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: P-o/ax
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CountBean.java R*|y:T,H
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/* !<BJg3
* CountData.java >\6Tm
* S:aAR*<6
* Created on 2007年1月1日, 下午4:44 SaceIV%(
* @-qS[bV
* To change this template, choose Tools | Options and locate the template under E!nEB(FD
* the Source Creation and Management node. Right-click the template and choose WT;4J<O/
* Open. You can then make changes to the template in the Source Editor. -FftEeo7
*/ $a.fQ<,\X
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package com.tot.count; ?-C=_eZJ
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/** Jmg<mjq/G
* q#s:2#=
* @author jeLRS8];
*/ a@4
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public class CountBean { W}jel}:
private String countType; r&!Ebe-
int countId; $1lI6 =
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/** Creates a new instance of CountData */ l Oxz&m
public CountBean() {} J,q6
public void setCountType(String countTypes){ @N+ }cej
this.countType=countTypes; <5@VFRjc
} B}S!l>.z
public void setCountId(int countIds){ \"k[y+O],4
this.countId=countIds; )bqSM&SO
} ^V6cx2M
public String getCountType(){ y950Q%B]
return countType; [u*-~(
} Dnk}
public int getCountId(){ Yx#?lA2gx
return countId; c+S<U*
} 9d kuvk}:
} #dO8) t
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CountCache.java Y6W#uiqk
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/* @~p;.=1]F
* CountCache.java KYw~(+gHv2
* WzinEo{f
* Created on 2007年1月1日, 下午5:01 TwfQq`
* [pY1\$,
* To change this template, choose Tools | Options and locate the template under 9!XXuMWU<
* the Source Creation and Management node. Right-click the template and choose ce56$L8[
* Open. You can then make changes to the template in the Source Editor. `|uwR5
*/ 2eC`^
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package com.tot.count; P55QE+B
import java.util.*; RKi11z
/** s2f6;Yc
* C\`*_t
* @author >PbB /->
*/ 2|a5xTzH
public class CountCache { Q$bi:EyJXc
public static LinkedList list=new LinkedList(); C(Cuk4K
/** Creates a new instance of CountCache */ wjzR 8g0bQ
public CountCache() {} 57|RE5]|!
public static void add(CountBean cb){ KT3n-Y-,
if(cb!=null){ BT *z^ZH
list.add(cb); w|,BTM:e
} q 3nF\Me0
} qrr[QEFW
} N\{{:<Cp\
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CountControl.java L#|6Lnp^
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/* ?9Hs,J
* CountThread.java b'O>qQ
* hU|TP3*
* Created on 2007年1月1日, 下午4:57 c0U=Hj@@
* zz m[sX}
* To change this template, choose Tools | Options and locate the template under `b:yW.#w3l
* the Source Creation and Management node. Right-click the template and choose w7E7r?)Wl|
* Open. You can then make changes to the template in the Source Editor. bXNM.K
*/ ix+sT|>
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package com.tot.count; $! R]!s
import tot.db.DBUtils; 5jey%)=
import java.sql.*; `JAM]qB"
/** o;"Phc.
* V48o+ O
* @author
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*/ oYmLJzCf
public class CountControl{ N<e72x
private static long lastExecuteTime=0;//上次更新时间 E[a|.lnV
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 ^rh{
/** Creates a new instance of CountThread */ t3 rQ5m
public CountControl() {} lF#p1H>\
public synchronized void executeUpdate(){ cCBYM
Connection conn=null; MO-7yp:K
PreparedStatement ps=null; hdN[wC]
try{ :~wU/dEEiz
conn = DBUtils.getConnection(); _Squ%z:D
conn.setAutoCommit(false); ZW@%>_JR]
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); _^MkC}8
for(int i=0;i<CountCache.list.size();i++){ YwaWhBCIF
CountBean cb=(CountBean)CountCache.list.getFirst(); Ftw;T|
CountCache.list.removeFirst(); 3aUWQP2
ps.setInt(1, cb.getCountId());
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ps.executeUpdate();⑴ 4N[KmNi<
//ps.addBatch();⑵ Ql]+,^kA@
} tDQuimYu7
//int [] counts = ps.executeBatch();⑶ k];NTALOG
conn.commit(); UfSqiu
}catch(Exception e){ Op5S'
e.printStackTrace(); rv <_'yj
} finally{ nsN|[E8
try{ yp?a7t M
if(ps!=null) { nh]}KFO h
ps.clearParameters(); cH48)
ps.close(); x%RG>),U
ps=null; ~-2Gx
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} O6"S=o&
}catch(SQLException e){} /C
DBUtils.closeConnection(conn); gZ@z}CIw'
} T)o>U&KNP
} 6-Id{m x
public long getLast(){ wfQ^3HL
return lastExecuteTime; *O'`&J
} H&SoVi_V
public void run(){ \e9rXh%
long now = System.currentTimeMillis(); A-f,&TO
if ((now - lastExecuteTime) > executeSep) { h>"j!|#!s
//System.out.print("lastExecuteTime:"+lastExecuteTime); :^rt8>~
//System.out.print(" now:"+now+"\n"); N;S1s0FN
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); v2jpao<K
lastExecuteTime=now; $*+IsP!
executeUpdate(); kp3%"i&hD
} ({0:1*lF@
else{ D"M[}$P
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); .]YTS
} Om_-#S
} F1u2SltR
} YY4q99^K
//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 u';9zk/$
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类写好了,下面是在JSP中如下调用。 K$KVm^`
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<% Hu$y8_Udw
CountBean cb=new CountBean(); y.$Ae1a=
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); xmi@
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CountCache.add(cb); eX'U d%
out.print(CountCache.list.size()+"<br>"); G@zJf)u}
CountControl c=new CountControl(); iAo/Dnp2J
c.run(); >%H(0G#X
out.print(CountCache.list.size()+"<br>"); l5/gM[0_7
%>