有时要为每一篇文章统计其点击次数,如果每一次浏览都要更新一次库的话,那性能在访问量很大的情况下,服务器的压力就会很大了,比较好一点的方法就是先将要更新的数据缓存起来,然后每隔一段时间再利用数据库的批量处理,批量更新库。源码如下: ~bpgSP"
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CountBean.java {f p[BF
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/* wUM0M?_p[
* CountData.java '4<1 1(U
* ?Ss!e$jf
* Created on 2007年1月1日, 下午4:44 K~EmD9
* pmYHUj
#
* To change this template, choose Tools | Options and locate the template under r,2g^K)6
* the Source Creation and Management node. Right-click the template and choose Uoix
* Open. You can then make changes to the template in the Source Editor. 3irl
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*/ yEQs:v6L~
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package com.tot.count; ;]:@n;c\
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/** Srd4))2/0
* ]
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* @author *DhiN
*/ J<lO=
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public class CountBean { Y\'}a+:@Ph
private String countType; IEvdV6{K
int countId; sW8dPw
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/** Creates a new instance of CountData */ 13/]DF,S"^
public CountBean() {} jZrq{Z<
public void setCountType(String countTypes){ B4 }bVjs
this.countType=countTypes; ~4cC/"q$X
} '@P^0+B!(.
public void setCountId(int countIds){ K!l5coM
this.countId=countIds; )@bQu~Y
} ,~W|]/b<q
public String getCountType(){ %D "I
return countType; mpJ#:}n
} e\75:oQ
public int getCountId(){ E8&TO~"a]e
return countId; U:_^#\p
} IIx#2r
} qJUK_6|3
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CountCache.java |LKXOU
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/* 8}| (0mC
* CountCache.java xKp4*[}m
* k|d+#u[Mj@
* Created on 2007年1月1日, 下午5:01 }JAG7L&{
* <Q?F?.^e
* To change this template, choose Tools | Options and locate the template under >[*qf9$
* the Source Creation and Management node. Right-click the template and choose (dSL7nel;L
* Open. You can then make changes to the template in the Source Editor. 0{ R=9wcc
*/ ,zY$8y]
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package com.tot.count; cYt!n5w~W
import java.util.*; N] sAji*
/** 12LL48bi
* *;*r8[U}q
* @author a:6m7U)P#5
*/ 4{`{WI{
public class CountCache { ^y%T~dLkp'
public static LinkedList list=new LinkedList(); +srGN5!
/** Creates a new instance of CountCache */ V~5jfcd
public CountCache() {} [ibu/W$
public static void add(CountBean cb){ |
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if(cb!=null){ =C.$
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list.add(cb); <UQbt N-B\
} ixD)VcD-f
} HA>OkA/
} oILZgNe'
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CountControl.java @I!0-OjL
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/* ,\%c^,HLJ
* CountThread.java ) hfpwdQ
* 6,{$J
* Created on 2007年1月1日, 下午4:57 Npy:!
* 65Yv4pNL
* To change this template, choose Tools | Options and locate the template under ,nDaqQ-C!!
* the Source Creation and Management node. Right-click the template and choose a!AA]
* Open. You can then make changes to the template in the Source Editor. rh}J3S5vp
*/ 6j LCU%^
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package com.tot.count; V33T+P~j
import tot.db.DBUtils; WEi2=3dV
import java.sql.*; [3|P 7?W/
/** v
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* ^3L0w}#
* @author YteO6A;
*/ 'AH0ww_)n
public class CountControl{ VS8Rx.?
private static long lastExecuteTime=0;//上次更新时间 #'9HU2
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 F@B]et7
/** Creates a new instance of CountThread */ b!5~7Ub.No
public CountControl() {} Zba2d,8/
public synchronized void executeUpdate(){ E#N|wq
Connection conn=null; 7! INkH]
PreparedStatement ps=null; n8ZZ#}Nhg
try{ n]o<S+z
conn = DBUtils.getConnection(); Cd}<a?m,
conn.setAutoCommit(false); LuvY<~u
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); 5uj?#)N
for(int i=0;i<CountCache.list.size();i++){ 6zuTQ^pz
CountBean cb=(CountBean)CountCache.list.getFirst(); t=W}SH
CountCache.list.removeFirst(); JO6)-U$7UG
ps.setInt(1, cb.getCountId()); +*/Zu`kzX
ps.executeUpdate();⑴ 0[?Xxk}s0
//ps.addBatch();⑵ pYmk1!]/
} R)s:rJQ=p
//int [] counts = ps.executeBatch();⑶ a'yK~;+_9
conn.commit(); @>Km_Ax
}catch(Exception e){ Tqn@P
e.printStackTrace(); ud@%5d
} finally{ DAr1C+Dy
try{ ra
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if(ps!=null) { ;RPx^X~
ps.clearParameters(); M\Ye<Tk
ps.close(); !9VY|&fHe
ps=null; !Pfr,a
} ['tY4$L(
}catch(SQLException e){} wIaony
DBUtils.closeConnection(conn);
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} xHLlMn4M
} bI9~jWgGp
public long getLast(){ ag;pN*z
return lastExecuteTime; .2Elr(&*h
} 1FL~ndJs
public void run(){ 2E)-M9ds
long now = System.currentTimeMillis(); bUdLs.:
if ((now - lastExecuteTime) > executeSep) { fW1CFRHH
//System.out.print("lastExecuteTime:"+lastExecuteTime); 3J|F?M"N7
//System.out.print(" now:"+now+"\n"); Q6!zZ))~
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); V1`o%;j
lastExecuteTime=now; WUXx;9 >
executeUpdate(); :g=qz~2Xk
} 6@F9G4<Z
else{ $2M$?4S/T
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); u5b|#&-mX
} U-(01-
} X Dm[Gc>(~
} /cQueUME`
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 =M[bnq*\
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类写好了,下面是在JSP中如下调用。 Q}K"24`=
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<% Ru!iR#s)!
CountBean cb=new CountBean(); S8wLmd>
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); JWhdMU
CountCache.add(cb); dI@(<R
out.print(CountCache.list.size()+"<br>"); %XoiVlT@:
CountControl c=new CountControl(); kY|utoAP
c.run(); Zd}9O jz5
out.print(CountCache.list.size()+"<br>"); }1c|gQ
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