下面是查询数据库的代码数据库
public boolean Seekaim(SeekUser seekid){
String word="select * from seeker where userID like '%"+seekid.getSeek_name()+"%'";//生成一条sql语句
try {
Statement statement=connection.createStatement();//创建一个Statement对象
ResultSet resultSet=statement.executeQuery(word);//查询数据可通过Statement接口的executeQuery()方法执行SQL语句
//executeQuery()方法用于执行SELECT查询语句，将放回一个ResultSet型的结果集。通过遍历查询结果集的内容，才可获取SQL语句执行的查询结果。
//定义三个string类型的量
String id,name;
while(resultSet.next()){//遍历结果集
id=resultSet.getString("userID");
System.out.println("查询的用户是"+id);
name=resultSet.getString("userName");
System.out.println("查询用户的昵称是"+name);
}
/*
1：Result接口类似于一个临时表，用来暂时存放数据库查询操作所获得的结果集。
2：PreparedStatement接口中的excuteQuery（）方法,在此PreparedStatement对象执行sql查询语句，返回结果为查询结果集Result对象
3：next()将指针向下移一行
4：ResultSet对象的getXXX()方法可获取查询结果集中数据。由于ResultSet中保存的数据是表的形式，因此可通过使用getXXX()方法指定列的序号与列的名称。
id=rs.getInt("id");//获得id
username=rs.getString(2);//
password=rs.getString("password");//
age=rs.getInt(4);//
sex=rs.getInt(5);//
仔细体会就可以明白，getXXX(参数)；参数既可以是列的名称还可以是第几列的数字。
*/
if (resultSet.next())//resultSet.next()；如果为真代表查询结果有值，为假代表查询结果没有值
{
return true;
}
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
return false;
}
已经查到了想要的数据，现在想把数据返回给安卓客户端我要怎么写呀，顺便贴上servlet的代码
import java.io.DataOutputStream;
import java.io.IOException;
import java.io.PrintWriter;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
public class SeekServlet extends HttpServlet {
/**
* Constructor of the object.
*/
public SeekServlet() {
super();
}
/**
* Destruction of the servlet. <br>
*/
public void destroy() {
super.destroy(); // Just puts "destroy" string in log
// Put your code here
}
/**
* The doGet method of the servlet. <br>
*
* This method is called when a form has its tag value method equals to get.
*
* @param request the request send by the client to the server
* @param response the response send by the server to the client
* @throws ServletException if an error occurred
* @throws IOException if an error occurred
*/
public void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
//获取request中的参数（登陆）括号里面是安卓客户端里面构建url时写入的参数，保持一致,绿色的那个
/*
*********************************搜索用户******************************************************************
*/
//获取request中的参数
String seek_id = request.getParameter("edit_id");
//接收客户端消息处理
SeekUser seek3=new SeekUser();
seek3.setSeek_name(seek_id);
//向数据库查询对象
MyDB_user mUser3=new MyDB_user();
mUser3.Seekaim(seek3);
//返回查询结果
//创建一个DataOutputStream对象
DataOutputStream dos1=new DataOutputStream(response.getOutputStream());
if(mUser3.Seekaim(seek3))
{
}
}
/**
* The doPost method of the servlet. <br>
*
* This method is called when a form has its tag value method equals to post.
*
* @param request the request send by the client to the server
* @param response the response send by the server to the client
* @throws ServletException if an error occurred
* @throws IOException if an error occurred
*/
public void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
// 输出流
PrintWriter out = response.getWriter();
// 设置编码形式
request.setCharacterEncoding("utf-8");
response.setCharacterEncoding("utf-8");
// 获取传入的数据
String id = request.getParameter("id");
System.out.println("UserInfoServlet: id = " + id);
}
/**
* Initialization of the servlet. <br>
*
* @throws ServletException if an error occurs
*/
public void init() throws ServletException {
// Put your code here
}
}
查询的结果已经可以遍历出来了但是不知道怎么传回给安卓端。Seekaim方法是在servlet中调用的有没有大佬来拯救一下小菜鸡
