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: ;1(qGy4
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CountBean.java XH_qA[=c]
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/* +wPvQKVfI
* CountData.java +@<^i?ale
* 37za^n?SG
* Created on 2007年1月1日, 下午4:44 ni 02N3R
* lzQ&)7`
* To change this template, choose Tools | Options and locate the template under f R{WS:Pv
* the Source Creation and Management node. Right-click the template and choose MZhJ,km)
* Open. You can then make changes to the template in the Source Editor. * Kp ^al
*/ <T=o]M$
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package com.tot.count; B=nx8s
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/** #!F8n` C-
* 'KN!m|
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* @author Xf'
*/ M#22Zfxq
public class CountBean { @?($j)9}
private String countType; )Lv6vnT>
int countId; ~jrU#<'G9
/** Creates a new instance of CountData */ y|2g"J
public CountBean() {} iR4,$Nn>
public void setCountType(String countTypes){ 8mQd*GGu1
this.countType=countTypes; m SvTnd8
} E Zu
public void setCountId(int countIds){ "}azC|:5
this.countId=countIds; ::Ve ,-0
} n$\6}\k
public String getCountType(){
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return countType; B1AF4}~5
} RAXJsF^5o
public int getCountId(){ {3yws4
return countId; RWEgUDX^/
} :fMM-?s]
} W0C$*oe!_i
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CountCache.java &opH\wa
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/* uma9yIk
* CountCache.java ~NJL S-
* hJtghG6v
* Created on 2007年1月1日, 下午5:01 epm8N /
* l.t. ,:
* To change this template, choose Tools | Options and locate the template under 5Qe}v
* the Source Creation and Management node. Right-click the template and choose Y_ u7
0@`
* Open. You can then make changes to the template in the Source Editor. ?\ i,JJO
*/ 39^uLob
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package com.tot.count; xdSj+507
import java.util.*; J5r
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/** {gq:sj>
* N6 Cc%,
* @author m]b.P,~v
*/ +r34\mAO
public class CountCache { i_Q4bhVj
public static LinkedList list=new LinkedList(); Z_TbM^N
/** Creates a new instance of CountCache */ @eD2<e
public CountCache() {} W71#NjM2Z
public static void add(CountBean cb){ ;R-Q,aCM}
if(cb!=null){ 8CHf. SXh
list.add(cb); 'J<zVD}0
} |@uhq>&
} Hwi7oXP
} Wn)A/Z ^r
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CountControl.java N_~Wu
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/* vmQ
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* CountThread.java Ymh2qGcj]8
* E!]rh,mYK
* Created on 2007年1月1日, 下午4:57 :j!_XMyT:
* [AK %~Kg9
* To change this template, choose Tools | Options and locate the template under {s^n|b}
* the Source Creation and Management node. Right-click the template and choose So0,)
* Open. You can then make changes to the template in the Source Editor. ;jfXU_K
*/ oI"Fpo
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package com.tot.count; t`/RcAwA
import tot.db.DBUtils; GVPEene
import java.sql.*; fxCPGj
/** 5EZr"[8M
* I2!&=" 7@
* @author pPqbD}p
*/ tw^.(m5d
public class CountControl{ A-NC,3
private static long lastExecuteTime=0;//上次更新时间 )e$-B]>7z
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 ~<Qxw>S#
/** Creates a new instance of CountThread */ bqLYF[#T
public CountControl() {} qQ\hUii
public synchronized void executeUpdate(){ }z%/6`7)|
Connection conn=null; CMB$RLf
PreparedStatement ps=null; hQrsZv:Q
try{ 6j.(l4}
conn = DBUtils.getConnection(); MkIO0&0O
conn.setAutoCommit(false); 2H0q\zZ
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); "VhrsVT
for(int i=0;i<CountCache.list.size();i++){ 9n2%7dLQ*
CountBean cb=(CountBean)CountCache.list.getFirst(); %.}
CountCache.list.removeFirst(); %1l80Z
ps.setInt(1, cb.getCountId()); q+=@kXs>+
ps.executeUpdate();⑴ [ Sa
C
//ps.addBatch();⑵ bSKV|z/x
} M;@03 x W
//int [] counts = ps.executeBatch();⑶ ^C#bW<T
conn.commit(); *fyEw\`a
}catch(Exception e){ dEl3?~
e.printStackTrace(); )HiTYV)]'
} finally{ nWg)zj:
try{ GeR-k9
if(ps!=null) { 9!<3qx/
ps.clearParameters(); :'Kx?Es
ps.close(); mr\L q~*c
ps=null; F973U
} G@6,O-Sj
}catch(SQLException e){} "U~@o4u;
DBUtils.closeConnection(conn); <cd%n-
} C)dYAq3,8
} WUQh[A41
public long getLast(){ n/|`Dz.
return lastExecuteTime; =Qq^=3@h
} ?DTP-#5Ba
public void run(){ h1d0{
long now = System.currentTimeMillis(); B$eF@v"
if ((now - lastExecuteTime) > executeSep) { Al;oI3
//System.out.print("lastExecuteTime:"+lastExecuteTime); H s 3*OhK\
//System.out.print(" now:"+now+"\n"); "!eT
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); v[=E f
lastExecuteTime=now; U-N/Z\QD
executeUpdate(); b-gVRf#F
} 2n,73$s
else{ 833t0Ml1A/
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); "+C\f)
} y^fU_L?p
} *y$r y]
} c7N9X 3A
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 SQ.Wj?W)
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类写好了,下面是在JSP中如下调用。 8xz7S
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<% 69w"$Vk
CountBean cb=new CountBean(); eNskuG|1
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); '%7]xp
CountCache.add(cb); u $^`hzfI
out.print(CountCache.list.size()+"<br>"); BFRSYwPr
CountControl c=new CountControl(); X+BSneu
c.run(); y6yseR!
out.print(CountCache.list.size()+"<br>"); XsMphZnK
%>