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: (J&Xo.<Z-
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CountBean.java ^-u HdafP
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/* prN(V1O
* CountData.java 0 '7s
* zD^f%p ["#
* Created on 2007年1月1日, 下午4:44 e:LZ s0
* 2^6TrZA7M6
* To change this template, choose Tools | Options and locate the template under /K) b0QX
* the Source Creation and Management node. Right-click the template and choose k6'#
* Open. You can then make changes to the template in the Source Editor. tR*W-%
*/ _]UDmn[C
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package com.tot.count; ;j U-<
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/** df6Ν4L
* xzl4v=7
* @author I~LQ1_
*/ F/*fQAa"
public class CountBean { }Tr83B|
private String countType; x7Rq|NQ
int countId; s2?,' es
/** Creates a new instance of CountData */ `B\KS*Gya#
public CountBean() {} R+K&<Rz
public void setCountType(String countTypes){ x}<G!*3
this.countType=countTypes; o:8S$F`O@
} xdfvme[
public void setCountId(int countIds){ l5';?>!s
this.countId=countIds; #A/J^Ko
} tH,K\v`f
public String getCountType(){ ~,!hE&LE~
return countType; yp{F8V 8
} UD<^r]'x
public int getCountId(){ v?D
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return countId; W(a'^
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} ZqbM%(=z(`
} 1mn$Rh&dO
C}=_8N
CountCache.java h2|vB+W-
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/* '%-xe3
* CountCache.java ;Nf hKu%K
* 7lDaok
* Created on 2007年1月1日, 下午5:01 )SL@>Cij
* ~|Ih
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* To change this template, choose Tools | Options and locate the template under "aWX:WL&}s
* the Source Creation and Management node. Right-click the template and choose ONN{4&7@<
* Open. You can then make changes to the template in the Source Editor. |g\. 5IM#W
*/ #~URLN
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package com.tot.count; 9hR:y.
import java.util.*; K~Au?\{
/** r,.95@
* J;=aIiN]R
* @author ?X_0Iy}1
*/ )_b@~fC
public class CountCache { '5xuT _
public static LinkedList list=new LinkedList(); Ec*--]j*c
/** Creates a new instance of CountCache */ $qlqWy-s
public CountCache() {} p=-B~:
public static void add(CountBean cb){ F*4Qa
if(cb!=null){ bpF@}#fT
list.add(cb); |T$a+lHMD
} eW"x%|/Q7
} D;^ZWz0
} vQBY1-S
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CountControl.java Ife,h
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/* ?mYV\kDt\
* CountThread.java j |'#5H`
* @%G' U&R{
* Created on 2007年1月1日, 下午4:57 D2TXOPH
* SJ@8[n.x
* To change this template, choose Tools | Options and locate the template under yToT7 X7F7
* the Source Creation and Management node. Right-click the template and choose Xw*%3'
* Open. You can then make changes to the template in the Source Editor. ;ad9{":J#B
*/ 4('0f:9z+
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package com.tot.count; .}$`+h8WT
import tot.db.DBUtils; Y1yXB).AH8
import java.sql.*; f^6&Fb>
/** g`)/ x\
* igRDt{}
* @author ^i`3cCFB<
*/ E2q B:
public class CountControl{ z6FbM^;;
private static long lastExecuteTime=0;//上次更新时间 Pa+AF
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 #"o6OEy$A#
/** Creates a new instance of CountThread */ f
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public CountControl() {} Gh$y#0qr
public synchronized void executeUpdate(){ [L*[j.r7[
Connection conn=null; %qNj{<&
PreparedStatement ps=null; 5&n988gC8
try{ NWQPOq#
conn = DBUtils.getConnection(); p-T~x$"c|
conn.setAutoCommit(false); m0BG9~p|
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); %/tGkS6
for(int i=0;i<CountCache.list.size();i++){ w>z8c3Dq}
CountBean cb=(CountBean)CountCache.list.getFirst(); x;ERRK
CountCache.list.removeFirst(); $vg moJ@X0
ps.setInt(1, cb.getCountId()); 5S|}:~7T
ps.executeUpdate();⑴ (b`4&sQ<
//ps.addBatch();⑵ |i}+t
} \]f5
//int [] counts = ps.executeBatch();⑶ mJGO)u&
conn.commit(); V(lK`dY
}catch(Exception e){ GG@I!2,_
e.printStackTrace(); YoV^xl6g
} finally{ t3
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try{ e-%7F]e
if(ps!=null) { ;Xfd1
ps.clearParameters(); SmT+L,:D
ps.close(); o7c%\v[
ps=null; @H3 s2|
} _q$0lqq~u
}catch(SQLException e){} %2@ Tj}xa
DBUtils.closeConnection(conn); |z!q
r}i
} dt-Qu},8-
} 0^<Skm27"
public long getLast(){ ~!3t8Hx6
return lastExecuteTime; [0% yJH
} NSMjr_
public void run(){ @b::6n/u
long now = System.currentTimeMillis(); OQytgXED
if ((now - lastExecuteTime) > executeSep) { Edf=?K+\!i
//System.out.print("lastExecuteTime:"+lastExecuteTime); g33<qYxP
//System.out.print(" now:"+now+"\n"); XI%RneuDr:
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); +X* F<6mZ
lastExecuteTime=now; ' D)1ka.
executeUpdate(); K)Df}fVOc
} CU#L *kz
else{ eHVdZ'%x
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); r!=]Q}`F
} ;1{iF2jZ:
} %Lh-aP{[e
} wE,=%?"
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 I<D&,LFH*w
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类写好了,下面是在JSP中如下调用。 vKU]80T
dp"<KcP_
<% ]97Xu_
CountBean cb=new CountBean(); .iOw0z
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); i63`B+L{
CountCache.add(cb); 9_J!s
out.print(CountCache.list.size()+"<br>"); N<L$gw+)$D
CountControl c=new CountControl(); c*S#UD+
c.run(); 5}-)vsa`
out.print(CountCache.list.size()+"<br>"); `YFkY^T
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