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: T$ )dc^
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CountBean.java A#6\5u
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/* f2"1^M
* CountData.java ?$#,h30
* nBA0LIb
* Created on 2007年1月1日, 下午4:44 71# ipZ
* Cd"iaiTD0
* To change this template, choose Tools | Options and locate the template under Zh]FL8[
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* the Source Creation and Management node. Right-click the template and choose g}B|ZRz+{
* Open. You can then make changes to the template in the Source Editor. @m=xCg.Z
*/ b&V}&9'[M;
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package com.tot.count; =R
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/** c=}#8d.
* LZB=vc|3/
* @author eBmBD"$
*/ hZobFf
public class CountBean { G-)Q*p{i|
private String countType; C&QT-|
int countId;
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/** Creates a new instance of CountData */ o=1M<dL
public CountBean() {} u,R;=DNl
public void setCountType(String countTypes){ RnX:T)+o
this.countType=countTypes; f/Lyc=-]
} cN5,\I.
public void setCountId(int countIds){ !A\Qwg>
this.countId=countIds; \MA4>
} d/k70Ybk
public String getCountType(){ B7fV_-p: G
return countType;
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} 8a^E{x@HT
public int getCountId(){ 5Cp6$V|/kv
return countId; !Cpy
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} vThK@P!s
} O7_u9lz2
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CountCache.java !4(X9}a
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/* :|\{mo1NB
* CountCache.java ]R$
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* GYX/G>-r
* Created on 2007年1月1日, 下午5:01 8~=<!(M)m/
* 'TF5CNX
* To change this template, choose Tools | Options and locate the template under 02lI-xHe
* the Source Creation and Management node. Right-click the template and choose !`rR;5&sT
* Open. You can then make changes to the template in the Source Editor. ^rmcyy8;g
*/ 'V=i;2mB*
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package com.tot.count; l1&NU'WW
import java.util.*; _i=431Z40
/** 7$l! f
* W]]@pbG"H\
* @author NEpomE(>x
*/ BJ0P1vh6M
public class CountCache { }'y=JV>l
public static LinkedList list=new LinkedList(); R<J1bH1n3
/** Creates a new instance of CountCache */ VuOZZ7y
public CountCache() {} =peodj^
public static void add(CountBean cb){ fr\"MP
if(cb!=null){ ^4WNP
list.add(cb); V6:S<A
} ,-11w7y\
} Y -Zw'
} "h-G=vo,kl
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CountControl.java g9A8b(>F&@
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/* @2LpI*]C
* CountThread.java s\)0f_I
* 6%hr]>L
* Created on 2007年1月1日, 下午4:57 7wivu*0
* Y;X_E7U
* To change this template, choose Tools | Options and locate the template under m5wfQ_}}ss
* the Source Creation and Management node. Right-click the template and choose o_.f7|U!
* Open. You can then make changes to the template in the Source Editor. (Q_J{[F
*/ ;
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package com.tot.count; UP18?uM
import tot.db.DBUtils; KlMSkdmW
import java.sql.*; 3tO=
/** AG3iKk??T
* m#\I&(l+
* @author [9wuaw"~[Z
*/ )Vn(J#s
public class CountControl{ }de{-
private static long lastExecuteTime=0;//上次更新时间 Yq6e=?-
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 X 5.%e&`
/** Creates a new instance of CountThread */ 1Mf tq4nq
public CountControl() {} DLigpid
public synchronized void executeUpdate(){ "Je*70LG#
Connection conn=null; FN$sST
PreparedStatement ps=null; kM0TQX)$m
try{ Ihd{@6m
conn = DBUtils.getConnection(); 8=GgTpO5
conn.setAutoCommit(false); s?fO)7ly
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); +f}u.T_#
for(int i=0;i<CountCache.list.size();i++){ k10g %K4g
CountBean cb=(CountBean)CountCache.list.getFirst(); ~rUcko8
CountCache.list.removeFirst(); f: j9ze
ps.setInt(1, cb.getCountId()); G^G= .9O
ps.executeUpdate();⑴ )p$a1\~m
//ps.addBatch();⑵ HX;JO[0
} \E(Negt7
//int [] counts = ps.executeBatch();⑶ _~l*p"PL<
conn.commit(); ;p/%)WW
}catch(Exception e){ $s2Y,0>I6
e.printStackTrace(); MO_-7,.y
} finally{ W>+/N4
try{ 0eGz|J*7
if(ps!=null) { ;?{N=x8
ps.clearParameters(); *%3%Zj,{
ps.close(); IL]Js W
ps=null; #j+0jFu
} qZV.~F+
}catch(SQLException e){} 0^0Q0A
DBUtils.closeConnection(conn); U#qs^f7R
} !Ojf9 6is
} (bX77 Xr
public long getLast(){ Smt&/~7D%
return lastExecuteTime; 6m~ N2^z
} ezq<)gJc
public void run(){ /8Sr(
long now = System.currentTimeMillis(); G1=/G
if ((now - lastExecuteTime) > executeSep) { =tKb7:KU
//System.out.print("lastExecuteTime:"+lastExecuteTime); (GeOD V?U
//System.out.print(" now:"+now+"\n"); ^$!H|
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); P^)J^{r
lastExecuteTime=now; Z\\'0yuY(
executeUpdate(); +Fk]hCL
} {o."T/?d'
else{ iI]E%H}
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); I+!?~]AUuq
} 5x2m]u
} N!{waPbPi
} ;8~tt I
//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 <Z>p1S
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类写好了,下面是在JSP中如下调用。 Fk-}2_=vi
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<% Ft[)m#Dj`
CountBean cb=new CountBean(); l0v]+>1i:
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); Ag82tDL[u
CountCache.add(cb); * NB:"1x
out.print(CountCache.list.size()+"<br>"); G-DvM6T
CountControl c=new CountControl(); 7 {n>0@_
c.run(); GyVRe]<>B
out.print(CountCache.list.size()+"<br>"); &gr)U3w
%>