hasNext()){
StudInfo stud=new StudInfo();
stud=(StudInfo)iterator.next();
System.out.println("-------------------------------------------------------------------------------");
System.out.println("学生学号"+stud.getStudNo());
System.out.println("学生姓名"+stud.getStudName());
System.out.println("学生性别"+stud.getStudSex());
System.out.println(".......................................................................");
}
response.sendRedirect("/studinfoms/selectstudinfook.jsp");//转下jsp页面！
}
如果你满意请记得给我分数哇！不懂你再说。

6楼的好像不怎么对吧，他这个表是用jdbc的sql语句创建的，可能未必知道这么多信息的。难道你的意思是，创建了这么一个实体bean来备用？如果是这样子的话，那可能是行的。就是换个位子思考下，你就当你的那张用sql语句创建的表是一张虚拟的表，就是当某个时候这张表存在的时候，就可以使用这个实体bean了。其实，说白了就一句话，这个用sql语句创建的表，到时候也是会存在于数据库中的，你可以创建一个实体的bean来备用。

1 楼那个方式可以，你可以用界面显示信息的索引来做map的key

给个简单的例子你看一下估计就懂了：
<%@ page language="java" import="java.sql.*"
contentType="text/html; charset=UTF-8" pageEncoding="UTF-8"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type"
content="text/html; charset=ISO-8859-1">
<title>进厂煤计量盈亏月报</title> <%
Connection conn = null;
Statement stat = null;
ResultSet rs = null;
String sql = "";
try {
Class.forName("oracle.jdbc.driver.OracleDriver").newInstance();
String url = "jdbc:oracle:thin:@211.69.205.29:1521:HCDC";
String user = "system";
String password = "manager";
sql = "select ghbh,gmdw,gmkb,fz,hm,zldw from hc_ghjld where ghbh like '"+"201012%"+"'";
conn = DriverManager.getConnection(url, user, password);
stat = conn.createStatement();
rs = stat.executeQuery(sql);
} catch (Exception ex) {
ex.printStackTrace();
out.print("查询数据库出错!");
}
%> </head>
<style type="text/css">
body {
color: #4f6b72;
background: #E6EAE9;
}tr {
background-color: #FFFFFF;
}td {
font-size: 12px;
text-align: center;
color: #4f6b72;
border-right: 1px solid #C1DAD7;
border-bottom: 1px solid #C1DAD7;
padding: 4px 4px 4px 4px;
}
</style>
<body> <table id="tableTest" border="0" cellspacing="1" width="400">
 <tr>
<td rowspan="2" width="100">
矿别
</td>
<td rowspan="2" width="100">
供煤单位
</td>
<td rowspan="2" width="100">
发站
</td>
<td colspan="4" width="320">
货名
</td>
<td rowspan="2" width="100">
重量单位
</td>
</tr>
<%
try {
while (rs.next()) {
out.print("<tr><td>" + rs.getString("ghbh")+ "</td>");
out.print("<td>" + rs.getString("gmdw") + "</td>");
out.print("<td>" + rs.getString("gmkb") + "</td>");
out.print("<td>" + rs.getString("fz") + "</td>");
out.print("<td>" + rs.getString("hm") + "</td>");
out.print("<td>" + rs.getString("zldw")
+ "</td></tr>");
}
} catch (SQLException ex) {
ex.printStackTrace();
out.print("生成表格出错!");
}
%>
</table> </body>
</html>

主要是看下面的红色部分：
<%@ page language="java" import="java.sql.*"
contentType="text/html; charset=UTF-8" pageEncoding="UTF-8"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type"
content="text/html; charset=ISO-8859-1">
<title>进厂煤计量盈亏月报</title> <%
Connection conn = null;
Statement stat = null;
ResultSet rs = null;
String sql = "";
try {
Class.forName("oracle.jdbc.driver.OracleDriver").newInstance();
String url = "jdbc:oracle:thin:@211.69.205.29:1521:HCDC";
String user = "system";
String password = "manager";
sql = "select ghbh,gmdw,gmkb,fz,hm,zldw from hc_ghjld where ghbh like '"+"201012%"+"'";
conn = DriverManager.getConnection(url, user, password);
stat = conn.createStatement();
rs = stat.executeQuery(sql);
} catch (Exception ex) {
ex.printStackTrace();
out.print("查询数据库出错!");
} %> </head>
<style type="text/css">
body {
color: #4f6b72;
background: #E6EAE9;
}tr {
background-color: #FFFFFF;
}td {
font-size: 12px;
text-align: center;
color: #4f6b72;
border-right: 1px solid #C1DAD7;
border-bottom: 1px solid #C1DAD7;
padding: 4px 4px 4px 4px;
}
</style>
<body> <table id="tableTest" border="0" cellspacing="1" width="400">
 <tr>
<td rowspan="2" width="100">
矿别
</td>
<td rowspan="2" width="100">
供煤单位
</td>
<td rowspan="2" width="100">
发站
</td>
<td colspan="4" width="320">
货名
</td>
<td rowspan="2" width="100">
重量单位
</td>
</tr>
<%
try {
while (rs.next()) {
out.print("<tr><td>" + rs.getString("ghbh")
+ "</td>");
out.print("<td>" + rs.getString("gmdw") + "</td>");
out.print("<td>" + rs.getString("gmkb") + "</td>");
out.print("<td>" + rs.getString("fz") + "</td>");
out.print("<td>" + rs.getString("hm") + "</td>");
out.print("<td>" + rs.getString("zldw")
+ "</td></tr>");
}
} catch (SQLException ex) {
ex.printStackTrace();
out.print("生成表格出错!");
} %>
</table> </body>
</html>

调试易

JDBC从数据库中取值

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