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: 8*sP
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CountBean.java `jT1R!$3F
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/* H,)2Ou-Wn
* CountData.java ~Dj_N$_+9
* CMfR&G,)
* Created on 2007年1月1日, 下午4:44 {WuUzq`
* ~./M5P!\
* To change this template, choose Tools | Options and locate the template under dLw,dg
* the Source Creation and Management node. Right-click the template and choose Zv8G[(
* Open. You can then make changes to the template in the Source Editor. %)L|7v<
*/ R-5e9vyS
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package com.tot.count; -l$-\(,M`#
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/** *%QTv3{
* okD7!)cr=
* @author 88+J(^y>
*/ lLZ?&z$
public class CountBean { tSq`_[@
private String countType;
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int countId; )%9P ;/
/** Creates a new instance of CountData */ -;t]e6[
public CountBean() {} ~'/_q4
public void setCountType(String countTypes){ d+g+{p>?
this.countType=countTypes; D4ud|$s1
} lISu[{b?
public void setCountId(int countIds){ /qO?)p3gk
this.countId=countIds; g}'(V>(
} &;oWmmvz{
public String getCountType(){ lof}isOz
return countType; }P"JP[#E\
} b+mh9q'5E
public int getCountId(){ T\o!^|8
return countId; =j !Ruy1
} +vCW${U
} (
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CountCache.java 3}X; WE `
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/* 7I<] ;j
* CountCache.java F#$[jh$
* ejC== Fkc
* Created on 2007年1月1日, 下午5:01 N;d@)h(N!
* *27*&&=)H
* To change this template, choose Tools | Options and locate the template under m'suAj0
* the Source Creation and Management node. Right-click the template and choose WjvD C"
* Open. You can then make changes to the template in the Source Editor. gDjs:]/YR
*/ ,-{2ai_
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package com.tot.count; 7nL3+Pq
import java.util.*; X?Mc"M
/** bol#[_~
* ]o\y(!
* @author YPqp#X*
*/ rocG;$[
public class CountCache { : $>TeCm
public static LinkedList list=new LinkedList();
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/** Creates a new instance of CountCache */ M/mUY
public CountCache() {} A1(=7ZKz
public static void add(CountBean cb){ T'nQj<dBt:
if(cb!=null){ naoH685R4
list.add(cb); h_:|H8t;w
} 1V37%
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} &r
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} $zuemjW3p
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CountControl.java GP\Pk/E
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/* #D&]5"0cX
* CountThread.java D#n^U
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* )pAN_e"
* Created on 2007年1月1日, 下午4:57 yPqZ ,
* 9@."Y>1G
* To change this template, choose Tools | Options and locate the template under +aWI"d--h
* the Source Creation and Management node. Right-click the template and choose uk~4R@=&H
* Open. You can then make changes to the template in the Source Editor. ;/8oP ;X2
*/ __,1;=
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package com.tot.count; +B#3!
import tot.db.DBUtils; @fWmz,Ngl
import java.sql.*; UR&Uwa&.
/** #c ndq[H
* 9ZEF%&58Y
* @author O8N\
*/ &[hq !v
public class CountControl{ 1>SCY_Cv
private static long lastExecuteTime=0;//上次更新时间 ~"+Fp&[9f
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 *M_Gu{xc
/** Creates a new instance of CountThread */ 1MCHwX3/
public CountControl() {} j&.MT@
public synchronized void executeUpdate(){ FaNH+LPe
Connection conn=null; )TBG-<wt
PreparedStatement ps=null; {^xp?zpV
try{ XHu2G t_
conn = DBUtils.getConnection(); >}*iQq
conn.setAutoCommit(false); pGy(JvMw"
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); u8Au `
for(int i=0;i<CountCache.list.size();i++){ 5Q.bwl :
CountBean cb=(CountBean)CountCache.list.getFirst(); ^rc!X]C9
CountCache.list.removeFirst(); U>z8gdzu
ps.setInt(1, cb.getCountId()); pA*cF!tq7
ps.executeUpdate();⑴ /f9jLY+
//ps.addBatch();⑵ \Om<
FH}
} 6uYCU|JsU
//int [] counts = ps.executeBatch();⑶ O0{M3-
conn.commit(); $:%?-xy(
}catch(Exception e){ ?[\(i)]
e.printStackTrace(); %<oey%ue
} finally{ 9LkP*$2"M<
try{ k@eU #c5c
if(ps!=null) { Cr,UP8MO
ps.clearParameters(); ,?+rM ;
ps.close(); "mnWqRpX
ps=null; F(8>"(C
} dE+xU(\,w
}catch(SQLException e){} Syn>;FX
DBUtils.closeConnection(conn); 8}0W_C U,
} !Q`GA<ikv
} J>P{8Aw
public long getLast(){ r`|/qP:T[
return lastExecuteTime; vnXa4\Vdy
} PX3rHKK{
public void run(){ .VVY]>bJg@
long now = System.currentTimeMillis(); {ZH9W
if ((now - lastExecuteTime) > executeSep) { %p}_4+[;
//System.out.print("lastExecuteTime:"+lastExecuteTime); Dq!Vo ;s2
//System.out.print(" now:"+now+"\n"); -i@1sNx&'
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); 0)V<)"i
lastExecuteTime=now;
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executeUpdate(); ldo7}<s
} xS` %3+|
else{ bmEo5f~C!
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); {|%N
} N9D<wAK##)
} A-O@e
e
} U3 e3
//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 *f:^6h
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类写好了,下面是在JSP中如下调用。 &UUIiQm~
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<% F7`3,SzHp
CountBean cb=new CountBean(); #;Y JR9VN
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); :0.Z/s -
CountCache.add(cb); adh=Kp e!w
out.print(CountCache.list.size()+"<br>"); /a\6&Eb
CountControl c=new CountControl(); [0D( PV(n
c.run(); rS>JzbWa
out.print(CountCache.list.size()+"<br>"); #J]u3*Tn|
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