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: F25<+1kr
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CountBean.java oF&IC
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/* *C/KM;&
* CountData.java /T#o<D
* gDc]^K4>
* Created on 2007年1月1日, 下午4:44 %9YA^ri
* (lWKy9eTy`
* To change this template, choose Tools | Options and locate the template under 1 ?]J;9p
* the Source Creation and Management node. Right-click the template and choose QZYM9a>
* Open. You can then make changes to the template in the Source Editor. sBB:$X
*/ }u7D9_KU
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package com.tot.count; }JJ::*W2n
DzmqR0)
/** 9>zDJx
* 8"pA9Mr
* @author "{6KZ! +0
*/ +TWJNI
public class CountBean { +ks$UvtY
private String countType; xx}'l:}2]
int countId; 'T{pdEn8u
/** Creates a new instance of CountData */ Q}ZBr^*]1e
public CountBean() {} tJG (*
public void setCountType(String countTypes){ hf[IEK
this.countType=countTypes; =~;zVP
} ;lk f+,;
public void setCountId(int countIds){ 6%z`)d
this.countId=countIds; rOhA*_EG
} x6~Fb~aP
public String getCountType(){ # m_\1&g
return countType; t3M0La&
} KD9Ca $-
public int getCountId(){ B4 <_"0
return countId; OT"lP(,
} ]:Wb1
} R=QM;
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CountCache.java G)K9la<p
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/* "9.6\Y\*
* CountCache.java L7[X|zmy*x
* E'fX&[
* Created on 2007年1月1日, 下午5:01 @)06\h
* VN!^m]0
* To change this template, choose Tools | Options and locate the template under 00R%
* the Source Creation and Management node. Right-click the template and choose ir"* iL=
* Open. You can then make changes to the template in the Source Editor. =I{S;md
*/ U bpg92
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package com.tot.count; ud!r*E
import java.util.*; UfO'.8*v
/** &8.z$}m
* l!Nvn$hm
* @author Psg +\ 14
*/ N/`g?B[
public class CountCache { o(BYT9|.kw
public static LinkedList list=new LinkedList(); p$&_fzb
/** Creates a new instance of CountCache */ ~91uk3ST?
public CountCache() {} ;9
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public static void add(CountBean cb){ Rf&^th}TH
if(cb!=null){ >E{#HPpBi
list.add(cb); N n:m+ZDo^
} mT}Aje-L
} v UJ sFR
} sCuQB Z h
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CountControl.java \"{/yjO|4
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/* 1Q3%!~<\s
* CountThread.java Es_SCWJ
* [UUM^!1
* Created on 2007年1月1日, 下午4:57 >V3W>5 X
* 2I9{+>k
* To change this template, choose Tools | Options and locate the template under 3Ro7M=]
* the Source Creation and Management node. Right-click the template and choose BZ8h*|uT"
* Open. You can then make changes to the template in the Source Editor. 7ZrJ#n8?ih
*/ Q2??Kp]1
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package com.tot.count; i,\t]EJAU
import tot.db.DBUtils; >!CH7wX
import java.sql.*; mOgx&ns;j
/** >0[qi1
* &L2`L)
* @author T749@! v`z
*/ v#zfs'
public class CountControl{ p=je"{
private static long lastExecuteTime=0;//上次更新时间 ?d,acm
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 C _k_D
/** Creates a new instance of CountThread */ im_0ur&'
public CountControl() {} -uS7~Ww.a
public synchronized void executeUpdate(){ e{d_p%(
Connection conn=null; gqKC 4'G0
PreparedStatement ps=null; rGP?
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try{ 4p0IBfVG
conn = DBUtils.getConnection(); xX[{E x
conn.setAutoCommit(false); +K @J*W 1
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); E}E7VQjM
for(int i=0;i<CountCache.list.size();i++){ !dYX2!lvT
CountBean cb=(CountBean)CountCache.list.getFirst(); p2M?pV
CountCache.list.removeFirst(); EC:x,i
ps.setInt(1, cb.getCountId()); sP=2NqU3Q
ps.executeUpdate();⑴ BUboP?#%)
//ps.addBatch();⑵ AF07KA#
} Qt)7mf
//int [] counts = ps.executeBatch();⑶ t~udfOvY
conn.commit(); ~%::r_hQ
}catch(Exception e){ :5n"N5Go
e.printStackTrace(); +$Ddd`J'
} finally{ 4l#T_y
try{ SvCK;$:
if(ps!=null) { w2RESpi
ps.clearParameters(); #m[w=Pu}
ps.close(); 8O}A/*1FJ
ps=null; &)/H?S;yN
} pU\xzL D
}catch(SQLException e){} zS>:7eG
DBUtils.closeConnection(conn); xw/h~:NT
} UOOR0$4
} P+D|_3j
public long getLast(){ C'xU=OnA8
return lastExecuteTime; Mf,Mcvs
} h1D~AgZOVj
public void run(){ z.\[Va$@l
long now = System.currentTimeMillis(); '+GVozc6c"
if ((now - lastExecuteTime) > executeSep) { <y b=!
//System.out.print("lastExecuteTime:"+lastExecuteTime); HtS1N}@
//System.out.print(" now:"+now+"\n"); rVIb'sa
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); /s-jR]#VA
lastExecuteTime=now; 5O4&BxQ~}
executeUpdate(); q#':aXcv"
} -;DE&~p
else{ "|~B};|MFF
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); EZa{C}NQ$2
} QL|:(QM
} E|6Z]6[
} kcZ;SYosj
//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 -qnXa
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类写好了,下面是在JSP中如下调用。 \?Oly171
'KIi!pA.
<% ,nuDoc
CountBean cb=new CountBean(); .\hib.n3
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); { <ao4w6B
CountCache.add(cb); "ZK5P&d
out.print(CountCache.list.size()+"<br>"); *<h
CountControl c=new CountControl(); <8xP-(wk;
c.run(); McMK|_H
out.print(CountCache.list.size()+"<br>"); _<' kzOj
%>