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: p0YTZS ]h
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CountBean.java 1Q;`<=
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/* SoY&R=
* CountData.java Ia"bP` L
* V+K.'
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* Created on 2007年1月1日, 下午4:44 ,[hJi3xM
* {DO9{96w4
* To change this template, choose Tools | Options and locate the template under 0UB'6wRVo
* the Source Creation and Management node. Right-click the template and choose NAocmbfNz
* Open. You can then make changes to the template in the Source Editor. -jw=Iyv
*/ "7
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package com.tot.count; XF$C)id2p
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/** BPOWo8TqD^
* &]c9}Ic
* @author dCyQC A[
*/ UX9o
public class CountBean { nBj7 Q!lW
private String countType; MU^Z*r
int countId; <z4!m/f[(
/** Creates a new instance of CountData */ *ZEs5`x
public CountBean() {} pV+;/y_
public void setCountType(String countTypes){ t2$:*PvE
this.countType=countTypes; 3G&1. 8
} 8UZEC-K
public void setCountId(int countIds){ Te/)[I'Tn
this.countId=countIds; nC Z
} Fy@D&j
public String getCountType(){ %~[F^
return countType; -
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} OWkK]O
public int getCountId(){ {gn[
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return countId; [6tQv<}^
} @'y"D
} $7*Ml)H!9
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CountCache.java m1hf[cg
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/* }bTMeCgI
* CountCache.java J{ Vl2P?@
* #75;%a8
* Created on 2007年1月1日, 下午5:01 Mf63 59
* tpctz~ .
* To change this template, choose Tools | Options and locate the template under oAx0$]+%V)
* the Source Creation and Management node. Right-click the template and choose WQ]pg
"
* Open. You can then make changes to the template in the Source Editor. ] ge-b\
*/ N!3f1d7RQ
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package com.tot.count; HTG;'$H^
import java.util.*; /P%:u0fX,
/** dd+).*
* *%e#)sn*
* @author -d~'tti
*/ >4E,_ `3N
public class CountCache { z,EOyi
public static LinkedList list=new LinkedList(); !]nCeo
/** Creates a new instance of CountCache */ hg~fFj3ST
public CountCache() {} Kna'5L5"
public static void add(CountBean cb){ J @fE")
if(cb!=null){ 4SrK]+|
list.add(cb); k|D!0^HE[
} VGq]id{*$
} .wSAysiQ|P
} v>5F[0gE
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CountControl.java 1d"P) 3dQ
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/* '9gI=/29D
* CountThread.java 9lxT5Wg
* |<0@RCgM
* Created on 2007年1月1日, 下午4:57 #rwR)9iC0
* *GhRU5
* To change this template, choose Tools | Options and locate the template under BTyVfq
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* the Source Creation and Management node. Right-click the template and choose `<n:D`{dZ
* Open. You can then make changes to the template in the Source Editor. [C6?:'}FA
*/ \zUsHK?L"t
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package com.tot.count; ){:aGGtko
import tot.db.DBUtils; As`^Ku&
import java.sql.*; DvCt^O*
/** /WfxI>v
* I'C,'
* @author :Eyv= =
*/ 7w*&Yg]
public class CountControl{ :S12=sFl$
private static long lastExecuteTime=0;//上次更新时间 ?+\,a+46P_
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 7fqYSMHR
/** Creates a new instance of CountThread */ nz\fN?q
public CountControl() {} rWXW}Yg
public synchronized void executeUpdate(){ De_</1Au!2
Connection conn=null; as4NvZ@+r
PreparedStatement ps=null; %-Z~f~<?
try{ w$4Lu"N:
conn = DBUtils.getConnection(); O|~'-^
conn.setAutoCommit(false); !Xi>{nV
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); d#Ajb
for(int i=0;i<CountCache.list.size();i++){ ]N_^{k,
CountBean cb=(CountBean)CountCache.list.getFirst(); vp@+wh]#
CountCache.list.removeFirst(); =*Xf(mh c
ps.setInt(1, cb.getCountId()); v3Yj2LSqx
ps.executeUpdate();⑴ bB-v ar
//ps.addBatch();⑵ 3#[I_
} MV}]i@V
//int [] counts = ps.executeBatch();⑶ Bl];^W^P
conn.commit(); (&,R1dLo
}catch(Exception e){ $NHWg(/R@
e.printStackTrace(); pt#[.n#f
} finally{ |5Pbc&mH8A
try{ ?xZmm%JF
if(ps!=null) { }q W aE
ps.clearParameters(); VHCzlg
ps.close(); sIsu >eL
ps=null; KT71%?P
} /p0LtUMu
}catch(SQLException e){} us%RQ8=k
DBUtils.closeConnection(conn); m=B0!Z1xx
} 9K<a}QJP
} FOi`TZ8
public long getLast(){ |$2N$6\SP
return lastExecuteTime; J
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} S45>f(!
public void run(){ 5i#w:O\cz
long now = System.currentTimeMillis(); ^^l"brPa
if ((now - lastExecuteTime) > executeSep) { h+D=/:B
//System.out.print("lastExecuteTime:"+lastExecuteTime); YWrY{6M
//System.out.print(" now:"+now+"\n"); .`N`M9
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); {1|7N
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lastExecuteTime=now; ZF(=^.gc
executeUpdate(); {C6;$#7P
} W2h[NimU
else{ l$_rA~Mo
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); cV,Dl`1r
} Po.BcytM
} \r,.hUp
} &Ld8Z9IeFp
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 M) XQi/
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类写好了,下面是在JSP中如下调用。
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<% J6D$ i+
CountBean cb=new CountBean(); -U[`pUY?f
cb.setCountId(Integer.parseInt(request.getParameter("cid")));
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CountCache.add(cb); \'Kj.EO{?$
out.print(CountCache.list.size()+"<br>"); $#3<rcOq
CountControl c=new CountControl(); z|)1l`
c.run(); }#5roNH~Z
out.print(CountCache.list.size()+"<br>"); C/XyDbH
%>