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: N0K>lL=
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CountBean.java +Y5(hjE
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/* t(j_eq}J
* CountData.java ,a9D~i 9R
* *dG}R#9Nv
* Created on 2007年1月1日, 下午4:44 FYXw$7'l
* T\2) $
* To change this template, choose Tools | Options and locate the template under YHO;IQ5
* the Source Creation and Management node. Right-click the template and choose +U+aWk
* Open. You can then make changes to the template in the Source Editor. j(Fa=pi
*/ L_Y9+
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package com.tot.count; D%;wVnUw
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/** A#Q0{z@H
* Ox7uG{t$#
* @author SaR}\Up
*/ '0CXHjZN
public class CountBean { L,b|Iq
private String countType; Ws^+7u
int countId; RRS~ xOg
/** Creates a new instance of CountData */ %\X P:
public CountBean() {} !cN?SGafZI
public void setCountType(String countTypes){ ;Na8_}
this.countType=countTypes; k1f3?l
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} S_T{L
public void setCountId(int countIds){ $ DDSN
this.countId=countIds; } g3HoFC
} /FP ~jV!z
public String getCountType(){ d7W%zg\T
return countType; (XbMrPKG
} aQ!9#d_D
public int getCountId(){ C3
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return countId; B@cJ\
} iO%Zd[
} G *mO&:q
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CountCache.java b?Cmc
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/* 0NL :z1N-h
* CountCache.java >vD['XN,
* E6'8Zb
* Created on 2007年1月1日, 下午5:01 3AdP^B<
* x1 ;rb8
* To change this template, choose Tools | Options and locate the template under &5kZ{,-eM
* the Source Creation and Management node. Right-click the template and choose @9_nwf~X4
* Open. You can then make changes to the template in the Source Editor. q4sl=`L5Sp
*/ lSn5=^]q
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package com.tot.count; lq>*x=<
import java.util.*; eZ@Gu
/** 9nng}em>.
* @DfkGm[%
* @author vQ:x%=]
*/ S}zC3
public class CountCache { 8lU;y)Z
public static LinkedList list=new LinkedList(); -d|BO[4j
/** Creates a new instance of CountCache */ 5wzQ?07T_
public CountCache() {} Hi]vHG(
public static void add(CountBean cb){ ojN`#%X
if(cb!=null){ ?@Z7O.u
list.add(cb); <KHv|)ak
} #'J~Xk
} Qy{NS.T
} wD<vg3e[H
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CountControl.java 5"1!p3`\D{
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/* CCuxC9i7
* CountThread.java Rz`@N`U
* v\fzO#vj
* Created on 2007年1月1日, 下午4:57 gXq!a|eH
* /lf\
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* To change this template, choose Tools | Options and locate the template under "%:7j!#X|I
* the Source Creation and Management node. Right-click the template and choose E=;BI">.
* Open. You can then make changes to the template in the Source Editor. Xy[}G p
*/ Z -pyFK\
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package com.tot.count; tegOT]|
import tot.db.DBUtils; c *.G]nRc
import java.sql.*; D",A$(lG
/** Q8 -3RgAw
* D8k*0ei&
* @author =Ml|l$
*/ a;56k
public class CountControl{ uAp
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private static long lastExecuteTime=0;//上次更新时间 x
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private static long executeSep=60000;//定义更新间隔时间,单位毫秒 M{*kB2jr
/** Creates a new instance of CountThread */ &@=u+)^-{
public CountControl() {} `ajx hp
public synchronized void executeUpdate(){ h^['rmd
Connection conn=null; ;rNd701p"
PreparedStatement ps=null; `!zQ
try{ "w;08TX8
conn = DBUtils.getConnection(); M_tj7Q3
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conn.setAutoCommit(false); vAi"$e
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); vz6SCGg,
for(int i=0;i<CountCache.list.size();i++){ JR/W9i
CountBean cb=(CountBean)CountCache.list.getFirst(); ktN%!Mh\
CountCache.list.removeFirst(); kclp}
ps.setInt(1, cb.getCountId()); XlRw Z/Wc
ps.executeUpdate();⑴ W7%p^;ZQ$
//ps.addBatch();⑵ zs4>/9O
} P`}$-#D F
//int [] counts = ps.executeBatch();⑶ u06tDJ[
conn.commit(); xy2\'kS`G
}catch(Exception e){ {V.Wk
e.printStackTrace(); Z/xV\Ggx
} finally{ /CIx$G
try{ SrSG{/{
if(ps!=null) { y= 2=DU
ps.clearParameters(); 5RW@_%C
ps.close(); NI^{$QMj
ps=null; b([:,T7
} y^9bfMA
}catch(SQLException e){} I9;xz ES
DBUtils.closeConnection(conn); >g=^,G}y
} TKK,Y{{
} 1d`cTaQ-
public long getLast(){ K-Re"zsz
return lastExecuteTime; 8098y,mQe
} bi+9R-=&
public void run(){ KCE=|*6::|
long now = System.currentTimeMillis(); 5n:nZ_D
if ((now - lastExecuteTime) > executeSep) { !zU/Hq{wcK
//System.out.print("lastExecuteTime:"+lastExecuteTime); xf'LR[M
//System.out.print(" now:"+now+"\n"); miwf&b
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); 9p5= _
lastExecuteTime=now; yGRR8F5>(
executeUpdate(); M/*Bh,M`
}
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else{ (m6EQoW^s+
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); ^#2xQ5h
} Umij!=GPG^
} nZ~kZ |VS
} </,.K`''W
//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 cxgE\4_u"
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类写好了,下面是在JSP中如下调用。
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<% 'gYg~=
CountBean cb=new CountBean(); z23#G>I&
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); 46ILs1T6
CountCache.add(cb); ;"D~W#0-v
out.print(CountCache.list.size()+"<br>"); >8%M*-=p
CountControl c=new CountControl(); Ha?G=X
c.run(); lHcA j{6
out.print(CountCache.list.size()+"<br>"); C(}^fJ6r
%>