blog 显示博文

BlogServlet.java

package cn.com.blog;

import java.io.IOException;
import java.io.PrintWriter;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.Date;

import javax.naming.InitialContext;
import javax.naming.NamingException;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.sql.DataSource;

import org.apache.commons.dbutils.QueryRunner;

import com.mysql.jdbc.Connection;
import com.mysql.jdbc.Statement;
import com.opensymphony.xwork2.inject.Context;

public class BlogServlet extends HttpServlet {

	public BlogServlet() {
		super();
	}

	public void destroy() {
		super.destroy(); // Just puts "destroy" string in log
		// Put your code here
	}

	public void doGet(HttpServletRequest request, HttpServletResponse response)
			throws ServletException, IOException {

		doPost(request, response);
	}


	public void doPost(HttpServletRequest request, HttpServletResponse response)
			throws ServletException, IOException {

		request.setCharacterEncoding("utf-8");
		String title = request.getParameter("title");
		String content = request.getParameter("content");
		String categoryId = request.getParameter("categoryId");
		
		Date date=new Date();
		int year=date.getYear();
		int month=date.getMonth();
		int day=date.getDay();
		int hour=date.getHours();
		int minute=date.getMinutes();
		int second=date.getSeconds();
	
		String dateString=year+"-"+month+"-"+day;
		dateString+=" "+hour+":"+minute+":"+second;

		int flag = 0;
		java.sql.Connection con;
		try {
			Class.forName("com.mysql.jdbc.Driver");
			con = DriverManager.getConnection(
					"jdbc:mysql://localhost:3306/new_db", "root", "");
			java.sql.Statement stmt = con.createStatement(
					ResultSet.TYPE_SCROLL_INSENSITIVE,
					ResultSet.CONCUR_READ_ONLY);
			String sql = "insert into   blog(title,content,category_id,created_time) VALUES (' "
					+ title
					+ " ', ' "
					+ content
					+ " ', ' "
					+ categoryId
					+ " ', ' "
					+ dateString
					+ "') ";
			flag = stmt.executeUpdate(sql);

		} catch (SQLException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		} catch (ClassNotFoundException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
		String message = null;
		if (flag == 1) {
			message = "添加成功";
		} else {
			message = "添加失败";
		}

		request.setAttribute("message", message);
		request.getRequestDispatcher("/addBlogResult.jsp").forward(request,
				response);

	}

	public void init() throws ServletException {
		// Put your code here
	}

}

GetBlogServlet.java

package cn.com.blog;

import java.io.IOException;
import java.io.PrintWriter;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;

import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

public class GetBlogServlet extends HttpServlet {

	public void doGet(HttpServletRequest request, HttpServletResponse response)
			throws ServletException, IOException {

		request.setCharacterEncoding("utf-8");
		String id = request.getParameter("id");

		java.sql.Connection con;
		ResultSet resultSet = null;
		try {
			Class.forName("com.mysql.jdbc.Driver");
			con = DriverManager.getConnection(
					"jdbc:mysql://localhost:3306/new_db", "root", "");
			java.sql.Statement stmt = con.createStatement(
					ResultSet.TYPE_SCROLL_INSENSITIVE,
					ResultSet.CONCUR_READ_ONLY);
			String sql = "select * from blog where id =" + id;
			System.out.println("1");
			resultSet = stmt.executeQuery(sql);
			System.out.println("2");
			while (resultSet.next()) {
				request.setAttribute("title", resultSet.getString(3));
				request.setAttribute("content", resultSet.getString(4));
				request.setAttribute("created_time", resultSet.getString(5));
			}

		} catch (SQLException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		} catch (ClassNotFoundException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}

		request.getRequestDispatcher("/displayBlog.jsp").forward(request,
				response);

	}

}

让后添加一个displayBlog.jsp的文件

1 在测试servlet 的时候路径要注意，先写工程名字，让后是一个servlet，让后是servlet的名称
http://localhost:8088/liuwei/servlet/GetBlogServlet?id=3


2 如果jdbc语句出现before start of result set。
  那么应该加上一句话
  while(rs.next())
  {


  }