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: `G{t<7[[;
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CountBean.java ZWW}r~d{
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/* #>NZN1
* CountData.java t$%}*@x7
* GUZi }a|=
* Created on 2007年1月1日, 下午4:44 ho<#i(
* nXW1 :
* To change this template, choose Tools | Options and locate the template under !9Xex?et
* the Source Creation and Management node. Right-click the template and choose c67!OHu mP
* Open. You can then make changes to the template in the Source Editor. cne[-E
*/ Kwau:_B
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package com.tot.count; (acRYv(
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/** uf3 gVS_h=
* Stx-(Kfn4
* @author .6(i5K
*/ l,8|E
public class CountBean { #r}c<?>Vw
private String countType; (P_+m#
int countId; AIo;\35
/** Creates a new instance of CountData */ RH'R6
public CountBean() {} J#nEGl|a
public void setCountType(String countTypes){ SjU6+|l
this.countType=countTypes; m8`A~
} 1 crjRbi
public void setCountId(int countIds){ Xb;`WE gC
this.countId=countIds; 6P$q7G
} ?!vW&KJZx
public String getCountType(){ .=D6<4#t
return countType; :v48y.Ij7s
} 1Pc'wfj
public int getCountId(){ 7%WI
return countId; O;tn5
} / nRaxzf'
} 9`b3=&i\
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CountCache.java 3M`J.>
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/* yK;I<8+>_
* CountCache.java X}
8U-N6)
* $S/ 8T
* Created on 2007年1月1日, 下午5:01 D':A-E
* *n\qV*|6bI
* To change this template, choose Tools | Options and locate the template under 'ZZ/:MvQa
* the Source Creation and Management node. Right-click the template and choose U)6JJv
* Open. You can then make changes to the template in the Source Editor. ]5CFL$_Q{
*/ dY^~^<{Lj
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package com.tot.count; &kt#p;/p?
import java.util.*; VI{1SIhfa
/** +!wc(N[(2
* xDS9gGr
* @author =X):Zi
*/ %0'f`P6
public class CountCache { oKiu6=
public static LinkedList list=new LinkedList(); &aU+6'+QXB
/** Creates a new instance of CountCache */ 8iB}a\]B
public CountCache() {} uNDkK o<M
public static void add(CountBean cb){ Z )I4U
if(cb!=null){ #B[>\D"*
list.add(cb); a1&^P1.
} lRq!|.C
} 7[PXZT
} Urr1K)
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CountControl.java UgJHSl
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/* |ipppE=
* CountThread.java _4w%U[GT,
* 'tj4 ;+xf^
* Created on 2007年1月1日, 下午4:57 IG\\RYr
* /e,lD)
* To change this template, choose Tools | Options and locate the template under Hqk2W*UTl
* the Source Creation and Management node. Right-click the template and choose )sr]}S0
* Open. You can then make changes to the template in the Source Editor. Qy%/+9L
*/ :A[/;|&
'S\H% -
package com.tot.count; 'lF|F+8
import tot.db.DBUtils; 6 s/O\A
import java.sql.*; 3h>Ji1vV
/** - =Hr|AhE
* +(
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* @author Phczf
*/ wKN9HT
public class CountControl{ 1*"Uc!7.%
private static long lastExecuteTime=0;//上次更新时间 {_JLmyaerZ
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 &+sN=J.x
/** Creates a new instance of CountThread */ &W%TY:Da|
public CountControl() {} _nt%&f
public synchronized void executeUpdate(){ !E8JpE|z#
Connection conn=null; $}829<gh7
PreparedStatement ps=null; :d;5Q\C`
try{ 2t'&7>Ys{
conn = DBUtils.getConnection(); :>;#/<3{
conn.setAutoCommit(false); @QEVl
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); &nss[w$%C
for(int i=0;i<CountCache.list.size();i++){ gVc[`(@h
CountBean cb=(CountBean)CountCache.list.getFirst(); 0qv)'[O
CountCache.list.removeFirst(); gDrqs>8
ps.setInt(1, cb.getCountId()); Lv"83$^S9
ps.executeUpdate();⑴ !}%giF$-
//ps.addBatch();⑵ [
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} Ptg73Gm&R
//int [] counts = ps.executeBatch();⑶ 'nul{RE*
conn.commit(); UkC\[$-"\
}catch(Exception e){ cjL!$OE6
e.printStackTrace(); ;%)i/MGEB
} finally{ XpGom;z^c
try{ [O3R(`<e5
if(ps!=null) { F^f]*MhT"
ps.clearParameters(); (0S"ZT
ps.close(); lZ|Ao0(
ps=null; 5"sF#Y&
} ifkA3]
}catch(SQLException e){} 0-FbV,:;
DBUtils.closeConnection(conn); +RM3EvglDQ
} cGDA0#r
} $T6<9cB@
public long getLast(){ >&TktQO_T
return lastExecuteTime; T'X Rl@
} -%A6eRShk
public void run(){ $]vR ,E
long now = System.currentTimeMillis(); {>:2Ff]O:
if ((now - lastExecuteTime) > executeSep) { cIX59y#7
//System.out.print("lastExecuteTime:"+lastExecuteTime); :p{iBDA
//System.out.print(" now:"+now+"\n"); f,$CiZ"
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); `4o;Lz~
lastExecuteTime=now; &45.*l|mo
executeUpdate(); 9H<:\-:
} o8" [6Ys
else{ c}Qc2D3*
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); Zqao4
} ecb[m2z
} ,W#y7t
} /xmd]XM=_
//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 dZm{?\^_
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类写好了,下面是在JSP中如下调用。 1ayxE(vMcX
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<% :+YFO.7
CountBean cb=new CountBean(); b`2~
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); pyN PdEy
CountCache.add(cb); Deam%)bXM]
out.print(CountCache.list.size()+"<br>"); b~|B(lL6Xm
CountControl c=new CountControl(); {kC]x2 U
c.run(); j>6{PDaT
out.print(CountCache.list.size()+"<br>"); H;^6%HV1
%>