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: gH:+$FA
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CountBean.java ]%ey rbU
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/* Y0xn}:%K
* CountData.java SI9PgC
* ?G<.W[3
* Created on 2007年1月1日, 下午4:44 49-wFF
* N-YCOSUu
* To change this template, choose Tools | Options and locate the template under \Y^GA;AMQQ
* the Source Creation and Management node. Right-click the template and choose "a=dx|
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* Open. You can then make changes to the template in the Source Editor. 6S&OE k
*/ DW>|'w %
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package com.tot.count; xV>sc;PEb
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/** rq![a};~
* 'tn-o
* @author UoOxGo
*/ g66x;2Q
public class CountBean { EWK?vs
private String countType; Zr|z!S?aSC
int countId; &h'NC%"v
/** Creates a new instance of CountData */ M~Ph/
public CountBean() {} MwTouEGGgA
public void setCountType(String countTypes){ P]<15l
this.countType=countTypes; DT[WO_=
} o|Kd\<rY
public void setCountId(int countIds){ {VT**o
this.countId=countIds; "] [u
} i<-a-Z+^
public String getCountType(){ 4;V;8a\A
return countType; >TG#
} 3_N1y
public int getCountId(){ p@[n(?duC.
return countId; bEB9J-
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} Q=h37]U+
} tKYg
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CountCache.java 3"LT ''
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/* v(~EO(n.
* CountCache.java d-'BT(@:
* jQ3&4>g j
* Created on 2007年1月1日, 下午5:01 K96N{"{iI%
* =?[:Nj636
* To change this template, choose Tools | Options and locate the template under UY^TTRrH
* the Source Creation and Management node. Right-click the template and choose =k##*%
* Open. You can then make changes to the template in the Source Editor. `*y%[J,I#
*/ rAh|r}R
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package com.tot.count; V>& 1;n
import java.util.*; 9v?rNJs
/** V<Co!2S
* cf%aOHYI*
* @author .$a|&P=S
*/ 7[:?VXQ
public class CountCache { lY[\eQ
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public static LinkedList list=new LinkedList(); yi*EE%
/** Creates a new instance of CountCache */ 3u/ GrsF
public CountCache() {} L b-xc]
public static void add(CountBean cb){ 5#mHWBGd7
if(cb!=null){ g1I8_!}~
list.add(cb); 2hY"bpGW
} V(;c#%I2
} dpcU`$kt
} ]sJjV
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CountControl.java 5h6-aQU[
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/* i4lB]k
* CountThread.java &n]]OPo
* <.:mp1,8V
* Created on 2007年1月1日, 下午4:57 *0Wkz'=U
* c3(0BSv
* To change this template, choose Tools | Options and locate the template under \-D[C+1(
* the Source Creation and Management node. Right-click the template and choose jJAr #|
* Open. You can then make changes to the template in the Source Editor. Z_s]2y1
*/ F%$lcQ04%
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package com.tot.count; `l
import tot.db.DBUtils; F&HvSt}l5
import java.sql.*; _mTNK^gB
/** >N"=10
* zvwv7JtB
* @author }ISR +./+
*/ vHN/~k#
public class CountControl{ \m(>Q
private static long lastExecuteTime=0;//上次更新时间 zz #IY'dwT
private static long executeSep=60000;//定义更新间隔时间,单位毫秒
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/** Creates a new instance of CountThread */ #>2cfZ`6'J
public CountControl() {} LBIEG_/m
public synchronized void executeUpdate(){ l $0w 9Z^
Connection conn=null; Rp
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PreparedStatement ps=null; lL&p?MUp
try{ <7o@7r'0
conn = DBUtils.getConnection(); c*",AZ>U
conn.setAutoCommit(false); c=<^pCa9t1
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); \6!s";=hQ
for(int i=0;i<CountCache.list.size();i++){ mh35S!I3I^
CountBean cb=(CountBean)CountCache.list.getFirst(); 5hfx2O)
CountCache.list.removeFirst(); J9P\D!
ps.setInt(1, cb.getCountId()); 4%7Oaf>9
ps.executeUpdate();⑴ 8#IEE|1
//ps.addBatch();⑵ 0yxwsBLy
} @B9#Hrc
//int [] counts = ps.executeBatch();⑶ o(D6
conn.commit(); M $zt;7P|
}catch(Exception e){ O@>{%u
e.printStackTrace(); Mo\nY5
} finally{ z8
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try{ kfq<M7y
if(ps!=null) { 06I(01M1
ps.clearParameters(); +1Pu29B0
ps.close(); zLg_0r*h1
ps=null; m}+_z^@j9
} W=4|ahk$
}catch(SQLException e){} Lbu,VX
DBUtils.closeConnection(conn); Vk%W4P"l
} !'-./LD")
} H%;pPkIi
public long getLast(){ Kr%`L/%
return lastExecuteTime; 'grb@+w(
} |T{ZDJ+
public void run(){ le2 v"Y
long now = System.currentTimeMillis(); X
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if ((now - lastExecuteTime) > executeSep) { Tvw(Sq};
//System.out.print("lastExecuteTime:"+lastExecuteTime); y2Vc[o(NP
//System.out.print(" now:"+now+"\n"); yppXecFJ
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); 2>.>q9J(
lastExecuteTime=now; l#a*w
executeUpdate(); 4g?qKoc
i
} ,&jjpeZP
else{ BG+X8t8\
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); =6BI[_0
} hroRDD
} Q`Ug tL
} uKo4nXVtp
//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 mWuhXY^Q
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类写好了,下面是在JSP中如下调用。 A&_v:z4y/
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<% 9 'IDbe{
CountBean cb=new CountBean(); ^@]yiED{g
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); #Q%0y^s
CountCache.add(cb); ~AR0 ,lak
out.print(CountCache.list.size()+"<br>"); Q#Xa]A-
CountControl c=new CountControl(); o+?Ko=vYw
c.run(); qGgdWDn`
out.print(CountCache.list.size()+"<br>"); 8\[qR_LV
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