学步园

这次的设计也算是失败了百分之40的，不过拿来练手也确实是学到了很多东西，学会了解决问题的很多不通的方法，整个系统是一个子集而已，还需要很多完善，而且想做一个高仿的，看来还是需要继续改进，最近又要忙了，自己给自己打气，晓儿，你加油哦！

package com.youngershen.mrp;<br /> import java.util.*;<br /> import java.sql.*;</p> <p>//°ÑžÃÀàÉèÖóɵ¥ÀûÀ࣬ÌṩÕûžö³ÌÐòµÄºËÐÄÂߌ­œá¹¹<br /> public class MrpCore{</p> <p> private ArrayList<Student> loadFromDB = new ArrayList<Student>();<br /> private String username = "root";<br /> private String password = "leon94941";<br /> private String host = "jdbc:mysql://127.0.0.1:3306/school";<br /> //Connection conn = null;<br /> // Statement state = null ;<br /> // ResultSet rs = null;</p> <p> //ListIterator<Student> indexItem = loadFromDB.listIterator();<br /> private ListIterator<Student> indexItem;</p> <p> //ÓÃÓÚË÷ÒýÈ«ŸÖµÄÊýŸÝËùÔÚµÄλÖÃ</p> <p> private static MrpCore instance = null ;</p> <p> public static MrpCore getInstance(){</p> <p> if(instance == null)</p> <p> instance = new MrpCore();</p> <p> return instance;<br /> }</p> <p> public void writeToDB(){</p> <p> ResultSet result = null;</p> <p> try{<br /> Connection conn = DriverManager.getConnection(host,username,password);</p> <p> Statement state = conn.createStatement();<br /> //ÖŽÐвÙ×÷µÄsqlÓïŸä<br /> String sql = "delete from student";<br /> state.execute(sql);<br /> Iterator<Student> it = loadFromDB.iterator();<br /> while(it.hasNext()){</p> <p> state.clearBatch();//Çå¿Õµ±Ç°µÄÃüÁîÁÐ±í£»</p> <p> Student temp = it.next();<br /> String name = temp.getName();<br /> String age = temp.getAge();<br /> String sex = temp.getSex();<br /> String id = temp.getID();<br /> String cla = temp.getClasss();<br /> String grade = temp.getGrade();<br /> String location = temp.getLocation();</p> <p> sql ="insert into student values"+"("+"/""+id+"/""+","+"/""+name+"/""+","+"/""+sex+"/""+","+"/""+age+"/""+","+"/""+grade+"/""+","+"/""+cla+"/""+","+"/""+location+"/""+")"+";";</p> <p> state.execute(sql);<br /> System.out.println(sql);<br /> }<br /> }</p> <p> catch(SQLException e){<br /> System.out.println("fuck");<br /> e.printStackTrace();<br /> }catch(Exception e){</p> <p> System.out.println("you");<br /> e.printStackTrace();<br /> }</p> <p> }<br /> public void updateToDB(int id,String name,String age,String sex,String grade,String cla,String location){</p> <p> try{<br /> // UPDATE ±íÃû SET ×Ö¶ÎÃû1=¡¯a',×Ö¶ÎÃû2=¡¯b¡¯ WHERE ×Ö¶ÎÃû3=¡¯c';</p> <p> Connection conn = DriverManager.getConnection(host,username,password);</p> <p> Statement state = conn.createStatement();<br /> //ÖŽÐвÙ×÷µÄsqlÓïŸä<br /> String sql = "update student set name="+"/'"+name+"/'"+","+"age="+"/'"+age+"/'"+","+"sex="+"/'"+sex+"/'"+","+"grade="+"/'"+grade+"/'"+","+"class="+"/'"+cla+"/'"+","+"location="+"/'"+location+"/'"+"where id="+"/'"+id+"/'"+";";</p> <p> System.out.println(sql);<br /> state.execute(sql);<br /> }</p> <p> catch(SQLException e){</p> <p> System.out.println("fuck");</p> <p> e.printStackTrace();</p> <p> }catch(Exception e){</p> <p> System.out.println("you");</p> <p> e.printStackTrace();<br /> }</p> <p> }</p> <p> public Student showStudentItem(int flag){</p> <p> if(flag>0){</p> <p> // indexItem.remove();<br /> return indexItem.next();<br /> }<br /> else {</p> <p> //indexItem.remove();<br /> return indexItem.previous();</p> <p> }<br /> }</p> <p> /*<br /> public Student showStudentItemReplaceMethod(int index){</p> <p> // if(loadFromDB.size())</p> <p> }<br /> */<br /> public void loadStudentFromDB(){</p> <p> //Çå¿ÕŒ¯ºÏÀàÖеÄËùÓÐÊýŸÝ£¬ÒÔ±ãÖØÐÂŽÓÊýŸÝ¿âÖжÁÈ¡È«²¿ÊýŸÝ<br /> ResultSet result = null;</p> <p> loadFromDB.clear();</p> <p> try{<br /> Connection conn = DriverManager.getConnection(host,username,password);</p> <p> Statement state = conn.createStatement();<br /> //ÖŽÐвÙ×÷µÄsqlÓïŸä</p> <p> String sql = "select * from student";</p> <p> result = state.executeQuery(sql);</p> <p> //¿éœáÊø<br /> // result.first();<br /> }</p> <p> catch(SQLException e){<br /> System.out.println("fuck");<br /> e.printStackTrace();<br /> }catch(Exception e){</p> <p> System.out.println("you");<br /> e.printStackTrace();<br /> }</p> <p> //String name = null;<br /> try{</p> <p> while(result.next()){</p> <p> String name = null;<br /> String age = null;<br /> String id = null;<br /> String sex = null;<br /> String cla = null;<br /> String grade = null;<br /> String location = null;<br /> // String id = null;</p> <p> name = result.getString("name");<br /> name = new String(name.getBytes("ISO-8859-1"),"GB2312");</p> <p> //id= result.getString("id");<br /> // id = new String(id.getBytes("ISO-8859-1"),"GB2312");</p> <p> //age = result.getInt("age");<br /> age = new String(name.getBytes("ISO-8859-1"),"GB2312");<br /> age = new String(age.getBytes("ISO-8859-1"),"GB2312");</p> <p> id = result.getString("id");<br /> id = new String(id.getBytes("ISO-8859-1"),"GB2312");</p> <p> sex = result.getString("sex");<br /> sex = new String(sex.getBytes("ISO-8859-1"),"GB2312");</p> <p> cla = result.getString("class");<br /> cla = new String(cla.getBytes("ISO-8859-1"),"GB2312");</p> <p> grade = result.getString("grade");<br /> grade = new String(grade.getBytes("ISO-8859-1"),"GB2312");</p> <p> location = result.getString("location");<br /> location = new String(location.getBytes("ISO-8859-1"),"GB2312");</p> <p> //System.out.println(result.getString("id")+"/t"+name);</p> <p> //ŒÓÈëÄÚŽæµÄŒ¯ºÏœá¹¹ÖÐ</p> <p> Student temp = new Student(id,name,age,sex,location,cla,grade);<br /> // temp.showMeEveryThing();<br /> //System.out.println(temp.toString());</p> <p> loadFromDB.add(temp);</p> <p> // System.out.println("size is"+loadFromDB.size());</p> <p> }<br /> }catch(SQLException e){<br /> System.out.println("love");<br /> e.printStackTrace();<br /> }<br /> catch(Exception e){</p> <p> System.out.println("hate");<br /> e.printStackTrace();<br /> }<br /> //rs.close();<br /> // conn.close();</p> <p> }</p> <p> private static void getConnected(){</p> <p> String driver = "com.mysql.jdbc.Driver";<br /> // URLÖžÏòÒª·ÃÎʵÄÊýŸÝ¿âÃûschool<br /> String url = "jdbc:mysql://127.0.0.1:3306/school";<br /> // MySQLÅäÖÃʱµÄÓû§Ãû<br /> String user = "root";<br /> // MySQLÅäÖÃʱµÄÃÜÂë<br /> String password = "leon94941";<br /> try {<br /> // ŒÓÔØÇý¶¯³ÌÐò<br /> Class.forName(driver);<br /> // Á¬ÐøÊýŸÝ¿â<br /> Connection conn = DriverManager.getConnection(url, user, password);<br /> if(!conn.isClosed())<br /> System.out.println("Succeeded connecting to the Database!");</p> <p> } catch(ClassNotFoundException e) {</p> <p> System.out.println("Sorry,can`t find the Driver!");<br /> e.printStackTrace();</p> <p> } catch(SQLException e) {</p> <p> e.printStackTrace();</p> <p> } catch(Exception e) {</p> <p> e.printStackTrace();</p> <p> } </p> <p> }</p> <p> public ArrayList<Student> getStudentData(){</p> <p> return loadFromDB;</p> <p> }</p> <p> public void addStudent(Student s){</p> <p> loadFromDB.add(s);</p> <p> } </p> <p> public void flashIterator(){</p> <p> indexItem.remove(); </p> <p> }<br /> private MrpCore(){<br /> System.out.println("s");<br /> getConnected();<br /> loadStudentFromDB();<br /> indexItem = loadFromDB.listIterator();<br /> System.out.println(loadFromDB.size());</p> <p> }</p> <p> public static void main(String[] args){</p> <p> MrpCore mc = MrpCore.getInstance();<br /> System.out.println(mc.getStudentData().size());<br /> // System.out.println(mc.showStudentItem(-1));<br /> mc.writeToDB();</p> <p> } </p> <p> }<br />