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: /UR;,ts
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CountBean.java 0Nk!.gY
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/* |{%$x^KyJ
* CountData.java *cXi*7|=
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* Created on 2007年1月1日, 下午4:44 l8%BRG
* 0,#n_"
* To change this template, choose Tools | Options and locate the template under \SgBI/L^
* the Source Creation and Management node. Right-click the template and choose BP&]t1p
* Open. You can then make changes to the template in the Source Editor. \7o7~pll
*/ >G [:Q
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package com.tot.count;
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/** u
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* G_k_qP^:
* @author z-]ND
*/ hVZS6gU,x
public class CountBean { , a2=OV
private String countType; "N,@J-]/k
int countId; Gt,VSpb~s
/** Creates a new instance of CountData */ o=lZl_5/u;
public CountBean() {} v}!^RW'X
public void setCountType(String countTypes){ = 'e_9b\K
this.countType=countTypes; ;kG"m7-/
} <
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public void setCountId(int countIds){ *xx)j:Sc2
this.countId=countIds; r0\C2g_X
} {8;}y[R
public String getCountType(){ B1Z;
return countType; -" r4
} GbkDs-
public int getCountId(){ VhnIr#L+
return countId; qckRX+P`
} (II#9n)
} Z;dR:|%)
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CountCache.java k
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/* 7D~~<45ct
* CountCache.java #rz!d/)Q
* !Ap*PL
* Created on 2007年1月1日, 下午5:01 !"F8jA}
* urL@SeV+$
* To change this template, choose Tools | Options and locate the template under Cf
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* the Source Creation and Management node. Right-click the template and choose :[C|3KKe"
* Open. You can then make changes to the template in the Source Editor. s,|v,,<+
*/ W_
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package com.tot.count; ?;_Mx al'
import java.util.*; +QSH*(,
/** G 40
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* @author OSh'b$Z
*/ v>j<ky
public class CountCache { 0@
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public static LinkedList list=new LinkedList(); G}dq
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/** Creates a new instance of CountCache */ &pv*TL8
public CountCache() {} \SJX;7ST
public static void add(CountBean cb){ 3?+t%_[
if(cb!=null){ (
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list.add(cb); Ty;^3
} j0=H6Y
} O/&Qzt
} 3]&le[.
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CountControl.java |b!Bb<5
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/* Hm~.u.)\.
* CountThread.java wj Kc!iB
* GN+,9
* Created on 2007年1月1日, 下午4:57 T-js*
* A#F6~QX(.9
* To change this template, choose Tools | Options and locate the template under u3jLe=Y'\
* the Source Creation and Management node. Right-click the template and choose !G'wC0
* Open. You can then make changes to the template in the Source Editor. &}_tALg
*/ )~w
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package com.tot.count; _~y-?(46K
import tot.db.DBUtils; mF>{cVTF
import java.sql.*; {JfL7%
/** zUWWXC%R
* YTfi g{a
* @author 2H~E~6G
*/ #1'p?%K.
public class CountControl{ 5VGZ5,+<<
private static long lastExecuteTime=0;//上次更新时间 J8&0l&~6
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 EgOiJH
/** Creates a new instance of CountThread */ ~UwqQD1p
public CountControl() {} }fhGofN$e
public synchronized void executeUpdate(){ BMn`t@ !x
Connection conn=null; , LqfwA|
PreparedStatement ps=null; pA\"Xe&
try{ @~i :8
conn = DBUtils.getConnection(); Yg;7TKy
conn.setAutoCommit(false); ;;432^jD
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); LS<*5HWX
for(int i=0;i<CountCache.list.size();i++){ dZCjg0cx
CountBean cb=(CountBean)CountCache.list.getFirst(); iW[%|ddk
CountCache.list.removeFirst(); @A-E
ps.setInt(1, cb.getCountId()); z;&J9r$`
ps.executeUpdate();⑴ b>& 3XDz
//ps.addBatch();⑵
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} WvcPOt8Bp>
//int [] counts = ps.executeBatch();⑶ {C%f~j
conn.commit(); TO/SiOd
}catch(Exception e){ mU>lm7'
e.printStackTrace(); ]C-a[
} finally{ ]1q`N7
try{ #V@vz#bo=
if(ps!=null) { L~Xzo
ps.clearParameters(); :M@#.
ps.close(); X09i+/ICK
ps=null; byk9"QeY\
} LiEDTXRz
}catch(SQLException e){} '*K%\]
DBUtils.closeConnection(conn); CI|#,^
} ^W0eRT
} XU`vs`/
public long getLast(){ "OrF81
return lastExecuteTime; ?Elt;wL(
} h0-CTPQ7A
public void run(){ 'pT8S
long now = System.currentTimeMillis(); c:-n0m'i
if ((now - lastExecuteTime) > executeSep) { -[z1r)RZ
//System.out.print("lastExecuteTime:"+lastExecuteTime); Z:VT%-
//System.out.print(" now:"+now+"\n"); 6 _#C vQ
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); jZ,=tF
lastExecuteTime=now; #*+$o<Q]9
executeUpdate(); 1L4v X
} KP
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else{ ZP<OyX?
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); sGGi7%
} cu4 |!s`#
} Bdib)t[
} R`%O=S*]
//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 0BP=SCi
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类写好了,下面是在JSP中如下调用。 PWS5s^WM
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<% D!V*H?;U
CountBean cb=new CountBean(); @:P:`Zk
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); ~mT([V
CountCache.add(cb); dF+:9iiAm
out.print(CountCache.list.size()+"<br>"); "iuNYM5P
CountControl c=new CountControl(); v2vtkYQN
c.run(); J/c5)IB|
out.print(CountCache.list.size()+"<br>"); .R&jRtb/E
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