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: }V\N16f
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CountBean.java zP<pEI
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/* ZRYEqSm
* CountData.java n'emNRa
* 0V?F'<qy
* Created on 2007年1月1日, 下午4:44 8g7<KKw
* -44l^}_u
* To change this template, choose Tools | Options and locate the template under j)q\9#sI/(
* the Source Creation and Management node. Right-click the template and choose &4_qF^9J
* Open. You can then make changes to the template in the Source Editor. i&n'N8D@
*/ CD8}I85K
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package com.tot.count; 33}oO,}t,
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/** %Rsp;1Z
* Sf8{h|71
* @author G$sA`<<
*/ 71l%MH
public class CountBean { TiH)5
private String countType; b5^OQH{v
int countId; 4ni3kmvX
/** Creates a new instance of CountData */ M+x,opl
public CountBean() {} 0x!2ihf
public void setCountType(String countTypes){ Fgh]KQ/5
this.countType=countTypes; QPq7R
} b6*!ACY
public void setCountId(int countIds){ ]~Z6;
this.countId=countIds; +sJrllrE(
} zen*PeIrA^
public String getCountType(){ [
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return countType; D|.ic!w'
} twx[s$O'b
public int getCountId(){ ?^N3&ukkyo
return countId; GQ-Rtn4v
} =lpQnj"
} @K!&qw
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CountCache.java Y3=_ec3w
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/* 8}(]]ayl
* CountCache.java oqeSG.1
* }C|dyyr
* Created on 2007年1月1日, 下午5:01 :GJ &_YHf
* F,'exuZ
* To change this template, choose Tools | Options and locate the template under M8TSt\
* the Source Creation and Management node. Right-click the template and choose -neKuj
* Open. You can then make changes to the template in the Source Editor. uAWM\?
*/ Zcc9e03
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package com.tot.count; LupkrxV
import java.util.*; :Q@&5!]>d
/** >i6yl5s
* c?@T1h4
* @author OiP!vn}k
*/ n-@j5w+k4
public class CountCache { -xP!"
public static LinkedList list=new LinkedList(); q?ix$nKOv
/** Creates a new instance of CountCache */ NhYLtw^u
public CountCache() {} Q6r7.pk"SU
public static void add(CountBean cb){ Ct%x&m:
if(cb!=null){ G2FXrkU
list.add(cb); J^g!++|2P
} |.3DD"*
} T|6a("RL
} &sd}ulEg`
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CountControl.java W='>:H
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/* n9xAPB }
* CountThread.java 2TA*m{\Hr
* /ID?DtJ
* Created on 2007年1月1日, 下午4:57 x>Jr_A(
* GbaEgA'fa
* To change this template, choose Tools | Options and locate the template under Y"wUt &
* the Source Creation and Management node. Right-click the template and choose j ku}QM^
* Open. You can then make changes to the template in the Source Editor. g"> {9YE
*/ # m *J&
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package com.tot.count; =i7`ek
import tot.db.DBUtils; ziCHjqT
import java.sql.*; ,YMp<C
/** aT$9;
* Xqm::1(-(
* @author .>IhN 5
*/ MHC^8VL
public class CountControl{ _> *jH'
private static long lastExecuteTime=0;//上次更新时间 !U~WK$BP
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 $
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/** Creates a new instance of CountThread */ 4%3Mb-#Y]
public CountControl() {} smDw<slC
public synchronized void executeUpdate(){ ;/rXQe1
Connection conn=null; q+vx_4
PreparedStatement ps=null; qm8&*UuKJ
try{ .?Gd'Lp
conn = DBUtils.getConnection(); jav#f{'
conn.setAutoCommit(false);
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ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); #"5 Dk#@
for(int i=0;i<CountCache.list.size();i++){ aqc?pqM
CountBean cb=(CountBean)CountCache.list.getFirst(); v3jg~"!
CountCache.list.removeFirst(); $"H{4x`-
ps.setInt(1, cb.getCountId()); E 0?iXSJ
ps.executeUpdate();⑴ 6ZQwBS0Y
//ps.addBatch();⑵ Q(oN/y3,
} 7[}xP#Z
//int [] counts = ps.executeBatch();⑶ KPj\-g'A
conn.commit(); L#
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}catch(Exception e){ 7fba-7-P
e.printStackTrace(); w2'f/
} finally{ pn5Q5xc
try{ K]0JC/R6(@
if(ps!=null) { `u&Zrdr,
ps.clearParameters(); gjAIEI
ps.close(); ixT:)|'i
ps=null; B,=H@[Fj
} Uh):b%bS;J
}catch(SQLException e){} 9
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DBUtils.closeConnection(conn); rq/I` :
} fL=~NC"
} -B$2\ZE
public long getLast(){ jyZWVL:_
return lastExecuteTime; 9AJ7h9L
} XnWr5-;
public void run(){ N/K.%<h
long now = System.currentTimeMillis(); 9B7^lR
if ((now - lastExecuteTime) > executeSep) { SV~~Q_U9
//System.out.print("lastExecuteTime:"+lastExecuteTime); PJL=$gBgKk
//System.out.print(" now:"+now+"\n"); Rw:*'1
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); HEM9E&rL
lastExecuteTime=now; ssN6M./6
executeUpdate(); ktpaU,%
} 6'Worj
else{ E}nH1
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); ^*Yh@4\{JH
} ^kB8F"X
} $H9%J
} J:zU,IIJ
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 P IwFF}<(
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类写好了,下面是在JSP中如下调用。 f__cn^1
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<% De(Hw&
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CountBean cb=new CountBean(); ~,B5Hc 2
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); K$E3QVa
CountCache.add(cb); Nqa&_5"
out.print(CountCache.list.size()+"<br>"); q;][5
CountControl c=new CountControl(); !*%WuyCgr4
c.run(); ZP\-T*)l$
out.print(CountCache.list.size()+"<br>"); /VN f{p
%>