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: w]XBq~KO
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CountBean.java QKQy)g
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/* ArMe[t0$
* CountData.java z [{%.kA
* @@&;gWr;
* Created on 2007年1月1日, 下午4:44 $6Psq=|
* Hc !_o`[{l
* To change this template, choose Tools | Options and locate the template under h|Qh/jCX
* the Source Creation and Management node. Right-click the template and choose )[.URp&
* Open. You can then make changes to the template in the Source Editor. |zlwPi.
*/ 7.-|3Wcg
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package com.tot.count; ibL;99 #
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/** tO$M[P=b
* >MLqOUr#
* @author ~Q\[b%>J
*/ pTd@i1%Nr
public class CountBean { 1' s^W
private String countType; i^Q^F
int countId; KDk^)zv%!
/** Creates a new instance of CountData */ 9m>_qWaA
public CountBean() {} xRmB?kM3]5
public void setCountType(String countTypes){ EA72%Y9F
this.countType=countTypes; Jr
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} :-n4!z"k
public void setCountId(int countIds){ :PJjy6,1
this.countId=countIds; S5M t?v|K
} IYPI5qCR
public String getCountType(){ 'UCL?$
return countType; dXQWT@$y!E
} 7EUaf;d^
public int getCountId(){
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return countId; $TiAJ}:
} aQuENsB
} eS M!_2
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CountCache.java 4}`MV .
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/* ,;;~dfHm
* CountCache.java &kGSxYDk%
* XCY4[2*a>
* Created on 2007年1月1日, 下午5:01 Zf! 7pM
* nLQJ~("
* To change this template, choose Tools | Options and locate the template under pw
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* the Source Creation and Management node. Right-click the template and choose QaV*}W
* Open. You can then make changes to the template in the Source Editor. B _ >|Mo/
*/ l!2.)F` x
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package com.tot.count; 3/D fsv
import java.util.*; )U?W+0[=
/** pVM;xxJ
* [iz
* @author ^;e`ZtcI
*/ TM9>r :j'
public class CountCache { X^`ld&^*({
public static LinkedList list=new LinkedList(); ]|oqJ2P
/** Creates a new instance of CountCache */ ?0F#\0
public CountCache() {} C" {j0X`
public static void add(CountBean cb){ x.aUuC,$x
if(cb!=null){ gKnAw+u\
list.add(cb); OpfFF;"A'
} n!2|;|$}Z
} i?]!8Ji
} @%K 8oYK
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CountControl.java &yuerNK
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/* BC^WPr
* CountThread.java xxYFWvi
* vv3?ewr
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* Created on 2007年1月1日, 下午4:57 $kdfY'u
*
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* To change this template, choose Tools | Options and locate the template under Nz8iU@!a
* the Source Creation and Management node. Right-click the template and choose Pj$a$C`Z
* Open. You can then make changes to the template in the Source Editor. =0A{z#6
*/ 8EQ;+V
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package com.tot.count; "D+QT+sD
import tot.db.DBUtils; 5|Uub,
import java.sql.*; )+J?(&6
/** | e+m!G1G
* Mg].#
* @author 6%? NNEM
*/ !eW<4jYB
public class CountControl{ D6D*RTi4
private static long lastExecuteTime=0;//上次更新时间 9Rpj&0Is
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 ie)Qsw@
/** Creates a new instance of CountThread */ n
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public CountControl() {} hd900LA}
public synchronized void executeUpdate(){ '7$v@Tvnre
Connection conn=null; 3WhJ,~o-y
PreparedStatement ps=null; W`KkuQ4cM
try{ m1TPy-|1
conn = DBUtils.getConnection();
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conn.setAutoCommit(false); ;YB8X&H$
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); 0xsvxH"*
for(int i=0;i<CountCache.list.size();i++){
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CountBean cb=(CountBean)CountCache.list.getFirst(); db`<E
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CountCache.list.removeFirst(); t]V)3Ww
ps.setInt(1, cb.getCountId()); B$HQFdTli
ps.executeUpdate();⑴ Qx:+n`$/
//ps.addBatch();⑵ j \SDw
} IBR;q[Dj}
//int [] counts = ps.executeBatch();⑶ k,H4<")H
conn.commit(); *op7:o_
}catch(Exception e){ v / a/
e.printStackTrace(); PUI.Un2C_
} finally{
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try{ V[%r5!83H
if(ps!=null) { R,(^fM
ps.clearParameters(); !R-UL#w9W'
ps.close(); <1ai0]
ps=null; tW(E\#!|p<
} Z"P{/~HG
}catch(SQLException e){} @9^kl$
DBUtils.closeConnection(conn); v<O\ l~S
} >k:)'*
} ,5q^/h
public long getLast(){ t
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return lastExecuteTime; sbgRl%
} b{(:'.
public void run(){ Q.nEY6B_
long now = System.currentTimeMillis(); ?Hy++
if ((now - lastExecuteTime) > executeSep) { B]jh$@
//System.out.print("lastExecuteTime:"+lastExecuteTime); i
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//System.out.print(" now:"+now+"\n"); b*,R9
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); :yv!
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lastExecuteTime=now; RgEUTpX
executeUpdate(); Drg'RR><
} vWow^g
else{ L%fWa2P'
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); NvYgRf}uh
} D 4@=+
} ,2u]rLxx;
} qoOHWh&
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 VGTo$RH
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类写好了,下面是在JSP中如下调用。 "|f ;
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<% T%Z `:mf
CountBean cb=new CountBean(); ~]N%
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cb.setCountId(Integer.parseInt(request.getParameter("cid"))); ?
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CountCache.add(cb); Oyz=|[^,W
out.print(CountCache.list.size()+"<br>"); i3YAK$w;&
CountControl c=new CountControl(); aX0sy\Z]j
c.run(); X!r!lW
out.print(CountCache.list.size()+"<br>"); enZW2o97c
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