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: v5S9h[gT
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CountBean.java 7amVnR1f
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/* B{j><uxl
* CountData.java &[-(=43@
* !Rl|o^Vw>{
* Created on 2007年1月1日, 下午4:44 El<*)
* h.>SVQzU
* To change this template, choose Tools | Options and locate the template under o2ggHZe/=@
* the Source Creation and Management node. Right-click the template and choose ,-y9P
* Open. You can then make changes to the template in the Source Editor. <(lA
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*/ `]eJF|"
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package com.tot.count; lWId
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/** F$?Ab\#B
* ~U]g;u
* @author U8Y%rFh1
*/ c}o 6Rm50
public class CountBean { .r<aPy$
private String countType; OT])t<TF6
int countId;
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/** Creates a new instance of CountData */ ^U_T<x8{
public CountBean() {} LW]fme<V?
public void setCountType(String countTypes){ :x\[aG9
this.countType=countTypes; =#G
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} @N>7+
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public void setCountId(int countIds){ u<BU4c/p
this.countId=countIds; SN{+ P k
} 'cs(gc0
public String getCountType(){ %F>~2g?$
return countType; S 5S\zTPIf
} RehmVkT
public int getCountId(){ !,Uo{@E)Y
return countId; n N<N~
} {[oNUzcd
} EjR(AqZY
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CountCache.java K|P0nJT
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/* Pp8S\%z~h
* CountCache.java aDbqh~7
* 1X?ro;
* Created on 2007年1月1日, 下午5:01 }e[ E
* &uNec(c
* To change this template, choose Tools | Options and locate the template under 7*5B
* the Source Creation and Management node. Right-click the template and choose @Po5AK3cy
* Open. You can then make changes to the template in the Source Editor. Lzh8-d=HQ
*/ 4era5=
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package com.tot.count; |`T(:ZKXZ2
import java.util.*; U: 9&0`k(
/** [RyVR
* /%T/@y
* @author 7d: ]o>
*/ MpCPY"WLL
public class CountCache { oB:7R^a
public static LinkedList list=new LinkedList(); E'QAsU8pP
/** Creates a new instance of CountCache */ Y <6|z3
public CountCache() {} *QC6zJ
public static void add(CountBean cb){ xVx s~p1
if(cb!=null){ \((iR>^|
list.add(cb); hY"eGaoF"
} `0d0T~
} dN{At-
} DzZF*ylQ5P
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CountControl.java Y)rK'OY'
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/* x5lVb$!G
* CountThread.java m}]{Y'i]R
* Za|7gt];l
* Created on 2007年1月1日, 下午4:57 _}l(i1o,/
* VI!
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* To change this template, choose Tools | Options and locate the template under Ua1&eCZi
* the Source Creation and Management node. Right-click the template and choose LRJX>+@
* Open. You can then make changes to the template in the Source Editor. BZeEZ2"
*/ V+gZjuN$
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package com.tot.count; CmU@8-1
import tot.db.DBUtils; V3,C5KKk&z
import java.sql.*; 6{2y$'m8
/** N*IroT3
* odP<S.
* @author e@'x7Zzh
*/ Jf^3nBZ
public class CountControl{ NLsF6BX/-
private static long lastExecuteTime=0;//上次更新时间 )vtbA=RH?
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 579Q&|L.
/** Creates a new instance of CountThread */ N8sT?
public CountControl() {} a*M|_&MH*
public synchronized void executeUpdate(){ q!z?Tn#!jd
Connection conn=null; N_%@_$3G]
PreparedStatement ps=null; }8O9WS
try{ 7[Us.V@
conn = DBUtils.getConnection(); ,EQ0""G!
conn.setAutoCommit(false); RXXHg
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); <&eJIz=
for(int i=0;i<CountCache.list.size();i++){ vn.5X
CountBean cb=(CountBean)CountCache.list.getFirst(); 6#=Iv X4
CountCache.list.removeFirst(); M"z=114
ps.setInt(1, cb.getCountId()); 1j2U,_-
ps.executeUpdate();⑴ wSR|uh
//ps.addBatch();⑵ o$@/@r
} {4+/0\
//int [] counts = ps.executeBatch();⑶ IADSWzQ@
conn.commit(); 5<Kt"5Z%7
}catch(Exception e){ 5OdsT-y
e.printStackTrace(); iwnGWGcuS
} finally{ b: (+d"S
try{ f1NHW|_j
if(ps!=null) { <:-4GJH=
ps.clearParameters(); l0&Fm:))k
ps.close(); `0upm%A
ps=null; Uz ;^R@
} Y%}&eN$r
}catch(SQLException e){} T"\d,ug5[
DBUtils.closeConnection(conn); ET[5`z
} +}jzge"
} jdG'sITv
public long getLast(){ qkfof{z
return lastExecuteTime; GW
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} #19O5
public void run(){ J>X@g;
long now = System.currentTimeMillis(); x& _Y( bHA
if ((now - lastExecuteTime) > executeSep) { 8jCho
//System.out.print("lastExecuteTime:"+lastExecuteTime); $mxG-'x%K
//System.out.print(" now:"+now+"\n"); B1X&O d
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); c@>ztQU*
lastExecuteTime=now; Vg62HZ |
executeUpdate(); .*NPoW4Kv
} J@_M%eN
else{ vU *: M8k
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); wQW`Er3w
} t|>P9lX@
} H[w';u[%
} G;gsDn1t
//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 shB3[W{}!)
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类写好了,下面是在JSP中如下调用。 nZiwR4kM
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<% *L?~
CountBean cb=new CountBean(); B\D)21Ik}%
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); aVr(*s;/
CountCache.add(cb); jR\pYRK
out.print(CountCache.list.size()+"<br>"); dr#%~I
CountControl c=new CountControl(); 9@qkj
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c.run(); (KO]>!t
out.print(CountCache.list.size()+"<br>"); +M.BMS2A<l
%>