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: UUb n7&
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CountBean.java Kjbt1n
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/* :B(F?9qK
* CountData.java 3I!xa*u
* mEi+Tj zp
* Created on 2007年1月1日, 下午4:44 O^fg~g X
* 8\,|T2w,X
* To change this template, choose Tools | Options and locate the template under A)9[.fhx
* the Source Creation and Management node. Right-click the template and choose yKE[,"
* Open. You can then make changes to the template in the Source Editor. ,>" rcd
*/ CNwYQe-i
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package com.tot.count; .yz-o\,gF%
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/** scmn-4j'{
* mmk]Doy?#
* @author [Xp{ztGE
*/ %7tQam
public class CountBean { [$; \1P/
private String countType; z{h#l!Edh
int countId; }1]E=!?)&
/** Creates a new instance of CountData */ :eaqUW!Y
public CountBean() {} \QF\Bh
public void setCountType(String countTypes){ En&bwLu:s
this.countType=countTypes; f:$LVpXS-
} Hya ";'
public void setCountId(int countIds){ 5rG&Z5
this.countId=countIds; _@es9
} K:}~8 P>^
public String getCountType(){ Be"Swz(n
return countType; HI}$Z=C
} BR8W8nRb
public int getCountId(){ mNcoR^(VN
return countId; cSdkhRAn
} mHTZ:84
} 4%l
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CountCache.java rNzsc|a:
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/* /4 zO
* CountCache.java j.C)KwelBS
* *2MM
* Created on 2007年1月1日, 下午5:01 e&&;"^@-
* Q_}i8p'
* To change this template, choose Tools | Options and locate the template under cG%ttfq\
* the Source Creation and Management node. Right-click the template and choose V,,/}f'
* Open. You can then make changes to the template in the Source Editor. )9_jr(s
*/ &cj/8A5-
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package com.tot.count; KX*Hev'K
import java.util.*; $`q8-+{
/** a
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* KM$5ZbCF:
* @author NwQexYm1_
*/ z-(#Mlq:!
public class CountCache { 1_JxDT,=>
public static LinkedList list=new LinkedList(); wg6![Uh
/** Creates a new instance of CountCache */ Lo,z7"8
public CountCache() {} urGk_.f
public static void add(CountBean cb){ wk {9
if(cb!=null){ z`gdE0@;d3
list.add(cb); QusEWq)}<
} StUiL>9T#
} w)bLdQ
} {"33 .^=
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CountControl.java by*>w/@9)k
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/* x?Wt\<|h!
* CountThread.java UN`F|~@v
* ^+Ez[S{8
* Created on 2007年1月1日, 下午4:57 ejj|l
* >M .?qs4
* To change this template, choose Tools | Options and locate the template under "cerg?ix
* the Source Creation and Management node. Right-click the template and choose wK8/`{B9
* Open. You can then make changes to the template in the Source Editor. />fP )56*
*/ 'BT}'qN
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package com.tot.count; G?-27Jk8
import tot.db.DBUtils; U_a)g
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import java.sql.*; 8kZ~
/** v4L#^Jw(^p
* j=v 1:E
* @author '8~cf
*/ fgFBOpG%Gq
public class CountControl{ '"}|'J
private static long lastExecuteTime=0;//上次更新时间 < 4DWH
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 $[VeZ-
/** Creates a new instance of CountThread */ DM6oMT
public CountControl() {} l*[ .
public synchronized void executeUpdate(){ myH:bc>6
Connection conn=null; 9IL#\:d1
PreparedStatement ps=null; 4 !lbwqo
try{ iKB8V<[\T
conn = DBUtils.getConnection(); +Q, 0kv
conn.setAutoCommit(false); LV:oNK(
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); )>LQ{X.
for(int i=0;i<CountCache.list.size();i++){ t1HUp dHY
CountBean cb=(CountBean)CountCache.list.getFirst(); `n8) o %E9
CountCache.list.removeFirst(); 8$avPD3jx
ps.setInt(1, cb.getCountId()); sg12C
ps.executeUpdate();⑴ SdUtAC2
//ps.addBatch();⑵ S~vbISl
} ZTG*|
//int [] counts = ps.executeBatch();⑶ ~p~8T
conn.commit(); +3e(psdg
}catch(Exception e){ OVO0Emv
e.printStackTrace(); [KkLpZG
} finally{ k/nOz*
try{ {! RW*B
if(ps!=null) { JH2?^h|{
ps.clearParameters(); cL*D_)?8
ps.close(); E0=-6j
ps=null; 'MKkC(]4
} =Mq=\T
}catch(SQLException e){} Tgp}k%R~
DBUtils.closeConnection(conn); R!xs;|]
} )!MeSWGq
} '<f4POy!
public long getLast(){ HZ=Dd4!
return lastExecuteTime; 8?W!U*0aS
} 87EI<\mP
public void run(){ );$Uf!v4
long now = System.currentTimeMillis();
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if ((now - lastExecuteTime) > executeSep) { pTZPOv#?Q
//System.out.print("lastExecuteTime:"+lastExecuteTime); 0CY_nn#3
//System.out.print(" now:"+now+"\n"); %"
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// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); #{(?a.:
lastExecuteTime=now; P,!W\N%3
executeUpdate(); D8_m_M|P
} 'j$iS W&
else{ io
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//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); h 88iZK
} f(DGC2R
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} A<iF37.
} V_U$JKJ1=
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 q
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类写好了,下面是在JSP中如下调用。 H;s0|KRgJ
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<% mKZ?H$E%%
CountBean cb=new CountBean(); EA75
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cb.setCountId(Integer.parseInt(request.getParameter("cid"))); _6qf>=qQ`"
CountCache.add(cb); 6KhHS@Z
out.print(CountCache.list.size()+"<br>"); GZQ)TzR
CountControl c=new CountControl(); J),7ukLu^
c.run(); r4NI(\gU
out.print(CountCache.list.size()+"<br>"); u7@|fND 7
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