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: A6?!BB=]
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CountBean.java U.GRN)fL4
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/* SSAf<44e
* CountData.java hr/H vB
* 0|}]=XN^
* Created on 2007年1月1日, 下午4:44 W"v"mjYud
* z@8W
* To change this template, choose Tools | Options and locate the template under /$U<S"
* the Source Creation and Management node. Right-click the template and choose W=S<DtG2
* Open. You can then make changes to the template in the Source Editor. @2`$ XWD
*/ !U"?vS l
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package com.tot.count; 1iJa j
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/** /Xm4%~b_gj
* MS~+P'
* @author (M-Wea!q
*/ ln2lFfz
public class CountBean { M%z$yU`ac
private String countType; qRcY(mb
int countId; $<s;YhM:u)
/** Creates a new instance of CountData */ JQ%D6b
public CountBean() {} 7C>5XyyJ
public void setCountType(String countTypes){ ~-tKMc).X
this.countType=countTypes; lDX\"Fq
} _/5#A+ ?
public void setCountId(int countIds){ a/{M2
this.countId=countIds; VR XK/dZ
} |[W7&@hF
public String getCountType(){ ccY! OSae
return countType; :Ldx^UO
} :pCv!g2
public int getCountId(){ P#l"`C
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return countId; k^#+Wma7
} 6%B)
} #/0d
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CountCache.java KK';ho,W
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/* UbEK2&q/8
* CountCache.java }pJLK\
* asZ(Hz%
* Created on 2007年1月1日, 下午5:01 vACJE
* \(&UDG$
* To change this template, choose Tools | Options and locate the template under :[J'B4>9
* the Source Creation and Management node. Right-click the template and choose mv{bX|.
* Open. You can then make changes to the template in the Source Editor. G -V~6
*/ [:(hqi!
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package com.tot.count; E0)43
import java.util.*; D$U`u[qjtS
/** xl ]1TB@
* 61W[
* @author ^N&@7s
*/ @h,3"2W{Ev
public class CountCache { WD >z
public static LinkedList list=new LinkedList(); dvu8V_U
/** Creates a new instance of CountCache */ \ RS
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public CountCache() {} t`")Re_j
public static void add(CountBean cb){ eXAJ%^iD
if(cb!=null){ Q#5~"C
list.add(cb); ;J,`v5z0:
} \h@3dJ4
} awl3|k/
} tUk)S
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CountControl.java dT7!+)s5-
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/* 3_ ZlZ_Tq
* CountThread.java 2C AR2V|
* .$ X|96~$
* Created on 2007年1月1日, 下午4:57 FEA t6
* }u]7 x:lh
* To change this template, choose Tools | Options and locate the template under lSG]{
* the Source Creation and Management node. Right-click the template and choose a];1)zVA6
* Open. You can then make changes to the template in the Source Editor. Ku?1QDhrF*
*/ rcz9\@M
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package com.tot.count; slQEAqG)B
import tot.db.DBUtils; UuCRQN H
import java.sql.*; -sxu7I
/** ^Rb*mI
* dK41NLGQ
* @author /RI"a^&9A
*/ "i,ZG$S#E
public class CountControl{ ZkryoIQ%=
private static long lastExecuteTime=0;//上次更新时间 n.=Zw2FE
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 ]oLyvG
/** Creates a new instance of CountThread */ uvl>Z=
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public CountControl() {} 2j&0U!DX
public synchronized void executeUpdate(){ 6xLQ
Connection conn=null; wpg7xx!
PreparedStatement ps=null; O t{~mMDp
try{ }`y%*--
conn = DBUtils.getConnection(); <DN7
conn.setAutoCommit(false); gKP=@v%-
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); 8GeJ%^0o}
for(int i=0;i<CountCache.list.size();i++){ FE dFGT
CountBean cb=(CountBean)CountCache.list.getFirst(); yRR[M@Y
CountCache.list.removeFirst(); 9v/=o`J#
ps.setInt(1, cb.getCountId()); 'fYF1gR4
ps.executeUpdate();⑴ #$;}-*
//ps.addBatch();⑵ _%u t#
} Pq,iR J
//int [] counts = ps.executeBatch();⑶ ~? :>=x
conn.commit();
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}catch(Exception e){ =~TPrO^
e.printStackTrace(); W[:CCCDL
} finally{ `<-/e%8
try{ uann'ho?q
if(ps!=null) { s6k(K>Pl
ps.clearParameters(); L=dQ,yA
ps.close(); ^<3{0g-"AW
ps=null; 2B"tT"f
} *j<{3$6Ii
}catch(SQLException e){} ?}U?Q7vx@@
DBUtils.closeConnection(conn); w:ASB>,!
} _UV_n!R
} O1!YHo
public long getLast(){ n&2OfBJ
return lastExecuteTime; W5/|.}
} sB5@6[VDI
public void run(){ F!g;}_s9
long now = System.currentTimeMillis(); Q <ulh s
if ((now - lastExecuteTime) > executeSep) { ZK h4:D
//System.out.print("lastExecuteTime:"+lastExecuteTime); qJE_4/<^!
//System.out.print(" now:"+now+"\n"); Sx1|Oq]
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); [ldBI3
lastExecuteTime=now; "m`}J*s"
executeUpdate(); X\kWJQ:
} 2BiFP||
else{ (+SL1O P
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); :j? MEeu
} 6xFchdMG{m
} Dutc#?bT
} PZVH=dagq
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 B`YD>oCN
CwD=nT5`
类写好了,下面是在JSP中如下调用。 Vjd(Z
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<% 9&{z?*
CountBean cb=new CountBean(); Vha,rIi
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); )q`.tsR>
CountCache.add(cb); w3#0kl
out.print(CountCache.list.size()+"<br>"); 0\Tp/Ph
CountControl c=new CountControl(); bB)$=7\
c.run(); >7r%k,`
out.print(CountCache.list.size()+"<br>"); #/5eQTBD
%>