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: QmpP_eS >
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CountBean.java TZ2-%k#
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/* ksB-fOv*N
* CountData.java Xj^Hy"HC^~
* dfss_}R
* Created on 2007年1月1日, 下午4:44 AD ,
* uFzvb0O`O
* To change this template, choose Tools | Options and locate the template under %xq/eC7
* the Source Creation and Management node. Right-click the template and choose \LQ?s)~
* Open. You can then make changes to the template in the Source Editor. #:yh2y7a%
*/ dP0%<Q|
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package com.tot.count; #H;yXsR`
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/** 0"*!0s~
* ve [*t `
* @author NR*s7>
*/ 2th>+M~A
public class CountBean { 9F&s9(=\
private String countType; 8hK\Ya:mP
int countId; Vl0
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/** Creates a new instance of CountData */ U=<d;2N#
public CountBean() {} h]6"~ m
public void setCountType(String countTypes){ ]%RX\~Q.4
this.countType=countTypes; #fy#G}c
} [M7&
public void setCountId(int countIds){ km)5?
this.countId=countIds; ?W#>9WQi
} $<y10DfO
public String getCountType(){ ]Tb ?k+a
return countType; B_^ ~5_0:
} IwE{Zvr
public int getCountId(){ z2Pnni7Ys
return countId; 'g4t !__
} yK$.wd2,
} :|GC~JElo5
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CountCache.java tKnvNOhn
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/* 8f^QO:
* CountCache.java E!~Ok
* 9rB,7%@EL
* Created on 2007年1月1日, 下午5:01 Qj?qWVapA
* Z/|oCwR
* To change this template, choose Tools | Options and locate the template under QWo_Zg0"
* the Source Creation and Management node. Right-click the template and choose RS$!TTeQ
* Open. You can then make changes to the template in the Source Editor. /``4!jU
*/ Ddf7wszW
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package com.tot.count; 36NENzK
import java.util.*; 6vx0F?>_
/** rRTAWAs%T
* FD}hw9VyF@
* @author Z*Sa%yf
*/ x6, #Jp
public class CountCache { m.F \Mn
public static LinkedList list=new LinkedList();
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/** Creates a new instance of CountCache */ Fp)+>oT
public CountCache() {} <Ae1YHUY
public static void add(CountBean cb){ Dlc=[kf9
if(cb!=null){ ,qx;kJJ
list.add(cb); VSK!Pc.G}
} M![aty@
} xKilTh_.6
} W[5a'}OV
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CountControl.java H nKO
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/* Fk:yj 4'
* CountThread.java sH//*y
* /rKdxsI*
* Created on 2007年1月1日, 下午4:57 N36<EHq
*
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* To change this template, choose Tools | Options and locate the template under ]h(}%fk_
* the Source Creation and Management node. Right-click the template and choose px@:t}
* Open. You can then make changes to the template in the Source Editor. (J c} K
*/ tBtG- X2
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package com.tot.count; ^E)Kse.>
import tot.db.DBUtils; YbMeSU/sX
import java.sql.*; 24ojjxz+
/** .qjVw?E
* -`z`K08sT
* @author uF xrv
*/ *z2G(Uac
public class CountControl{ fl{wF@C6
private static long lastExecuteTime=0;//上次更新时间 a?LrSk`
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 6g/ <FM
/** Creates a new instance of CountThread */ >^cP]gGY
public CountControl() {} f0uzoeL<%
public synchronized void executeUpdate(){ hJqLH?Ri
Connection conn=null; taS2b#6\+
PreparedStatement ps=null; B8+J0jdg6%
try{ RC_w 1:h
conn = DBUtils.getConnection(); vvJ{fi
conn.setAutoCommit(false); UL81x72O
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); sSisO?F!Z
for(int i=0;i<CountCache.list.size();i++){ -WDU~VSU
CountBean cb=(CountBean)CountCache.list.getFirst(); "62vwWrwO
CountCache.list.removeFirst(); sV8}Gv
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ps.setInt(1, cb.getCountId()); W6.
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ps.executeUpdate();⑴ QXXB>gOY5
//ps.addBatch();⑵ J%G
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} Ls8@@b,t2
//int [] counts = ps.executeBatch();⑶ `Yk~2t"V
conn.commit(); [>5<&[A
}catch(Exception e){ z6~cm6 j
e.printStackTrace(); Kjw4,z%\94
} finally{ gyqM&5b
try{ >]6f!;Rt
if(ps!=null) { fE1B1j<
ps.clearParameters(); `6`p ~
ps.close(); en"]u,!
ps=null; \#LkzN8
} bSOxM/N
}catch(SQLException e){} K?;_T$^K
DBUtils.closeConnection(conn); 3\x@G)1
} d~i WV6Va
} +D[|Mi
public long getLast(){ S6k
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return lastExecuteTime; W'aZw9
} Yt]tRqrh;T
public void run(){ D?+\"lI
long now = System.currentTimeMillis(); |Z]KF>S]
if ((now - lastExecuteTime) > executeSep) { *&WkorByW
//System.out.print("lastExecuteTime:"+lastExecuteTime); $]V,H"
//System.out.print(" now:"+now+"\n"); lSMv9:N
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); )?5027^
lastExecuteTime=now; nz{
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executeUpdate(); LAe>XF-5
} )7$1Da|.
else{ =mVWfFL
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); }tq
} `pMI@"m
} B3x 4sKs
} gYeKeW3)
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 oXC|q-(C
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类写好了,下面是在JSP中如下调用。 [/h3HyZ.
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<% #&V7CYJ
CountBean cb=new CountBean();
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cb.setCountId(Integer.parseInt(request.getParameter("cid"))); 0 ge"ISK
CountCache.add(cb); :;Lt~:0b~
out.print(CountCache.list.size()+"<br>"); v|!u]!JM
CountControl c=new CountControl(); l#%qF Db
c.run(); R07]{
out.print(CountCache.list.size()+"<br>"); g mdJ8$
%>