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: 1}tZ,w>
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CountBean.java 4wX{ N
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/* XPd>DH(Yc
* CountData.java `i8osX[ &p
* eU1= :n&&\
* Created on 2007年1月1日, 下午4:44 Pqo_+fL+
* Op,Ce4A
* To change this template, choose Tools | Options and locate the template under vpFN{UfD
* the Source Creation and Management node. Right-click the template and choose j,80EhZ
* Open. You can then make changes to the template in the Source Editor. OwwH 45
*/ \bCm]wR
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package com.tot.count; Vg#s
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/** $B7<1{<=W
* AEX]_1TG
* @author #57nm]?
*/ `mQY%p|
public class CountBean { muQH!Q
private String countType; `x lsvK>
int countId; Z=sy~6m+v
/** Creates a new instance of CountData */ $R2T)
public CountBean() {} im>Sxu@
public void setCountType(String countTypes){ e,={!P"f
this.countType=countTypes; J|sX{/WT
} WiH%URFB
public void setCountId(int countIds){ a^<
this.countId=countIds; ({yuwH?tH
} n <6}
public String getCountType(){ LU_@8i:
return countType; ::g"dRS<v
} `~WxMY0M
public int getCountId(){ j?i Ur2
return countId; 6i(V+
} MX|CL{H
} 5`{ +y]
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CountCache.java U
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/* (sW:^0 p
* CountCache.java ;DL|%-%;$r
* b,Ed}Ir
* Created on 2007年1月1日, 下午5:01 }9R45h}{<
* nZfTK>)A0
* To change this template, choose Tools | Options and locate the template under 6dV@.(][a
* the Source Creation and Management node. Right-click the template and choose xrA(#\}f$
* Open. You can then make changes to the template in the Source Editor. KZ6}),p
*/ j1N1c~2
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package com.tot.count; nSz Fs(]f
import java.util.*; V5i_\A
/** U>(5J,G
* GIWgfE?
* @author W:aAe%S
*/ lN,b@;
public class CountCache { U;?%rM6
public static LinkedList list=new LinkedList(); LbJtU!
/** Creates a new instance of CountCache */ b+'G^!JR
public CountCache() {} &vj+3<2
public static void add(CountBean cb){ qlIC{:E0
if(cb!=null){ G&0&*mp
list.add(cb); U)zd~ug?m
} Yi{[llru
} 7,!Mmu
} =jkC]0qx
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CountControl.java MnO,Cd6{%d
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/* h.%VWsAO7
* CountThread.java weT33O"!1
* HyiuU`
* Created on 2007年1月1日, 下午4:57 nUQcoSY#
* J{@gp,&e
* To change this template, choose Tools | Options and locate the template under X;w1@4!
* the Source Creation and Management node. Right-click the template and choose ?#qA>:2,
* Open. You can then make changes to the template in the Source Editor. NO
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*/ G`R Ed-Z[
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package com.tot.count; s^^X.z ,
import tot.db.DBUtils; F]
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import java.sql.*; DGC-`z
/** ; QR|v
* 022YuqL<v
* @author gu/eC
*/ bS&'oWy*B
public class CountControl{ ;} gvBI2e
private static long lastExecuteTime=0;//上次更新时间 ,YSQog
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 'P)xY-15
/** Creates a new instance of CountThread */ }Tu_?b`RUm
public CountControl() {} nqBZp N^
public synchronized void executeUpdate(){ bFVz ;
Connection conn=null; -]Z!_[MlDF
PreparedStatement ps=null; KA`1IW;
try{ dY~3YD[
conn = DBUtils.getConnection(); ba%[!
conn.setAutoCommit(false); elWN-~
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); 6[69|&
for(int i=0;i<CountCache.list.size();i++){ enF.}fo]
CountBean cb=(CountBean)CountCache.list.getFirst(); Z"lL=0rY/
CountCache.list.removeFirst(); hEl)BRJ
ps.setInt(1, cb.getCountId()); e[ i&2mM
ps.executeUpdate();⑴
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//ps.addBatch();⑵ go]d+lhFB
} Jb6rEV>
//int [] counts = ps.executeBatch();⑶ G 8uX[-L1
conn.commit(); 8.o[K
}catch(Exception e){ zf$OC}|\w
e.printStackTrace(); `tVBV:4\
} finally{ 7V 4iPx
try{ a,d\<mx
if(ps!=null) { 1ScfX\F=
ps.clearParameters(); BNyDEFd
ps.close(); nv{ou[vQ
ps=null; CUnZ}@?d
} bC$n+G>6k
}catch(SQLException e){} L
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DBUtils.closeConnection(conn); |O+R%'z'<
} XC?H
} jS5e"LMIq
public long getLast(){ J%aW^+O
return lastExecuteTime; ).9-=P HlX
} ;)83tx
/
public void run(){ 3Nr8H.u&q
long now = System.currentTimeMillis(); k|BY 7C
if ((now - lastExecuteTime) > executeSep) { Xvi{A]V
//System.out.print("lastExecuteTime:"+lastExecuteTime); 56>Zqtp*
//System.out.print(" now:"+now+"\n"); ,G"?fQ7z R
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); m]Z+u e
lastExecuteTime=now; &'WgBjP
executeUpdate(); *B#OLx
} E"#<I*b
else{ =WyAOgy}
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); /#
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} 5;`([oX|_
} ?TMo6SU
} t82Bp[t
//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 IhM-a
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类写好了,下面是在JSP中如下调用。 S&_ZQLiQ$
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<% cn<9!2a
CountBean cb=new CountBean(); `WWf?g
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); 4yQ4lU,r
CountCache.add(cb); W;~^3Hz6
out.print(CountCache.list.size()+"<br>"); %- %/3
CountControl c=new CountControl(); \Vm{5[ :SA
c.run(); xdYjl.f
out.print(CountCache.list.size()+"<br>"); QdUl-(
%>