rs = dbMeta.getTables(null, null, null, new String[]{"TABLE"});//表示的是type的类型是table类型
out.println("<form action=\"getdameta\" method= \"get\">");
out.println("<select size=1 name=tablename>");
while(rs.next()){
out.println("<option value="+rs.getString("TABLE_NAME"));
out.println(rs.getString("TABLE_NAME"));
out.println("</option>");
}
out.println("</select><p>");
out.println("<input type=\"submit\" value=\"提交\">");
out.println("</form>");
out.println("</body></html>");
out.close();首先程序是没有错误的，我可以在tomcat上看到，但是却没有我得到的表名只是这样的（这里好像不能发图片啊）反正出来的页面是
<html><head>
<title>数据库信息</title>
</head><body>
<form action="getdameta" method= "get">
<select size=1 name=tablename>
//这里没有tablename的名称啊，这里是空的
//
</select><p>
<input type="submit" value="提交">
</form>
</body></html>
希望有人告诉一下原因
// 获取所有表
ResultSet tableSet = databaseMetaData.getTables(null, "%", "%",
new String[] { "TABLE" });
import java.sql.*;import javax.servlet.http.*;
import javax.servlet.*;
import java.util.*;/*
*
*/
public class GetdatametaServlet extends HttpServlet {
private String url;
private String user;
private String password;
public void init()throws ServletException{
ServletContext sc = getServletContext();
String driverClass = sc.getInitParameter("driverClass");
url = sc.getInitParameter("url");
user = sc.getInitParameter("user");
password = sc.getInitParameter("password");
try{
Class.forName(driverClass);
}
catch(ClassNotFoundException ce ){
throw new ServletException("加载数据库失败");
}
}
public void doGet(HttpServletRequest request,HttpServletResponse response)
throws ServletException,IOException{
Connection conn = null;
Statement stmt = null;
ResultSet rs = null;
try{
conn = DriverManager.getConnection(url, user, password);
response.setContentType("text/html;charset=gb2312");
PrintWriter out = response.getWriter();
out.println("<html><head>");
out.println("<title>数据库信息</title>");
out.println("</head><body>");
String tablename = request.getParameter("tablename");
if(null==tablename || tablename.equals("")){
stmt = conn.createStatement();
stmt.executeUpdate("use test");
DatabaseMetaData dbMeta = conn.getMetaData();
rs = dbMeta.getTables(null, "%", "%", new String[] { "TABLE" });
if(!rs.next()){
out.println("table列表为空");
out.close();
}
out.println("<form action=\"getdameta\" method= \"get\">");
out.println("<select size=1 name=tablename>");
while(rs.next()){
out.println("<option value="+rs.getString("TABLE_NAME")+">");
out.println(rs.getString("TABLE_NAME"));
out.println("</option>");
}
out.println("</select><p>");
out.println("<input type=\"submit\" value=\"提交\">");
out.println("</form>");
}
else{
stmt = conn.createStatement();
stmt.executeUpdate("use bookstore");
rs = stmt.executeQuery("select * from " +tablename);
ResultSetMetaData rsMeta = rs.getMetaData();
int columnCount = rsMeta.getColumnCount();
out.println("<table border=1>");
out.println("<caption>表的结构</caption>");
out.println("<tr><th>字段名</th><th>字段类型</th><th>最大字符宽度</th></tr>");
ArrayList<String> al = new ArrayList<String>();//创建了一个列表
for(int i =1;i<=columnCount;i++){
out.println("<tr>");
String columnname = rsMeta.getColumnName(i);
out.println("<td>"+columnname+"</td>");
al.add(columnname);
out.println("<td>"+rsMeta.getColumnTypeName(i)+"</td>");
out.println("<td>"+rsMeta.getColumnDisplaySize(i)+"</td>");
}
out.println("</table><p>");
out.println("<table border=1>");
out.println("<caption>表中的数据</caption>");
out.println("<tr>");
for(int i=0;i<columnCount;i++){
out.println("<th>"+al.get(i)+"</th>");
}
while(rs.next()){
out.println("<tr>");
for(int i=1;i<=columnCount;i++){
out.println("<td>"+rs.getString(i)+"</td>");
}
out.println("<tr>");
}
out.println("</table>");
}
out.println("</body></html>");
out.close();
}
catch(SQLException se){
se.printStackTrace();
}
finally{
if(rs!=null){
try{
rs.close();
}
catch(SQLException se){
se.printStackTrace();
}
rs = null;
}
if(stmt!=null){
try{
stmt.close();
}
catch(SQLException se){
se.printStackTrace();
}
stmt=null;
}
if(conn!=null){
try{
conn.close();
}
catch(SQLException se){
se.printStackTrace();
}
conn = null;
}
}
}
}