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: IC&P-X_aP
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CountBean.java n'v\2(&uYN
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/* ?/"|tuQMW
* CountData.java cd1G.10
* R8k4?_W?T
* Created on 2007年1月1日, 下午4:44 ~<f[7dBv
* _0v+'&bz
* To change this template, choose Tools | Options and locate the template under sde>LZet/
* the Source Creation and Management node. Right-click the template and choose }VZExqm)
* Open. You can then make changes to the template in the Source Editor. V-}}?c1 F
*/ <M@-|K"Eb
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package com.tot.count; s91[@rh/
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/** 4_kN';a4Q
* tLWw<)t
* @author Bj1%}B
*/ R
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public class CountBean { ];LFv5"
private String countType; 0mujf
int countId; /@k#tdj
/** Creates a new instance of CountData */ M&j|5UH%.
public CountBean() {} ]~I+d/k
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public void setCountType(String countTypes){ ~_vSMX
this.countType=countTypes; Ztg_='n
} 9Q%lS
public void setCountId(int countIds){ s:}? rSI
this.countId=countIds; 'ZW(Hjrd
} }I&.xzJ
public String getCountType(){ ZrTB%
return countType; \]V:>=ry>
} GYfOwV!zB
public int getCountId(){ [|OII!"
return countId; teg5g|*
} HCs^?s8Pp
} +QU>D:l
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CountCache.java E(P
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/* Z5>~l
* CountCache.java D#b*M)X"
* &2y4k"B&)
* Created on 2007年1月1日, 下午5:01 ::oFL#+
* w'2FYe{wj
* To change this template, choose Tools | Options and locate the template under J+`aj8_ B
* the Source Creation and Management node. Right-click the template and choose VTu#)I7A^@
* Open. You can then make changes to the template in the Source Editor. y|}~"^+T
*/ $]We |
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package com.tot.count; ^
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import java.util.*; F'Y ad
/** cRVL1ne
* C7FQc{
* @author y4Jc|)
*/ I_ mus<sE
public class CountCache { js<d"m*
public static LinkedList list=new LinkedList(); @gD)pH
/** Creates a new instance of CountCache */ {*7MT}{(
public CountCache() {} Ai<
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public static void add(CountBean cb){ wQ/* f9
if(cb!=null){ 3F2IL)Hn
list.add(cb); :+ ,;5
} 'RMUjJ-!
} NS[eQ_rT
} ^)Hf%
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CountControl.java R@\}iyM
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/* _]`7et\=
* CountThread.java @.e X8~3=
* >ou=}/<
* Created on 2007年1月1日, 下午4:57 ?{S>%P A_B
* HY)xT$/J
* To change this template, choose Tools | Options and locate the template under <:v+<)K
* the Source Creation and Management node. Right-click the template and choose 8%7%[WC#
* Open. You can then make changes to the template in the Source Editor. !CGX \cvW
*/ "tz6O0D
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package com.tot.count; hpAdoy[
import tot.db.DBUtils; U>E:
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import java.sql.*; fwFJe(.
/** 5?k5J\+
* <k:I2LF_
* @author I\.|\^
*/ DXLXGvcM
public class CountControl{ :<qe2Z5k
private static long lastExecuteTime=0;//上次更新时间 *,\"}x*
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 ?G,4N<]Nu
/** Creates a new instance of CountThread */ >!=@TK(~
public CountControl() {} c@t?R$c
public synchronized void executeUpdate(){ ^c\O,*:
Connection conn=null; $+*nb4
PreparedStatement ps=null; |Kd#pYt%O
try{ ] 3{t}qY$A
conn = DBUtils.getConnection(); 5*YoK)2J
conn.setAutoCommit(false); ENTcTrTn
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); aOzIo-
for(int i=0;i<CountCache.list.size();i++){ iS$[dC ?N
CountBean cb=(CountBean)CountCache.list.getFirst(); !=dz^f.{
CountCache.list.removeFirst(); G?W:O{n3
ps.setInt(1, cb.getCountId()); Rd#R}yA
ps.executeUpdate();⑴ ra$:ibLN
//ps.addBatch();⑵ PJ.\)oP
} E]@&<TFq
//int [] counts = ps.executeBatch();⑶ c{MoeIG)v@
conn.commit(); (;l@d|g
}catch(Exception e){ #rlgeHG!fs
e.printStackTrace(); v~nKO?{
} finally{ E\[B E<y
try{ b#6S8C+@
if(ps!=null) { *G58t`]r
ps.clearParameters(); ${ {4L?7
ps.close(); f7=MgFi
ps=null; o<Zlm)"%1
} Mn0.!J
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}catch(SQLException e){} 2)f_L|o,m
DBUtils.closeConnection(conn); _?c.m*)A
} VgHO&vU
} 'c35%?]
public long getLast(){ ;I>nA6A
return lastExecuteTime; cJ4My#w
} cJo%j -AM
public void run(){ \O|SPhaIf
long now = System.currentTimeMillis(); 7Jn%XxHq
if ((now - lastExecuteTime) > executeSep) { ]Z!Y*v
//System.out.print("lastExecuteTime:"+lastExecuteTime); #J[g
r_
//System.out.print(" now:"+now+"\n"); C`.YOkpj
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); nrl?<4_
lastExecuteTime=now; ,h*gd^i
executeUpdate(); N*Aw-\Bk
} N<)CG,/w[M
else{ @>8(f#S%
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); 7Nq<
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} V[tebv!
} $C[z]}iOi
} X7*F~LFrj
//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 9Dx~!(
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类写好了,下面是在JSP中如下调用。 u[GZ~L
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<% :aNjh
CountBean cb=new CountBean(); -"[4E0g0
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); v
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CountCache.add(cb); cIU2 qFn[
out.print(CountCache.list.size()+"<br>"); Z<vz%7w
CountControl c=new CountControl(); A0{xt*g
c.run(); t!?`2Z5
out.print(CountCache.list.size()+"<br>"); !l'nX
%>