answeraction.java

它是利用jsp+javabean来编写的

/*
 * AnswerAction.java
 *
 * Created on 2006年8月10日, 上午8:06
 *
 * To change this template, choose Tools | Template Manager
 * and open the template in the editor.
 */

package ACTION;
import java.io.UnsupportedEncodingException;
import java.sql.*;
import PUBLIC.TestSql;
import java.util.Date; 
import java.util.StringTokenizer;
/**
 *
 * @author fish
 */
public class AnswerAction extends TestSql{    //继承TestSql以实现数据库连接部分的代码重用
    ResultSet rs;
    String UserName=null;
    String AnswerContext=null;
    String Result="您尚未登录或登录超时<br><a href='index.jsp'>重新登录</a>";
    int QuestionID;

    public AnswerAction() {
    }
    public void setUserName(String s){  //获得答案递交者的用户名
        UserName=s.trim(); 
    }
    public void setAnswerContext(String c){ //获得答案的内容
        AnswerContext=FormatStr(c); //调用FormatStr对字符串进行转换
    }
    public void setQuestionID(String n){  //获得答案所对应的问题编号
        QuestionID=Integer.parseInt(n.trim());
    }
    public String getResult(){  //答案添加过程
        StringBuffer buffer=new StringBuffer();
        String condition;
        int i = 0;
        if(UserName==null)  //判断用户是否登录
        {
            buffer.append("您尚未登录或登录超时<br><a href='index.jsp'>重新登录</a>");
        }
        else
        {   
             //取出数据库中已经递交过的用户列表
            try {
                condition="SELECT AnswerUser FROM TestAnswer WHERE AnswerQuestionID="+QuestionID;
                rs=sql.executeQuery(condition);
                while(rs.next())
                    if(UserName.equals(rs.getString("AnswerUser").trim()))
                        i++;
            } catch (SQLException ex) {
                buffer.append("递交过的用户列表不存在");
                ex.printStackTrace();
            }
            if(i!=0)
            {
                buffer.append("您已经回答过这个问题了!");
            }
            else{
                //插入新的答案到[TestAnswer]表中
                try {
                    condition="INSERT INTO TestAnswer(AnswerUser,AnswerQuestionID,AnswerTime,AnswerContents) VALUES('"+UserName.trim()+"',"+QuestionID+",NOW(),'"+AnswerContext+"')";
                    sql.executeUpdate(condition);
                    buffer.append("恭喜你,答案添加成功!");
                } catch (SQLException ex) {
                    buffer.append("答案添加失败");
                    ex.printStackTrace();
                }
            }
        }
        Result=new String(buffer);
        return Result;
    }

}