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: ]CLt Km
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CountBean.java A\xvzs.d
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/* oY;=$8y<q
* CountData.java ?-.Qv1hs6p
* bSbUf%LKt
* Created on 2007年1月1日, 下午4:44 aJ;6!WFW
* 1uz7E
* To change this template, choose Tools | Options and locate the template under EGD&/%aC
* the Source Creation and Management node. Right-click the template and choose tZ4Zj`x|^
* Open. You can then make changes to the template in the Source Editor. Wbra*LNU
*/ bIs@CDB
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package com.tot.count; s}m.r5
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/** 0J
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* |-vc/t2k>T
* @author @-d0~.S
*/ )$Tcip`
public class CountBean { XHX$Ur9
private String countType; y&F0IJ|`@M
int countId; bi=IIVlH
/** Creates a new instance of CountData */ ??MF8uv
public CountBean() {} >o45vB4o
public void setCountType(String countTypes){ A]x'!qa@=
this.countType=countTypes;
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} @20~R/vh
public void setCountId(int countIds){ 3d_PY,=1
this.countId=countIds; k2axGq
} dF
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public String getCountType(){ Z#Q)a;RA
return countType; xW hi>
} e
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public int getCountId(){ t93iU?Z
return countId; Td|x~mZv:
} P. V #
} S zqY@
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CountCache.java 4R8W ot
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/* +0)zB;~7
* CountCache.java F~qiNV
* (";{@a %
* Created on 2007年1月1日, 下午5:01 `% a+LU2
* utJz e
* To change this template, choose Tools | Options and locate the template under gJn_Z7Mg J
* the Source Creation and Management node. Right-click the template and choose $IdY(f:.:5
* Open. You can then make changes to the template in the Source Editor. >mWu+Nn:
*/
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package com.tot.count; `;'fCO!
import java.util.*; [>pqf
/** HJV8P2f8`
* QqS?-
* @author "-tTN
*/ P@RUopu,i
public class CountCache { lMcSe8LBQa
public static LinkedList list=new LinkedList(); vW\|%
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/** Creates a new instance of CountCache */ W@:a3RJ
public CountCache() {} :zL.dJwa
public static void add(CountBean cb){ TAXl73j_CY
if(cb!=null){ ~582'-=+
list.add(cb); KPT@I3P
} p]7Gj&a
} ;4g_~fB
} #9 Fe,
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CountControl.java /p&)bL
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/* (ex^=fv
* CountThread.java guD?~-Q
* lQ}e"#<
* Created on 2007年1月1日, 下午4:57 &dC #nw
* @3UVl^T
* To change this template, choose Tools | Options and locate the template under =XT'D@q~W
* the Source Creation and Management node. Right-click the template and choose wu2AhMGmw
* Open. You can then make changes to the template in the Source Editor. h/CF^0m"!
*/ $_.m<
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package com.tot.count; a%wK[yVp
import tot.db.DBUtils; #=MQE
import java.sql.*; h0N*hx
/** jJ' LM>e
*
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* @author M~G1ZB
*/ SwDUg}M~
public class CountControl{ {mlJ E>~%
private static long lastExecuteTime=0;//上次更新时间 i>M*ubWE4@
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 ? }k~>. \
/** Creates a new instance of CountThread */ 7 -(LWH
public CountControl() {} YS_9M Pi
public synchronized void executeUpdate(){ h)M9Oup`
Connection conn=null; Kk^tQwj/QE
PreparedStatement ps=null; <N{pMz
try{ iZ`1Dzxgk
conn = DBUtils.getConnection(); us.+nnd
conn.setAutoCommit(false); N1V qK
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); Q&rf&8iH
for(int i=0;i<CountCache.list.size();i++){ J)l]<##
CountBean cb=(CountBean)CountCache.list.getFirst(); `P `nqn
CountCache.list.removeFirst(); VH{SE7
ps.setInt(1, cb.getCountId()); l;e&p${P
ps.executeUpdate();⑴ >e4
//ps.addBatch();⑵ {d;eZt
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} ,]N!I%SI
//int [] counts = ps.executeBatch();⑶ SZ9xj^"g
conn.commit(); =f)S=0U F
}catch(Exception e){ VesO/xG<
e.printStackTrace(); o3;u*f0rWn
} finally{ Cf_Ik
try{ PAe2hJ
if(ps!=null) { zN\~v
ps.clearParameters(); NRS!Ox
ps.close(); {C%/>e2-%
ps=null; N_vVEIO9
} u+]v.Mt
}catch(SQLException e){} |wf:|%
DBUtils.closeConnection(conn); zS:89y<
} lPS A
} t9&z|?Vz
public long getLast(){ E(T6s^8
return lastExecuteTime; xNNoB/DR
} uTRa]D_q
public void run(){
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long now = System.currentTimeMillis(); ];P^q`n=.
if ((now - lastExecuteTime) > executeSep) { Ih}I`wY-
//System.out.print("lastExecuteTime:"+lastExecuteTime); o8P 5C4y
//System.out.print(" now:"+now+"\n"); hfY
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// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); ? OBe!NDf
lastExecuteTime=now; ^i{B8]2,
executeUpdate(); s0Ii;7fA{
} &)vX7*j
else{ xDBEs*
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); F<?e79},`
} ^uW!=%D
} qYFol#=%
} GLb}_-|
//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 7"f$;CN?~
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类写好了,下面是在JSP中如下调用。 fB5Bh;K
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<% M* W=v
CountBean cb=new CountBean(); o'Q)V
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); ^zGgvFf>
CountCache.add(cb); " 7!K'i
out.print(CountCache.list.size()+"<br>"); ]lF'o&v]
CountControl c=new CountControl(); jlER_I]
c.run(); :^SpKe(7
out.print(CountCache.list.size()+"<br>"); H^Xw<Z=
%>