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: hg'!
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CountBean.java W?J[K;<
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/* +u:OAsR
* CountData.java <?Izfl6
* ND1%s &
* Created on 2007年1月1日, 下午4:44 |P0L,R
* k:)u7A+
* To change this template, choose Tools | Options and locate the template under T4Gw\Z%
* the Source Creation and Management node. Right-click the template and choose 4qXRDsbCf
* Open. You can then make changes to the template in the Source Editor. vP)~j1
*/ Rn_W|"
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package com.tot.count; 7"NJraQ6
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/** Fd,+(i D
* q.sQ Z]ty9
* @author =&:f+!1$
*/ B%:9P
public class CountBean { YGV#.
private String countType; 3=|2Gs?ut
int countId; #33RhJu5,
/** Creates a new instance of CountData */ "M0l;
public CountBean() {} k+r9h'd
public void setCountType(String countTypes){ cPaWJ+c
this.countType=countTypes; ?[1qC=[Z<
} jy@i(@Z
public void setCountId(int countIds){ G$|;~'E
this.countId=countIds; UQ?OD~7
} [67E5rk-
public String getCountType(){ 6 %k+0\d
return countType; :`^3MMLO
} bKJ7vXC05
public int getCountId(){ S}Y|s]6
return countId; {r2|fgi
} zpr@!76
} C9Z\G 3
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CountCache.java <eFAI}=s
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/* CC(*zrOd-
* CountCache.java S{(p<%)[
* q(tGbhQ
* Created on 2007年1月1日, 下午5:01 P(gVF|J?
* ;zE5(3x
* To change this template, choose Tools | Options and locate the template under fQy
C6C
* the Source Creation and Management node. Right-click the template and choose g_U~.?Db7
* Open. You can then make changes to the template in the Source Editor. z>p`!-'ID
*/ VMye5 P
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package com.tot.count; dGD^op,6g
import java.util.*; DEQE7.]3 q
/** CL'Xip')T
* xgT~b9
* @author hn\Q6f+
*/ K_+;"G
public class CountCache { oSA*~ N:
public static LinkedList list=new LinkedList(); b801OF
/** Creates a new instance of CountCache */ LUDJPIk
public CountCache() {} |~bR.IA
public static void add(CountBean cb){ 71/ m.w
if(cb!=null){ W
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list.add(cb); X})Imk7&E
} .F$|j1y
} 87pXv6'FQ
} !MJe+.
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CountControl.java L}jF#*Q%
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/* Tq\~<rEo
* CountThread.java d1TdH s\
* Jg|cvu-+
* Created on 2007年1月1日, 下午4:57 mhi90J c
* pjHRV[`AP
* To change this template, choose Tools | Options and locate the template under v]{uxlh
* the Source Creation and Management node. Right-click the template and choose o%WjJ~!zL
* Open. You can then make changes to the template in the Source Editor. 6(J4IzZ
*/ euj8p:+X
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package com.tot.count; Z 5)_B,E:X
import tot.db.DBUtils; ,c%K)KuPK.
import java.sql.*; Vl 19Md
/** 95^i/6Gl!P
* Gkv~e?Kc~^
* @author \SiHrr5
*/ LZc$:<J<6
public class CountControl{ B?#k W!wj
private static long lastExecuteTime=0;//上次更新时间 bKuj
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private static long executeSep=60000;//定义更新间隔时间,单位毫秒 I!@s6tG
/** Creates a new instance of CountThread */ "\/^/vn?
public CountControl() {} _))I.c=v
public synchronized void executeUpdate(){ QOV}5 0
Connection conn=null; jkF+g$B
PreparedStatement ps=null; H\| ]!8w5Z
try{ V'"I9R'1
conn = DBUtils.getConnection(); K/2. 1o;9
conn.setAutoCommit(false); {;&B^uz
]
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); UIf ZPf=
for(int i=0;i<CountCache.list.size();i++){ JS/M~8+Et
CountBean cb=(CountBean)CountCache.list.getFirst(); )Ab6!"'
CountCache.list.removeFirst(); q1f=&kGX~
ps.setInt(1, cb.getCountId()); .B'UQ|NR
ps.executeUpdate();⑴ 7Y32p'
//ps.addBatch();⑵ 1@%B?
} BeI;#m0
//int [] counts = ps.executeBatch();⑶ N~):c2Kp<9
conn.commit(); ?jri!]ux#
}catch(Exception e){ -*|:v67C&
e.printStackTrace(); /BMtcCPG!
} finally{ ms}f>f=
try{ @GG(7r\/B
if(ps!=null) { V \6(d
ps.clearParameters(); <8rgtu!VU
ps.close(); G`,u40a
ps=null; OQ(D5GR:4
} o#xgrMB
}catch(SQLException e){} LZM,QQ
DBUtils.closeConnection(conn); \T`["<
} .73zik
} aUW/1nQHa
public long getLast(){ kG)2%
return lastExecuteTime; wqlcLIJPR
} IX<r5!
public void run(){ ~^I\crx,U%
long now = System.currentTimeMillis(); jow7t\wk
if ((now - lastExecuteTime) > executeSep) { OGJ=VQA
//System.out.print("lastExecuteTime:"+lastExecuteTime); Y5ogi)
//System.out.print(" now:"+now+"\n"); iW|s|1mh3
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); ge0's+E+1
lastExecuteTime=now; K8
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executeUpdate(); =2
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} l#D-q/k?
else{ z wL3,!t
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); A3AP51
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} M o}H_8y
} T&r +G!2
} N%9h~G
//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 1$$37?FE
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类写好了,下面是在JSP中如下调用。 ,0!uem}1i
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<% 9W*.lf
CountBean cb=new CountBean(); V43nws"4
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); fyI_
CountCache.add(cb); D@8jGcz62
out.print(CountCache.list.size()+"<br>"); +w"_$Tj@;
CountControl c=new CountControl(); *Ph]F$ZP
c.run(); dG&2,n'f
out.print(CountCache.list.size()+"<br>"); "~u_\STn <
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