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: D -Goi-4
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CountBean.java >
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/* ;Kq/[$~0
* CountData.java >k gL N
* D^+#RR'#,
* Created on 2007年1月1日, 下午4:44 Bnju_)U5)
* W`}C0[%VW
* To change this template, choose Tools | Options and locate the template under u{F^Ngy
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* the Source Creation and Management node. Right-click the template and choose XH_XGzBQS
* Open. You can then make changes to the template in the Source Editor. dd+[FU
*/ %#!pAUP\&
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package com.tot.count; 7X\azL
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/** Y|eB;Dm1q
* [yzDa:%
* @author 9G7lPK
*/ Rj&V~or
public class CountBean { ,2H@xji
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private String countType; . zM
int countId; rQ0V3x1"Qx
/** Creates a new instance of CountData */ b2x8t7%O
public CountBean() {} 5r;M61
public void setCountType(String countTypes){ ]#n,DU}V
this.countType=countTypes; }]0f -}
} $vlc@]~d`&
public void setCountId(int countIds){ &X0qH8W
this.countId=countIds; a@[y)xa$Z
} <k2Qcicy
public String getCountType(){ SDY!!.
return countType; ^j"*-)R
} JTH8vk:@
public int getCountId(){ Q+d9D1b
return countId; qla$}dnvc
} Im9^mVe
} J1,\Q<
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CountCache.java `(j}2X'[
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/* =d#3& R]p
* CountCache.java q$[x*!~
* >P7|-bV
* Created on 2007年1月1日, 下午5:01 #!,tId
* n@9*>DU
* To change this template, choose Tools | Options and locate the template under <mE)&7C
* the Source Creation and Management node. Right-click the template and choose MV"aO@
* Open. You can then make changes to the template in the Source Editor. Z-(Vfp4
*/ }nrl2yp:%
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package com.tot.count; :Gyv%>.
import java.util.*; e<_p\LiOS
/** K2J DG.<
* 2=pVX
* @author tlo"tl_]
*/ w!{g^*R+!
public class CountCache { _h#SP+>
public static LinkedList list=new LinkedList(); j(Tt-a("z
/** Creates a new instance of CountCache */ we6']iaV
public CountCache() {} gie}k)&M
public static void add(CountBean cb){ !"\UT&
if(cb!=null){ (;^VdiJ
list.add(cb); oi4tj.!J
}
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} 9o7E/wP
} ;qT~81
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CountControl.java Jq1 Zb
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/* !Kv.v7'N/k
* CountThread.java ]<D9Q>
* E]PHO\f-m}
* Created on 2007年1月1日, 下午4:57 \D8d!gr
* ^Xjh?+WM
* To change this template, choose Tools | Options and locate the template under so h3d
* the Source Creation and Management node. Right-click the template and choose E7E>w#T5
* Open. You can then make changes to the template in the Source Editor. Bor_Kib
*/ ;5tSXgGw7
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package com.tot.count; e-Z+)4fH
import tot.db.DBUtils; .%>UA|[~:
import java.sql.*; LO8V*H(
/** X^4HYm
* >U@7xeK
* @author >/;V_(
*/ P@LYa_UFsN
public class CountControl{ 4}sfJ0HhX
private static long lastExecuteTime=0;//上次更新时间 (hTe53d<S?
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 @$ E&H`da
/** Creates a new instance of CountThread */ 7_>No*[
public CountControl() {} E )D*~2o/
public synchronized void executeUpdate(){ (xffU%C^
Connection conn=null; FVkb9(WW
PreparedStatement ps=null; ?[Xv(60]
try{ F3/aq+<P[
conn = DBUtils.getConnection(); )24r^21.q
conn.setAutoCommit(false); R.Xh&@f`
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); ^]}UyrOn
for(int i=0;i<CountCache.list.size();i++){ &i*/}OZz
CountBean cb=(CountBean)CountCache.list.getFirst(); c%Y%c2([
CountCache.list.removeFirst(); p(/PG+
ps.setInt(1, cb.getCountId()); >pjmVlw?
ps.executeUpdate();⑴ +ZeHZjd
//ps.addBatch();⑵ VYj hU?I
} Y9fktg.
//int [] counts = ps.executeBatch();⑶ _W]qV2j
conn.commit(); e_6VPVa
}catch(Exception e){ >h>X/a(=~
e.printStackTrace(); 3B:U>F,]4
} finally{ 4R-Y9:^t
try{ Wi_5.=
if(ps!=null) { V,?i]q;5
ps.clearParameters(); wS"[m>.{v
ps.close(); [r%WVf.#d
ps=null; 6tXx--Nh
} q6'3-@%
}catch(SQLException e){} isK~=
DBUtils.closeConnection(conn); s"b()JP
} -.=q6N4
} wb^Yg9
public long getLast(){ T4n.C~
return lastExecuteTime; 4G;FpWQm
} Onoi^MDy
public void run(){ 6#P\DT
long now = System.currentTimeMillis(); ?r"][<
if ((now - lastExecuteTime) > executeSep) { sU"D%G
//System.out.print("lastExecuteTime:"+lastExecuteTime); rug^_d=B
//System.out.print(" now:"+now+"\n"); +#~=QT9
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); 4/;
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lastExecuteTime=now; hXr`S4aJ
executeUpdate(); )%'Lm
} | _/D-m*
else{ Erz{{kf]1V
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); w5,p9f}.
} /rp.H'hC
} J~7E8
} i-oi?x<u&(
//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 Wlm%W>%
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类写好了,下面是在JSP中如下调用。 u=B_cA}:
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<% n|`L>@aw,
CountBean cb=new CountBean(); *xB9~:
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); `M?C(
CountCache.add(cb); ]eA<
out.print(CountCache.list.size()+"<br>"); p-n_
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CountControl c=new CountControl(); ])paU8u
c.run(); m[&]#K6
out.print(CountCache.list.size()+"<br>"); >o #^r;
%>