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: "$Rl9(}
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CountBean.java ;J?!D x
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/* 0n3O;=[aV
* CountData.java b5H[~8mf
* i>e7 5`9
* Created on 2007年1月1日, 下午4:44 |dXS+R1
* .GS|H d
* To change this template, choose Tools | Options and locate the template under d~[>%&
* the Source Creation and Management node. Right-click the template and choose =ohdL_6
* Open. You can then make changes to the template in the Source Editor. Ye(0'*-jyc
*/ %A64 Y<K
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package com.tot.count; ikm4Y`c
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/** dd$\Q
* [ ra[~
* @author :l*wf/&z
*/ 9 -TFyZYU
public class CountBean { J.O;c5wL
private String countType; 7dU X(D,?
int countId; B`KpaE]
/** Creates a new instance of CountData */ 8qBw;A)
public CountBean() {} "pHQ
public void setCountType(String countTypes){ rtUdL,Hx
this.countType=countTypes; G-}
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} !)&-\!M>
public void setCountId(int countIds){ 6NZf!7,B
this.countId=countIds; &G'R{s&"
} =@ON>SmPs
public String getCountType(){ *4.f*3*
return countType; eH1Y!&`
} 2gFQHV
public int getCountId(){ 0e/~H^,SQ
return countId; uHwuw_eK`
} My5X%)T>P
} LFh(.
}
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CountCache.java *!nS4[d
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/* RNIfw1R
* CountCache.java K$K[fcj
* 5Pv>`E2^
* Created on 2007年1月1日, 下午5:01 7f
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* U(i2j)|^I3
* To change this template, choose Tools | Options and locate the template under BKJW\gS2
* the Source Creation and Management node. Right-click the template and choose 2U#OBvNU
* Open. You can then make changes to the template in the Source Editor. @c.QrKSaD
*/ ,sJ{2,]~
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package com.tot.count; K,^b=_]
import java.util.*; I@x*>
/** xi|iV1A
* E%$FX'8&
* @author VoP(!.Ua>7
*/ V:IoeQ]-
public class CountCache { F&lH5
public static LinkedList list=new LinkedList(); I
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/** Creates a new instance of CountCache */ #M<YNuE#"
public CountCache() {} $inKI
public static void add(CountBean cb){ -zWNQp$
if(cb!=null){ $$SJLV
list.add(cb); C$$Zwgy
} RR|X4h0.
} VrWQ] L
} QpA$='
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CountControl.java ;mg.} fI
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/* s:cJF
* CountThread.java #K*p1}rf
* pNZ3vTs6
* Created on 2007年1月1日, 下午4:57 ^=a:{["@!
* A-d<[@d0
* To change this template, choose Tools | Options and locate the template under Z78i7k }
* the Source Creation and Management node. Right-click the template and choose Sy]W4%
* Open. You can then make changes to the template in the Source Editor. wn|;Li
*/ H/k]u)Gtv
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package com.tot.count; eA{A3.f"Hz
import tot.db.DBUtils; _z1Qr?cY
import java.sql.*; 7IQaXcl
/** 'T(Q
* |onLJY7)
* @author {NcJL< ;tS
*/ VbTX;?
public class CountControl{ |`pBI0Sjo
private static long lastExecuteTime=0;//上次更新时间 <WnIJum
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 #DARZh U)
/** Creates a new instance of CountThread */ m%UF{I,
public CountControl() {} 5!pNo*QK
public synchronized void executeUpdate(){ bSn={O"M
Connection conn=null; :5'hd^Q
PreparedStatement ps=null; n*i&o;5
try{ TtnJ
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conn = DBUtils.getConnection(); 97<Z,q72Y
conn.setAutoCommit(false); epG]$T![
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); 1]Cbi7
for(int i=0;i<CountCache.list.size();i++){ xFJT&=Af W
CountBean cb=(CountBean)CountCache.list.getFirst(); wWSw0 H/
CountCache.list.removeFirst(); a8v\H8@X
ps.setInt(1, cb.getCountId()); >rSCf=
ps.executeUpdate();⑴ C1(RgY|
//ps.addBatch();⑵ &
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} ,izp^,`
//int [] counts = ps.executeBatch();⑶ Zop/ MeI
conn.commit(); 4^k8|#c
}catch(Exception e){ Dx=RLiU9
e.printStackTrace(); )2q
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} finally{ 4F6I7lu
try{ ~C3J-z<
if(ps!=null) { i3KAJ@
ps.clearParameters(); U#- 5",X|
ps.close(); S6\E
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ps=null; $=#Lf[|f=
} .r&CIL>
}catch(SQLException e){} 9V~hz (^
DBUtils.closeConnection(conn); 65VTKlDD
} OoRg:"9{#
} he@Y1CY
public long getLast(){ <%W&xk
return lastExecuteTime; S,udpQ7
} SUIu.4Mz
public void run(){ O_GHvLO=
long now = System.currentTimeMillis(); >wL!`:c'"
if ((now - lastExecuteTime) > executeSep) { "=KFag
//System.out.print("lastExecuteTime:"+lastExecuteTime); 9YB?wh'S[
//System.out.print(" now:"+now+"\n"); t-n'I/^5
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); c6=XJvz
lastExecuteTime=now; 3 ]@wa!`
executeUpdate(); U3-MvI,Q
} 9i
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else{ 8e
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//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); +2k{yl
} f}KV4'n
} !KT.p2\
} #;lEx'lKN
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 T+t7/PwC;
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类写好了,下面是在JSP中如下调用。 A|@d{g
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<% #c"05/=A
CountBean cb=new CountBean(); pIug$Ke_%
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); H;@0L}Nu+}
CountCache.add(cb); gNZ"Kr o6
out.print(CountCache.list.size()+"<br>"); `Fe/=]<$
CountControl c=new CountControl(); bD3 dT>(+
c.run(); K6)IBV;
out.print(CountCache.list.size()+"<br>"); I>w|80%%
%>