• 第七周JSP增删改查


    package ak74;
    
    public class Haoshu {
    package ak74;
    
    import java.sql.Connection;
    import java.sql.DriverManager;
    import java.sql.ResultSet;
    import java.sql.SQLException;
    import java.sql.Statement;
    
    import com.mysql.jdbc.Driver;
    
    public class JDBCUtils {
         //创建工具类   方便使用
    	//获取连接
    	 public static Connection getCon() throws Exception{
    		 
    		  Class.forName( "com.mysql.jdbc.Driver");
    		  
    		Connection con=DriverManager.getConnection("jdbc:mysql://localhost:3306/mysql?useSSL=false", "root", "guoshaofeng");
    		return con;
    	 }
    	 
    	//关闭数据流
    	 public static void  realse(ResultSet rst,Statement st,Connection con){
    		 if(rst!=null){
    				try {
    					rst.close();
    				} catch (SQLException e) {
    					// TODO Auto-generated catch block
    					e.printStackTrace();
    				}
    				}
    				if(st!=null){
    				try {
    					st.close();
    				} catch (SQLException e) {
    					// TODO Auto-generated catch block
    					e.printStackTrace();
    				}
    				}
    				if(con!=null){
    				try {
    					con.close();
    				} catch (SQLException e) {
    					// TODO Auto-generated catch block
    					e.printStackTrace();
    				}
    				}
    	 }
    	 
    	 
    }
    

      

    package ak74;
    
    import java.sql.Connection;
    import java.sql.PreparedStatement;
    import java.sql.ResultSet;
    
    import java.sql.Statement;
    import java.util.ArrayList;
    import java.util.List;
    
    
    
    public class HaoshuDao {
    
    	private List<Haoshu> list;
    
    
    
    
    
    	/**
    	 * @param args
    	 */
    	//增加
       public boolean insert(Haoshu haoshu){
    	    Statement st=null;
    	    Connection con=null;
    	   
    	   try{
    		   con=JDBCUtils.getCon();
    		   
    		   st=con.createStatement();
    		   
    		   String sql="insert into  haoshu "+"values('"
    		   +haoshu.getId()+"','"
    		   +haoshu.getName()+"','"
    		   +haoshu.getMvp()+"','"
    		   +haoshu.getChenghao()+"'"
    		   +")";
    		 
    		   int row=st.executeUpdate(sql);
    		   if(row==1){
    			   return true;
    		   }
    				   
    	     
    		   
    	   }catch(Exception e){
    		   throw new RuntimeException(e);
    	   }
    	   
    	   finally{
    		   JDBCUtils.realse(null, st, con);
    	   }
    	   
    	   
    	   
    	
    	return false;
       }
       
       
       
       
       
     //查询所有
    
       
       public List<Haoshu> FindAllHaoshu(){
    	     Connection con=null;
    	     Statement st=null;
    	     ResultSet rst=null;
    	   try{
    		con= JDBCUtils.getCon();
    		
    		st=con.createStatement();
    		
    		String sql="select*from haoshu;";
    		
    		rst=st.executeQuery(sql);
    		
    		List<Haoshu> list=new ArrayList<Haoshu>();
    		   while(rst.next()){
    			   Haoshu  haoshu=new Haoshu();
    			   haoshu.setId(rst.getInt("id"));
    			   haoshu.setName(rst.getString("name"));
    			   haoshu.setMvp(rst.getString("mvp"));
    			   haoshu.setChenghao(rst.getString("chenghao"));
    			    list.add(haoshu);
    		   }
    		   return list;
    	   }catch(Exception e){
    		   throw new RuntimeException(e);  
    	   }
    	   finally{
    		   JDBCUtils.realse(rst, st, con);
    	   }
    	   
    
       }
       
       
       
       //根据ID来查询记录
       public Haoshu FindHaoshuByid(int id){
    	     Connection con=null;
    	    PreparedStatement st=null;
    	     ResultSet rst=null;
    	   try{
    		con= JDBCUtils.getCon();
    		
    		
    		String sql="select*from haoshu where id=?;";
    		st=con.prepareStatement(sql);
    		
                st.setInt(1, id);
    		
    		rst=st.executeQuery();
    		
    
    		 if(rst.next()){
    			   Haoshu  haoshu=new Haoshu();
    			   haoshu.setId(rst.getInt("id"));
    			   haoshu.setName(rst.getString("name"));
    			   haoshu.setMvp(rst.getString("mvp"));
    			   haoshu.setChenghao(rst.getString("chenghao"));
    			 
    			    return haoshu;
    		   }
    		   
    	   }catch(Exception e){
    		   throw new RuntimeException(e);  
    	   }
    	   finally{
    		   JDBCUtils.realse(rst, st, con);
    	   }
    	   
                return null;
     }
       
       
       //根据id修改name和mvp
       public boolean Update(Haoshu haoshu){
    	    PreparedStatement st=null;
    	    Connection con=null;
    	   
    	   try{
    		   con=JDBCUtils.getCon();
    		   String sql="update haoshu set name=?,mvp=? where id=?";
    		   st=con.prepareStatement(sql);
    		   
    
    	       st.setString(1, haoshu.getName());
    	       st.setString(2, haoshu.getMvp());
    	       st.setInt(3, haoshu.getId());
    		   int row=st.executeUpdate();
    		   if(row==1){
    			   return true;
    		   }
    				   
    	     
    		   
    	   }catch(Exception e){
    		   throw new RuntimeException(e);
    	   }
    	   
    	   finally{
    		   JDBCUtils.realse(null, st, con);
    	   }
    	   
    	   
    	   
    	
    	return false;
      }
      
      //根据id删除  
      public boolean Delete(int id){
    	  PreparedStatement st=null;
    	    Connection con=null;
    	   
    	   try{
    		   con=JDBCUtils.getCon();
    		   String sql="delete from haoshu where id=?";
    		   st=con.prepareStatement(sql);
    		   
    
    	       st.setInt(1, id);
    	 
    		   int row=st.executeUpdate();
    		   if(row==1){
    			   return true;
    		   }
    				   
    	     
    		   
    	   }catch(Exception e){
    		   throw new RuntimeException(e);
    	   }
    	   
    	   finally{
    		   JDBCUtils.realse(null, st, con);
    	   }
    	   
    	   
    	   
    	
    	return false;
    	  
      }
      
    }
    
    
    
     
    

      

    package ak74;
    
    public class JdbcInsertText {
    
    	/**
    	 * @param args
    	 */
         
    	public static void main(String[] args) {
    		// TODO Auto-generated method stub
              HaoshuDao  dao=new HaoshuDao();
              Haoshu haoshu=new Haoshu();
              haoshu.setId(6);
              haoshu.setName("兰亭集序");
              haoshu.setMvp("王小姐");
              haoshu.setChenghao("GXJ");
              dao.insert(haoshu) ;
    	}
    
    }
    

      

    package ak74;
    
    public class FindHaoshuByid {
    
    	/**
    	 * @param args
    	 */
    	public static void main(String[] args) {
    		// TODO Auto-generated method stub
               HaoshuDao  dao=new HaoshuDao();
               Haoshu h= dao.FindHaoshuByid(6);
               System.out.println(h.getName());
    	}
    
    }
    

      

    package ak74;
    
    public class Update {
    
    	/**
    	 * @param args
    	 */
    	public static void main(String[] args) {
    		// TODO Auto-generated method stub
             HaoshuDao  dao=new HaoshuDao();
             
              Haoshu hh=new Haoshu();
              hh.setId(6);
              hh.setName("徐凤年");
              hh.setMvp("bl");
              boolean b=dao.Update(hh);
              System.out.println(b);
    	}
    
    }
    

      

    package ak74;
    
    public class Delete {
    
    	/**
    	 * @param args
    	 */
    	public static void main(String[] args) {
    		// TODO Auto-generated method stub
          HaoshuDao  dao=new HaoshuDao();
          boolean bb=dao.Delete(2);
          System.out.println(bb);
    	}
    
    }
    

      

    /** * @param args */ //一,创建JavaBean用来封装用户数据 private int id; private String name; private String mvp; private String chenghao; public int getId() { return id; } public void setId(int id) { this.id = id; } public String getName() { return name; } public void setName(String name) { this.name = name; } public String getMvp() { return mvp; } public void setMvp(String mvp) { this.mvp = mvp; } public String getChenghao() { return chenghao; } public void setChenghao(String chenghao) { this.chenghao = chenghao; } public static void main(String[] args) { // TODO Auto-generated method stub } }

      

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  • 原文地址:https://www.cnblogs.com/gsfwxj1820/p/12743547.html
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