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: W O|2x0K
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CountBean.java ?G0=\U<
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/* A;Xn#t ,(K
* CountData.java p&:RSO
* `Qaw]&O
* Created on 2007年1月1日, 下午4:44 'WxcA)z0cQ
* l_ >^LFOA
* To change this template, choose Tools | Options and locate the template under Le|Ho^h,Y
* the Source Creation and Management node. Right-click the template and choose .QRQvtd.
* Open. You can then make changes to the template in the Source Editor. ran
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*/ (!W:-|[K\
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package com.tot.count; B07(15y]
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/** %I&Hx<Hj
* }yx'U 3
* @author 0K@s_C=n#
*/ TP'EdzAT
public class CountBean { cDm_QYQ
private String countType; ;}=v|Dr&I.
int countId; A4Q8^^byY
/** Creates a new instance of CountData */ **fJAANc
public CountBean() {} 1ncY"S/VO
public void setCountType(String countTypes){ % ]r@vjeyd
this.countType=countTypes; 6$9n_AS
} oizD:|
public void setCountId(int countIds){ )/Ee#)z*
this.countId=countIds; iW.8+?Xq&
} e@NS=U` <
public String getCountType(){ 6b6}HO
return countType; ;W'y^jp]"
} B~jl1g|
public int getCountId(){ l?pZdAE
return countId; ,DXNq`24
} cqRIi~`
} &N[~+"
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CountCache.java -81usu&NH
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/* ;]KGRT
* CountCache.java b H?dyS6Bx
* ~bdADVH
* Created on 2007年1月1日, 下午5:01 Nt$/JBB[$
* #- f7hg*
* To change this template, choose Tools | Options and locate the template under TPvS+_<oL{
* the Source Creation and Management node. Right-click the template and choose =HQH;c"
* Open. You can then make changes to the template in the Source Editor. %_KNAuM
*/ ;ZFn~!V
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package com.tot.count; HZkC3$
import java.util.*; -KCm#!
/** bo0m/hVU
* ;rV0
* @author
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*/ tceQn
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public class CountCache { 5m=3{lBi
public static LinkedList list=new LinkedList(); *&% kkbA
/** Creates a new instance of CountCache */ :PY~Cws
public CountCache() {} qyP@[8eH
public static void add(CountBean cb){ TStu)6%`
if(cb!=null){ R`:Y&)c_$
list.add(cb); ]uWx<aDB
} 6wqq"6w
} r*p<7
} &t+03c8g!
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CountControl.java * G.6\
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/* *jCXH<?R
* CountThread.java (TVzYm
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* rgRh ySud
* Created on 2007年1月1日, 下午4:57 A+iQH1C0h
* eeoIf4]
* To change this template, choose Tools | Options and locate the template under V`l.F"<L
* the Source Creation and Management node. Right-click the template and choose v,KH2 (N
* Open. You can then make changes to the template in the Source Editor. M9fAv
*/ rPv+eM">
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package com.tot.count; 4IG'Tm
import tot.db.DBUtils; <DvpqlT
import java.sql.*; <q~&g
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/** )67Kd]
* uV#/Lgw{M
* @author 8]YFlW9
*/ 7M<7^)9
public class CountControl{ di
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private static long lastExecuteTime=0;//上次更新时间 : N> 5{
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 V+nqQ~pJ&
/** Creates a new instance of CountThread */ :05>~bn>pC
public CountControl() {} k10dkBoEX
public synchronized void executeUpdate(){ pV=X
Connection conn=null; s4@AK48
PreparedStatement ps=null; :\4?{,@_h
try{ 7 1z$a
conn = DBUtils.getConnection(); zEl@jK,{$
conn.setAutoCommit(false); (=j]fnH?
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); !BIq>pO%Ui
for(int i=0;i<CountCache.list.size();i++){ F7E# x
CountBean cb=(CountBean)CountCache.list.getFirst(); so9h6K{qcp
CountCache.list.removeFirst(); W&;X+XA_W
ps.setInt(1, cb.getCountId()); S_y!4;]ox
ps.executeUpdate();⑴ 5$`i)}:s
//ps.addBatch();⑵ #6 e
} `|8)A)ZVT
//int [] counts = ps.executeBatch();⑶ G;Q)A$-
conn.commit(); 9} :n
}catch(Exception e){ zF>|
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e.printStackTrace(); $"!"=v%B
} finally{ *S~gF/*kP
try{ W=M]1hy
if(ps!=null) { h:Q*T*py
ps.clearParameters(); 1Yo9Wf;vP
ps.close(); eRWTuIV6
ps=null; Zoh2m`6
} Be68 Fu0
}catch(SQLException e){} J-:\^uP
DBUtils.closeConnection(conn); ReE6h\j
} Q$iYhR
} |O%`-2p]p
public long getLast(){ </>;PnzE
return lastExecuteTime; V&-pgxf;
} l`:M/z6"
public void run(){ "]f0wLzh
long now = System.currentTimeMillis(); ?dl7!I@<E<
if ((now - lastExecuteTime) > executeSep) { iN %kF'&9
//System.out.print("lastExecuteTime:"+lastExecuteTime); qSlC@@.>
//System.out.print(" now:"+now+"\n"); HpiP"Sl
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); C:"Al-
lastExecuteTime=now; P5yS`v$@
executeUpdate(); <T>C}DGw
} 7H:1c=U
else{ I0h/x5
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); XkHO =
} oP$NTy[
} uLD%M av
} U]riBlg>
//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 T$U,rOB"
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类写好了,下面是在JSP中如下调用。 wN-3@
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<% gI~Ru8
CountBean cb=new CountBean(); (|(#~o]40t
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); G1K5J`"*
CountCache.add(cb); iq)4/3"6
out.print(CountCache.list.size()+"<br>"); #eD@sEn
CountControl c=new CountControl(); Ob$|IH8.
c.run(); ng(STvSh:
out.print(CountCache.list.size()+"<br>"); (]n^_G#-$
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