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: 7:x%^J+
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CountBean.java )2T 1g~8
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/* =)}m4,LA
* CountData.java 'j>+eA>
* BH _y0[y
* Created on 2007年1月1日, 下午4:44 pE(\q+1<
* ^b=] =w
* To change this template, choose Tools | Options and locate the template under 5`CPaJT$
* the Source Creation and Management node. Right-click the template and choose yNVuSj
* Open. You can then make changes to the template in the Source Editor. :|/bEP]p/
*/ 5&]|p'"W\
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package com.tot.count; }Th":sin},
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/** (as'(+B
* ??tyz4$;
* @author
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*/ ]37k\O?vd
public class CountBean { t]1j4S"pm
private String countType; 6||zwwk'.
int countId; #|'&%n|Z
/** Creates a new instance of CountData */
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public CountBean() {} xo#&&/6
public void setCountType(String countTypes){ QA_SS'*
this.countType=countTypes; u=B_c A}:
} x 9}D2Ui
public void setCountId(int countIds){ H'68K8i0
this.countId=countIds; p] kpDx[9
} x
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public String getCountType(){ 1;E[Ml
return countType; MK"PCE5^i6
} zh7#[#>t
public int getCountId(){ f&=y\uP]
return countId; 1Y iUf
} NQS@i'W=g
} Pk444_"=
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CountCache.java q]Gym 7o
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/* Rz%
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* CountCache.java }m NP[L
* e;8>/G
* Created on 2007年1月1日, 下午5:01 ;EstUs3
* ;}),6R
* To change this template, choose Tools | Options and locate the template under pC,MiV$c"
* the Source Creation and Management node. Right-click the template and choose Gs$<r~Tg
* Open. You can then make changes to the template in the Source Editor. mlCw(i,
*/ 5P_%Vp`B2
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package com.tot.count; zRtaO'G(
import java.util.*; t6p}LNm(V
/** Di{T3~fqU
* bv$g$
* @author 5^'PjtW6
*/ I=)Hb?qT~
public class CountCache { F[/Bp>P7
public static LinkedList list=new LinkedList(); lV!ecJw$
/** Creates a new instance of CountCache */ WHxq-&=
public CountCache() {} /zZ$<mVG
public static void add(CountBean cb){ 9Mo(3M
if(cb!=null){ 'T@K$xL8
list.add(cb); *k'D%}N:
} 1GB$;0 W),
} Th,15H
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} oeKI9p13\
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CountControl.java ^44AE5TO
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/* $(v1q[ig
* CountThread.java B6~a `~"
* `9M:B&
* Created on 2007年1月1日, 下午4:57 +jD?h-]
* b*=eMcd
* To change this template, choose Tools | Options and locate the template under PY7j uS[+
* the Source Creation and Management node. Right-click the template and choose H&\IgD
* Open. You can then make changes to the template in the Source Editor. :NJb<%$
*/ QUd`({/@:
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package com.tot.count; tU7,nE>p
import tot.db.DBUtils; Rb=T'x'
import java.sql.*; VD+TJ` r
/** [O*5\&6
* \(Z'@5vC
* @author "o&_tB;O
*/ xsS/)R?
public class CountControl{ \y?Vou/
private static long lastExecuteTime=0;//上次更新时间 ,lSt}Lml
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 A `\2]t$z
/** Creates a new instance of CountThread */ HU]Yv+3
public CountControl() {} j>XM+>
public synchronized void executeUpdate(){ bnBnE[y<'
Connection conn=null; (UWP=L1
PreparedStatement ps=null; +r[u4?
try{ bTB/M=M
conn = DBUtils.getConnection(); xC;b<~zN
conn.setAutoCommit(false); @? 4-
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); K~"uZa^s
for(int i=0;i<CountCache.list.size();i++){ Q#NXJvI
CountBean cb=(CountBean)CountCache.list.getFirst(); +=#sam*i
CountCache.list.removeFirst(); KJc
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ps.setInt(1, cb.getCountId()); 9?<WRM3a>
ps.executeUpdate();⑴ =N,9#o6^
//ps.addBatch();⑵ qPsf`nI7
} YCod\} 3
//int [] counts = ps.executeBatch();⑶ >0kn&pe7#T
conn.commit(); `*nVLtT Y
}catch(Exception e){ xVHZZ?e
e.printStackTrace(); u 0KVp6`
} finally{ NT?Gl(
try{ %rVC3}
if(ps!=null) { Up?w>ly
ps.clearParameters(); d5&avL\
ps.close(); b%<-(o/
ps=null; bL\ab
} "PH}\Dl=
}catch(SQLException e){} &~oBJar
DBUtils.closeConnection(conn); d`9%:2qE
} +{Yd\{9
} 9[}L=n
public long getLast(){ ]pi"M3f_
return lastExecuteTime; n'a=@/
} igFz~
public void run(){ !-1UJqO
long now = System.currentTimeMillis(); $ )q?z.U
if ((now - lastExecuteTime) > executeSep) { &rs+x<
//System.out.print("lastExecuteTime:"+lastExecuteTime); s0,c4y
//System.out.print(" now:"+now+"\n"); t|q@~B
:
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); dH"wYMNL
lastExecuteTime=now; b^b@W^\hn
executeUpdate(); 0Q>f,}W%>
} P)x&9OHV
else{ M:V'vme)+
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); rhU]b $A
} RWM9cV5
} GZ.Xx
} 3>X]`Oj7y
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 kBZnR$Cl
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类写好了,下面是在JSP中如下调用。 KEF"`VTB@
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<% -_&"Q4FR;+
CountBean cb=new CountBean(); 5,
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); #(6^1S%
CountCache.add(cb); e=$p(
out.print(CountCache.list.size()+"<br>"); x=(y
CountControl c=new CountControl(); ]hY'A>4Uq
c.run(); ?;NC(Z,
out.print(CountCache.list.size()+"<br>"); apsR26\^
%>