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: Yxi.A$g
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CountBean.java : @YZ6?hf
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/* #(XP=PUj
* CountData.java 3MkF
* =o+t_.)N
* Created on 2007年1月1日, 下午4:44 Lqwc:%Y:_
* g($ y4~#
* To change this template, choose Tools | Options and locate the template under Qv']*C[!z
* the Source Creation and Management node. Right-click the template and choose nA%-<
* Open. You can then make changes to the template in the Source Editor. P]!eM(
*/ L;grH5K5
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package com.tot.count; ZTHrjW1
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/** 1/j}VC
* w[]7{D];
* @author CX\#
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*/ $yc&f(Tv
public class CountBean { qItj`F)d
private String countType; lD 9'^J
int countId; vgsu~(L;
/** Creates a new instance of CountData */ .VWH
public CountBean() {} >&BgF*mm
public void setCountType(String countTypes){ %
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this.countType=countTypes; "64pVaT4
} u3ce\
public void setCountId(int countIds){ X8?|5$Ey
this.countId=countIds; W99Fb+$I
} 0'aZ*ozk
public String getCountType(){ j3A+:KDn3n
return countType; [,G]#<G?q
} q$U;\Mg)
public int getCountId(){ 6t*=.b,N
return countId; fZXd<Fg+
} DF9Br
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} !"p,9
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CountCache.java sveFxI
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/* *>Om3[D
* CountCache.java 7|"11^q
* Q7`zrCh
* Created on 2007年1月1日, 下午5:01 ,>"1'i&@
* N[zI@>x
* To change this template, choose Tools | Options and locate the template under S.M< (
* the Source Creation and Management node. Right-click the template and choose A5
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* Open. You can then make changes to the template in the Source Editor. =XudL^GF
*/ )e]:T4*vo
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package com.tot.count; F'|,(P
import java.util.*; 7.akp
/** %Sxy!gGz%%
* =a7m^e7
* @author $?I^Dk
*/ 0.&gm@A~c$
public class CountCache { )pJ}o&J
public static LinkedList list=new LinkedList(); VJuPC
/** Creates a new instance of CountCache */ H+_oK
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public CountCache() {} bncK8SK
public static void add(CountBean cb){ }{E//o:Ta
if(cb!=null){ 9-p d{Z~l
list.add(cb);
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} ?mgr#UN
} !YAkHrF`[0
} OM2|c}]ZQ
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CountControl.java OJkPlDym
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/* ChGwG.-%L
* CountThread.java h-!(O^M
* eYR/kZ%<
* Created on 2007年1月1日, 下午4:57 ZOS{F_2.
* 5p"*nkF
* To change this template, choose Tools | Options and locate the template under b*.)m
* the Source Creation and Management node. Right-click the template and choose 2Uu,Vv
* Open. You can then make changes to the template in the Source Editor. TvM{ QGN
*/ VwtGHF'
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package com.tot.count; t}NxD`8
import tot.db.DBUtils; r]8tl
import java.sql.*; |(y6O5Y.
/** L\hPw{)
* `1pri0!
* @author )?Jj#HtW
*/ y]cx}9~
public class CountControl{ VVCCPK^<
private static long lastExecuteTime=0;//上次更新时间 zIRa%%.i<
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 MQR2UK(
/** Creates a new instance of CountThread */ VAq(
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public CountControl() {} F
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public synchronized void executeUpdate(){ `b9oH^}n j
Connection conn=null; 0Dh a1[=
PreparedStatement ps=null; ?V*>4A
try{ MV=.(Zs
conn = DBUtils.getConnection(); 5dYIL`
conn.setAutoCommit(false); u%ih7v!r\
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); <&W3\/xx
for(int i=0;i<CountCache.list.size();i++){ S2j7(T;~YB
CountBean cb=(CountBean)CountCache.list.getFirst(); 0r+-}5aSl5
CountCache.list.removeFirst(); d7KeJ$xy}p
ps.setInt(1, cb.getCountId()); MQ,$'Y5~H
ps.executeUpdate();⑴ b/ZX}<s(1=
//ps.addBatch();⑵ :(I)+;M}P
} @JN%P}4)
//int [] counts = ps.executeBatch();⑶ _k6N(c2Nd
conn.commit(); 4Ag+
}catch(Exception e){ 7B7I'{d
e.printStackTrace(); Gg,,qJO
} finally{ zhYE#hv2
try{ ojyG|Y
if(ps!=null) { %!YsSk,
ps.clearParameters(); ocL
ps.close(); Z< uwqA
ps=null; Rs<,kMRGVL
} ?A2EuvQH]
}catch(SQLException e){} S :(1=@
DBUtils.closeConnection(conn); qJISB7F[%O
} ^Ko0zz|R/
} %}$6#5"';
public long getLast(){ |fRajuA;
return lastExecuteTime; )xTp7YnZ;
} Vvv
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public void run(){ }8x[
long now = System.currentTimeMillis(); A$1pMG~as
if ((now - lastExecuteTime) > executeSep) { Y]P
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//System.out.print("lastExecuteTime:"+lastExecuteTime); y>wr $
//System.out.print(" now:"+now+"\n"); sU+~#K$b
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); s,`
n=#
lastExecuteTime=now; +{Q\B}3cj1
executeUpdate(); i<%(Z[9Lk
} . dM 0
else{ /a9+R)Al
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); zRf]SZ(tO
} 14zo0ANM
} .l#Pmd!
} r2U2pAy#
//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 ?:H9xJ_^
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类写好了,下面是在JSP中如下调用。 Snh\Fgdz
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<% i37W^9 R
CountBean cb=new CountBean(); !pDS*{)E
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); D0"+E*
CountCache.add(cb); CsuSg*#X+
out.print(CountCache.list.size()+"<br>"); H<1C5-
CountControl c=new CountControl(); :()4eK/\
c.run(); wBeOMA
out.print(CountCache.list.size()+"<br>"); &dOV0y_
%>