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: lsB9;I^+x
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CountBean.java j
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/* XYb^Cs;
* CountData.java G !1~i*P$u
* 1qLl^DW
* Created on 2007年1月1日, 下午4:44 KM/U?`6>:
* A{aw<
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* To change this template, choose Tools | Options and locate the template under aVppOxA
* the Source Creation and Management node. Right-click the template and choose |k`f/*
* Open. You can then make changes to the template in the Source Editor. Q&Z4r9+Z
*/ bB:r]*_
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package com.tot.count; :WK"-v
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/** ePq13!FC/
* g|K6iY
* @author `dv}a-Q)c
*/ fO^e+Mz
public class CountBean { >bfYy=/
private String countType; $hjP}- oUX
int countId; MX!u$ei
/** Creates a new instance of CountData */ %XP_\lu]
public CountBean() {} k_D4'(V:b
public void setCountType(String countTypes){ t."g\;
this.countType=countTypes;
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}
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public void setCountId(int countIds){ gppBFS
this.countId=countIds; 1B)Y;hg6&
} 9VoDhsKk
public String getCountType(){ 8K\'Z
return countType; NP K#].F
} +}_Pf{MW
public int getCountId(){ kmm
return countId; 4S,. R
} ?HrK\f3wWO
} _ PXG AS
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CountCache.java aO8ch
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/* Guk.,}9
* CountCache.java )Y3EQxXa
* L([E98fo
* Created on 2007年1月1日, 下午5:01 I
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* tHrK~|
* To change this template, choose Tools | Options and locate the template under WnD^F>
* the Source Creation and Management node. Right-click the template and choose ecr886
* Open. You can then make changes to the template in the Source Editor. A2m_q>>
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*/ G9DJa_]X
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package com.tot.count; duX0Mc.0P
import java.util.*; e8$l0gzaD
/** ;mEwQ
* MaZM%W8Z
* @author
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*/ gRBSt
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public class CountCache { a%Uw;6|{
public static LinkedList list=new LinkedList(); l B1#
/** Creates a new instance of CountCache */ HbcOTd)=5
public CountCache() {} sU\c#|BSC"
public static void add(CountBean cb){ {vs 4vS6
if(cb!=null){ rkkU"l$v
list.add(cb); $tI]rU
} j5PL{6
} !RS9%ES_?
} [+;qWfs B
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CountControl.java X*i/A<Y`=
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/* ?AEd(_a!q
* CountThread.java
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* :M06 ;:e
* Created on 2007年1月1日, 下午4:57 }^9]jSq5
* 2K;#Evn'j
* To change this template, choose Tools | Options and locate the template under 0o;O`/x
* the Source Creation and Management node. Right-click the template and choose F!JJ6d53y
* Open. You can then make changes to the template in the Source Editor. :-?Ct
*/ @:Di`B_{
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package com.tot.count; Br}h/!NU/
import tot.db.DBUtils; EFAGP${F
import java.sql.*; XAPYpBgm
/** 1"}cdq.
* qos`!=g?
* @author
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*/ $J.T$0pFa
public class CountControl{ sc W'AJJq
private static long lastExecuteTime=0;//上次更新时间 h>alGLN>
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 YzAFC11,
/** Creates a new instance of CountThread */ XF|WCZUnY%
public CountControl() {} q_ %cbAcD
public synchronized void executeUpdate(){ mffIf1f
Connection conn=null; YD\]{,F|
PreparedStatement ps=null; C)Jn[/BD
try{ Tv5g`/e=Ej
conn = DBUtils.getConnection(); GMW,*if8p
conn.setAutoCommit(false); MAqLIf<G
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); :~zv t
for(int i=0;i<CountCache.list.size();i++){ w%dL8k
CountBean cb=(CountBean)CountCache.list.getFirst(); jTb-;4N'
CountCache.list.removeFirst(); B@O@1?c[
ps.setInt(1, cb.getCountId()); N8v'70
ps.executeUpdate();⑴ 2 -Xdoxw
//ps.addBatch();⑵ f?56=& pHY
} zP!J/}z
//int [] counts = ps.executeBatch();⑶ x0Yse:RE^
conn.commit(); {f/ ]5x(_
}catch(Exception e){ v>A=2i*j
e.printStackTrace(); f[sF:f(zI
} finally{ 9!U@"~yB
try{ \*0yaSQF
if(ps!=null) { !:CJPM6j3
ps.clearParameters(); nmFC%p)4
ps.close(); pFsc}R/0/8
ps=null; (\a6H2z8l
} !}KqB8;
}catch(SQLException e){} w$|l{VI
DBUtils.closeConnection(conn); o.-C|IXG
} ]3Dl)[R
} q
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public long getLast(){ x;\wY'
return lastExecuteTime; fP HLXg5s
} ;WU<CKYG*
public void run(){ `^9(Ot $
long now = System.currentTimeMillis(); ?BA^YF
if ((now - lastExecuteTime) > executeSep) { bEV<iZDq%
//System.out.print("lastExecuteTime:"+lastExecuteTime); ^Q+i=y{W
//System.out.print(" now:"+now+"\n"); N_Akmh0D
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); ? 1*m,;Z
lastExecuteTime=now; $gpG%Qj
executeUpdate(); _7T@5\b:;
} P
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else{ x]|+\1
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); l8h&|RY[
} 6\jf|:h
} mTNVU@TY=
} {yA$V0`N{
//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 f.B>&%JRZ
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类写好了,下面是在JSP中如下调用。 5kNzv~4B,;
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<%
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CountBean cb=new CountBean(); $_H`
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); h].~# *
CountCache.add(cb); s@hRqGd:
out.print(CountCache.list.size()+"<br>"); G rmzkNlN
CountControl c=new CountControl(); :!a2]-D}
c.run(); E m
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out.print(CountCache.list.size()+"<br>"); `+:.L>5([
%>