java access sql
JDBCÁ¬½ÓMySQL
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Class.forName("com.mysql.jdbc.Driver");
Class.forName("com.mysql.jdbc.Driver").newInstance();
JDBC URL ¶¨ÒåÇý¶¯³ÌÐòÓëÊý¾ÝÔ´Ö®¼äµÄÁ¬½Ó
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jdbc:mysql//[hostname][:port]/[dbname][?param1=value1][¶m2=value2]….
ʾÀý£ºjdbc:mysql://localhost:3306/sample_db?user=root&password=your_password
³£¼û²ÎÊý£º
user Óû§Ãû
password ÃÜÂë
autoReconnect Áª»úʧ°Ü£¬ÊÇ·ñÖØÐÂÁª»ú£¨true/false£©
maxReconnect ³¢ÊÔÖØÐÂÁª»ú´ÎÊý
initialTimeout ³¢ÊÔÖØÐÂÁª»ú¼ä¸ô
maxRows ´«»Ø×î´óÐÐÊý
useUnicode ÊÇ·ñʹÓÃUnicode×ÖÌå±àÂ루true/false£©
characterEncoding ºÎÖÖ±àÂ루GB2312/UTF-8/…£©
relaxAutocommit ÊÇ·ñ×Ô¶¯Ìá½»£¨true/false£©
capitalizeTypeNames Êý¾Ý¶¨ÒåµÄÃû³ÆÒÔ´óд±íʾ
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String url="jdbc:mysql://localhost:3306/sample_db?user=root&password=your_password";
Connection con = DriverManager.getConnection(url);
½¨Á¢SQL³ÂÊöʽ¶ÔÏó£¨Statement Object£©
Statement stmt = con.createStatement()£»
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executeQuery()
String query = "select * from test";
ResultSet rs=stmt.executeQuery(query);
½á¹û¼¯ResultSet
while(rs.next())
{rs.getString(1);rs.getInt(2);}
executeUpdate()
String upd="insert into test (id,name) values(1001,xuzhaori)";
int con=stmt.executeUpdate(upd);
execute()
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¡¡1. String.trim()
¡¡¡¡trim()ÊÇÈ¥µôÊ×β¿Õ¸ñ
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¡¡String str = " hell o ";
¡¡¡¡String str2 = str.replaceAll(" ", "");
¡¡¡¡System.out.println(str2);
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import java.awt.*;
import java.awt.event.*;
//¶íÂÞ˹·½¿éÀà
public class ERS_Block extends Frame{
public static boolean isPlay=false;
public static int level=1,score=0;
public static TextField scoreField,levelField;
public static MyTimer timer;
Ga ......
result love(boy, girl)
{
if( boy.Óз¿() and boy.Óгµ() )
{
boy.set(nothing);
return girl.¼Þ¸ø(boy);
&n ......