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: x*unye7
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CountBean.java h'B9|Cm
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/* s8t f@H4r
* CountData.java 5R,la\!bQ
* h`?y2?O
* Created on 2007年1月1日, 下午4:44 E7rX1YdR
* o-SRSu
* To change this template, choose Tools | Options and locate the template under C!!mOAhJ
* the Source Creation and Management node. Right-click the template and choose T(Y}V[0+
* Open. You can then make changes to the template in the Source Editor. [urH a
*/ )UR1E?'
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package com.tot.count; [zY!'cz?
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/** YO)')&
* Sdgb#?MR|
* @author %S{o5txo
*/ nHSTeFI?
public class CountBean { qPsyqn?Y|
private String countType; d4d\0[
int countId; xe(MHNrj
/** Creates a new instance of CountData */ oz%h)#;
public CountBean() {} ;e&!
public void setCountType(String countTypes){ wX-RQ[2X
this.countType=countTypes; {V[Ha~b%*
} ;US83%*
public void setCountId(int countIds){ 5\VxXiy0
this.countId=countIds; %z1{Kus
} z8b
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public String getCountType(){ pz$_W
return countType; -{!&/;Z
} pAENXC\,
public int getCountId(){ mH'\:oN
return countId; Qn*6D
} G-2EQ.
} v-ThdE$G#
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CountCache.java 6/|U
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/* wOjv[@d
* CountCache.java >[K0=nA
* mDZ=Due1
* Created on 2007年1月1日, 下午5:01 {U(Bfe^a,
* w]n4KR4
* To change this template, choose Tools | Options and locate the template under ]X*YAPv
* the Source Creation and Management node. Right-click the template and choose 9^oo-,Su_
* Open. You can then make changes to the template in the Source Editor. pw!@Q?R
*/ {n\6BTs
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package com.tot.count; ;JYoW{2
import java.util.*; m6-76ma,hi
/** ]+AAT=B<!
* 9KXym }
* @author QS\Uq(Ja\
*/ H]BAW *}
public class CountCache { 60'6/3
public static LinkedList list=new LinkedList(); L5/mO6;k
/** Creates a new instance of CountCache */ s){Q&E~X
public CountCache() {} 7O:"~L
public static void add(CountBean cb){ 5KK{%6#f\
if(cb!=null){ "rVU4F)
list.add(cb); @Eo4U]-
} kr#I{gF
} Cgo9rC~]
} gTnS[
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CountControl.java B0v|{C
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/* FK6K6wU52m
* CountThread.java Z^<Sj5}6
* D
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* Created on 2007年1月1日, 下午4:57 HQl~Dh0DJ
* 2@fa
rx:
* To change this template, choose Tools | Options and locate the template under +1x)z~q=
* the Source Creation and Management node. Right-click the template and choose O5O.><RP
* Open. You can then make changes to the template in the Source Editor. ikr7DBLt
*/ XYts8}y5
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package com.tot.count; {f-XyF1`
import tot.db.DBUtils; `6P?G|'
import java.sql.*; J8J!#j.
/** w3d34*0$
* PzLJ/QER
* @author YN/u9[=`
*/ lO[E[c G
public class CountControl{ q4)Ey
private static long lastExecuteTime=0;//上次更新时间 uNy!<u
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 %w$mSG
/** Creates a new instance of CountThread */ ?;_H{/)m
public CountControl() {} E.9^&E}PG
public synchronized void executeUpdate(){ cg{Gc]'1#
Connection conn=null; of=ql
PreparedStatement ps=null; vffH
try{ Y!M~#oqio
conn = DBUtils.getConnection(); Mo_$b8i
conn.setAutoCommit(false); bTiBmS
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); ZEqE$:
for(int i=0;i<CountCache.list.size();i++){ u7[pLtOwN
CountBean cb=(CountBean)CountCache.list.getFirst(); V;k#})_-
CountCache.list.removeFirst(); l**3%cTb
ps.setInt(1, cb.getCountId()); @*SA$9/l
ps.executeUpdate();⑴ 2Q}7fht
//ps.addBatch();⑵ z#RuwB+
} O~atNrHD
//int [] counts = ps.executeBatch();⑶ 7u|%^Ao6
conn.commit(); *.o"ZVl
}catch(Exception e){ 3+%nn+m
e.printStackTrace(); 5*Btb#:
} finally{ ?T
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try{ p=vV4 C:
if(ps!=null) { 'aZASPn[
ps.clearParameters(); _\UIc;3Gl
ps.close(); l77'Lne
ps=null; @C=m?7O98
} 8A!'I<S1
}catch(SQLException e){} oK$'9c5<
DBUtils.closeConnection(conn); *y?[<2"$
} $C$ub&D
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} js
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public long getLast(){ [<Q4U{F
return lastExecuteTime; }Bi@?Sb
} B>, A(X&
public void run(){ \qB6TiB/
long now = System.currentTimeMillis(); ~@@
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if ((now - lastExecuteTime) > executeSep) { W6i3Psjsw
//System.out.print("lastExecuteTime:"+lastExecuteTime); 2
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//System.out.print(" now:"+now+"\n"); m2Q$+p@
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); i\ "{#
lastExecuteTime=now; EWO /u.z
executeUpdate(); @%:E }
} kf'=%]9#_T
else{ @+E7w6>%
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); >9MS"t
} I3PQdAs~&h
} *x!LKIpv
} &Q~)]|t
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 D?mDG|Z
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类写好了,下面是在JSP中如下调用。 ` .$&T7
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<% dWUUxKC
CountBean cb=new CountBean(); h9jc,Xu5X
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); ?9Ma^C;}
CountCache.add(cb); E>"8/
out.print(CountCache.list.size()+"<br>"); ($'V&x8T
CountControl c=new CountControl(); \FXp*FbQ
c.run(); ~?d>fR:X
out.print(CountCache.list.size()+"<br>"); ;Yv14{T!
%>