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: GW/WUzK
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CountBean.java CmHyAw(
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/* p9iu:MucD<
* CountData.java U=QA e
* #U"1 9@|}
* Created on 2007年1月1日, 下午4:44 hZU1O
* 8R?I`M_b
* To change this template, choose Tools | Options and locate the template under 7n&yv9"
* the Source Creation and Management node. Right-click the template and choose &d,Wy"WPi
* Open. You can then make changes to the template in the Source Editor. cmDT
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*/ D/:3RZF
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package com.tot.count; [.-a$J[4+F
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/** `D2Mss$!
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* @author s)w9%
*/ !\x?R6K
public class CountBean { m&/=&S
private String countType; PeNF+5s/K
int countId; [h-norB((
/** Creates a new instance of CountData */ (p,}'I#i*
public CountBean() {} J-XTN"O
public void setCountType(String countTypes){ k|B2@{
this.countType=countTypes; gtYRV*^q
} Y[G9Vok
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public void setCountId(int countIds){ ]sL45k2W
this.countId=countIds; N!c
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} CDCC1B G"
public String getCountType(){ ti9}*8
return countType; &t3Jv{
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public int getCountId(){ 88o:NJ}_
return countId; XTo8,'UaP
} [ {cC
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CountCache.java 28oJFi]
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/* .'lN4x
* CountCache.java P4 6,o
* y x;h
* Created on 2007年1月1日, 下午5:01 %h/! Y<%
* #U@| J}a
* To change this template, choose Tools | Options and locate the template under zYr z08PJ
* the Source Creation and Management node. Right-click the template and choose qjLo&2)
* Open. You can then make changes to the template in the Source Editor. 98UlNP
*/
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package com.tot.count; 9L HuS
import java.util.*; _}ele+
/** r/Dd&x
* A.U'Q|
* @author b n-=fb(
*/ x'i0KF
public class CountCache { ,`
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public static LinkedList list=new LinkedList(); H,|YLKg-|
/** Creates a new instance of CountCache */ / O)6iJ
public CountCache() {} %wW'!p-<
public static void add(CountBean cb){ @L8;VSI
if(cb!=null){ "L@g3g?|`
list.add(cb); }Vl^EAR
} 1b[NgOXY=
} P`
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} qTy v.#{y
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CountControl.java q+%!<]7X
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/* }`]]b+_b>@
* CountThread.java ?O7iK<5N
* (9'be\
* Created on 2007年1月1日, 下午4:57 iNLDl~uU
* T#r=<YH[C
* To change this template, choose Tools | Options and locate the template under \(bj(any
* the Source Creation and Management node. Right-click the template and choose +{*)}[w{x
* Open. You can then make changes to the template in the Source Editor. ?i%nMlcc
*/ r=\P!`{5
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package com.tot.count; A^L?_\e6
import tot.db.DBUtils; 6sy,A~e
import java.sql.*; H &fTh
/** nX 8B;*p6b
* }VZM,.w
* @author U!NI_uk
*/ I4:rie\hjC
public class CountControl{ c/RT0xql*
private static long lastExecuteTime=0;//上次更新时间 vX 1W@s
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 B!iFmkCy
/** Creates a new instance of CountThread */ Y{j7Q4{
public CountControl() {} xD^wTtT
public synchronized void executeUpdate(){ E4Zxv*
Connection conn=null; f-&ATTx`J
PreparedStatement ps=null; 4znH$M>bU
try{ SdSgn |S
conn = DBUtils.getConnection(); KG-y)qXu
conn.setAutoCommit(false); 9BO|1{
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); $$\V2%v
for(int i=0;i<CountCache.list.size();i++){ G
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CountBean cb=(CountBean)CountCache.list.getFirst(); Q-3r}jJe
CountCache.list.removeFirst(); i)[kubM
ps.setInt(1, cb.getCountId()); !YY6o
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ps.executeUpdate();⑴ BPh".R J
//ps.addBatch();⑵ ~;!BDLMC6
} (HPz
//int [] counts = ps.executeBatch();⑶ /Bh>
conn.commit(); #1B}-PGCm
}catch(Exception e){ G"{4'LlA
e.printStackTrace(); v`
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} finally{ S7Znz@
try{ ^glX1 )
if(ps!=null) { ^K"ZJ6?+1
ps.clearParameters(); z>7=k`x`:
ps.close(); )O9f hj)
ps=null; C/bxfp{?
} u |'8a1
}catch(SQLException e){} z+ uL "PG[
DBUtils.closeConnection(conn); "cNg:
} K[e`t%2_
} 4Q@\h=r
public long getLast(){ i},d[
return lastExecuteTime; +)?, {eE|
} WFRsSp2
public void run(){ R08&cd#$
long now = System.currentTimeMillis(); hN[X 1*
if ((now - lastExecuteTime) > executeSep) { )y(oHRCp->
//System.out.print("lastExecuteTime:"+lastExecuteTime); j{)fC]8H
//System.out.print(" now:"+now+"\n"); o
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// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); pa>p%
lastExecuteTime=now; J9NsHr:A[
executeUpdate(); &ycjSBK
} ~KJ,SLzhx9
else{ 0h^uOA; c
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); #]k0Z~Bl
} E2h(w_l
} JIVo=5c}
} Ob7zu"zr
//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 S> .q5
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类写好了,下面是在JSP中如下调用。 L7X7Zt8%
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<% >y]?MGk
CountBean cb=new CountBean(); 9*BoYFw92*
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); iK ohuZr
CountCache.add(cb); ,<7"K&
out.print(CountCache.list.size()+"<br>"); lB=(8.
CountControl c=new CountControl(); GVeL~Q
c.run(); @mvIt
out.print(CountCache.list.size()+"<br>"); tX@0:RX%
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