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: B/q/sC
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CountBean.java cE 8vSQ%
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/* 7IBm(#
* CountData.java l~Kn-S{
* &UP@Sr0D7
* Created on 2007年1月1日, 下午4:44 :>nk63V (
* ioi0^aM
* To change this template, choose Tools | Options and locate the template under VxjEKc
* the Source Creation and Management node. Right-click the template and choose 1@yXVD/
* Open. You can then make changes to the template in the Source Editor. h#zx^F1
*/ EAF<PMb
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package com.tot.count; =}\]i*
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/** M~I M;my
* *0{MAm
* @author po*s
*/ $}TqBBe
public class CountBean { KD$ P\(5#
private String countType; b;]'Bo0K
int countId; %83PbH
/** Creates a new instance of CountData */ u9:;ft{}N
public CountBean() {} 'Vy$d<@s[
public void setCountType(String countTypes){ reM%GU
this.countType=countTypes; fbB(WE+
} |4-c/@D.~
public void setCountId(int countIds){ B5#a
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this.countId=countIds; UL;d H
} @_Aqk{3
public String getCountType(){ ^4Tr
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return countType; }CsUZ&* &
} 5U|f"3&8
public int getCountId(){ 86/CA[Y-
return countId; L}nj#z4g
} <%J dQ82?
} |?s%8c'w=
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CountCache.java Mb\~WUWI
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/* S#jH2fRo
* CountCache.java HGWwGd
* ]WN{8
* Created on 2007年1月1日, 下午5:01 (loUO;S=
* fL83:<RK
* To change this template, choose Tools | Options and locate the template under u~LisZ&tP
* the Source Creation and Management node. Right-click the template and choose 1)#<nk)I
* Open. You can then make changes to the template in the Source Editor. =zVbZ7
*/ 5Ag]1k{
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package com.tot.count; da\K>An>
import java.util.*; dT/Cn v=
/** j0=`Jf
* U( W#H|
* @author )#ic"UtR
*/ jV:U%
public class CountCache { 8f,jC+(
public static LinkedList list=new LinkedList(); 3tnYK&
/** Creates a new instance of CountCache */ m f4@g05
public CountCache() {} s=q\BmG
public static void add(CountBean cb){ BRoi`.b:
if(cb!=null){ z9h`sY~
list.add(cb); Se"\PxBR
} IZJV6clM
} TUy*wp9
} UT+\IzL
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CountControl.java k49CS*I
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/* l:+tl/
* CountThread.java .
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* 4I:Jb;k>
* Created on 2007年1月1日, 下午4:57 (`3Bi]7
* @=Ly#HuUM
* To change this template, choose Tools | Options and locate the template under umrRlF4M;
* the Source Creation and Management node. Right-click the template and choose <6dD{{J]>p
* Open. You can then make changes to the template in the Source Editor. jJ55Az?t:
*/ v
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package com.tot.count; ,"h$!k"$g
import tot.db.DBUtils; Nj#!L~^h,
import java.sql.*; CFul_qZ/e
/** htM5Nm[g
* bGK&W;Myk
* @author T%P0M*
*/ {:6VJ0s\
public class CountControl{ px4Z
private static long lastExecuteTime=0;//上次更新时间 K/MIDH
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 nn#A-x}~;b
/** Creates a new instance of CountThread */ 5U1@wfKE3>
public CountControl() {} bXJ,L$q
public synchronized void executeUpdate(){ N:L<ySJ7
Connection conn=null; eDaVoc3
PreparedStatement ps=null; akd~Z
try{ $|(roC(
conn = DBUtils.getConnection(); }{iR+MX
conn.setAutoCommit(false); Ao{wd1
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); M?}2
for(int i=0;i<CountCache.list.size();i++){ C,tlp
CountBean cb=(CountBean)CountCache.list.getFirst();
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CountCache.list.removeFirst(); eWwSD#N#
ps.setInt(1, cb.getCountId()); @q^WD_k
ps.executeUpdate();⑴ #\`6ZHW
//ps.addBatch();⑵ gkBat(Uc
} H[-zQ#I9
//int [] counts = ps.executeBatch();⑶ O,^,G<`
conn.commit(); >IoOCQQ*
}catch(Exception e){ !m_'<=)B4~
e.printStackTrace(); zw5EaY
} finally{ j{p0yuZ)<
try{ "<!|am(
if(ps!=null) { rB=1*.}FLc
ps.clearParameters(); {\]SvoJnJ
ps.close(); mT!~;]RrF
ps=null; PCw.NJd$
}
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}catch(SQLException e){} O~qB
DBUtils.closeConnection(conn); rzqCQZHL5
} vja^O
} _BR>- :Jr
public long getLast(){ L0+@{GP?
return lastExecuteTime; +pf 7
} B"+Ygvxb
public void run(){ 3l4k2
long now = System.currentTimeMillis(); ]j1BEO!Bg
if ((now - lastExecuteTime) > executeSep) { &p=~=&g=
//System.out.print("lastExecuteTime:"+lastExecuteTime); *l7
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//System.out.print(" now:"+now+"\n"); Bljh'Qp>C
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); E(u[?
lastExecuteTime=now; +?mZ_sf8w
executeUpdate(); VJ;'$SYx
} =FwFqjvl
else{ .Ta$@sP h}
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); zaoZCyJT%
} :U r%.0
} (%I`EAR
} Lo;T\CN
//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 Bb-x1{t
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类写好了,下面是在JSP中如下调用。 Xc
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<% !3HMGzt
CountBean cb=new CountBean(); v t(kL(}v
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); U6M4}q(N]
CountCache.add(cb); zEks4yd
out.print(CountCache.list.size()+"<br>"); DbOWnXV"o
CountControl c=new CountControl(); _Z8zD[l
c.run(); N|7._AR2
out.print(CountCache.list.size()+"<br>"); ;Vp&f%u+v
%>