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: q`|rS6
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CountBean.java J)EL<K$Z[
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/* _7;D0l
* CountData.java M2nWvU$
* 489xoP
* Created on 2007年1月1日, 下午4:44 G-TD9OgZ
* %l3f .
* To change this template, choose Tools | Options and locate the template under #l
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* the Source Creation and Management node. Right-click the template and choose [ <j4w
* Open. You can then make changes to the template in the Source Editor. wzF%R{;
*/ P&h]uNu
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package com.tot.count; HPXJRQBE
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/** X>i{288M3
* cAn_:^
* @author ;YZ'd"0v
*/ )~CNh5z6Y
public class CountBean {
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private String countType; *mz-g7
int countId; !E6QED"
/** Creates a new instance of CountData */ H@te!EE
public CountBean() {} i!*8@:VI
public void setCountType(String countTypes){ RBLOc$2
this.countType=countTypes; [ut[W9
} txiX1o!/L
public void setCountId(int countIds){ Cw l:
this.countId=countIds; \[d~O>k2
} `PT'Lakf;3
public String getCountType(){ >uxAti\
return countType; 3i#'osq
} 2;x+#D8
public int getCountId(){ tHEZuoi
return countId; (W.G&VSn)
} 4N5\sdi
} /@1pm/>ZaN
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CountCache.java VV/aec8
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/* 1/v#Z#3[
* CountCache.java V0G[f}tm'
* 3pe1"maP
* Created on 2007年1月1日, 下午5:01 p/HGI)'
* VHG}'r9KC%
* To change this template, choose Tools | Options and locate the template under A@eR~Kp
^
* the Source Creation and Management node. Right-click the template and choose 30O7u3Zrb
* Open. You can then make changes to the template in the Source Editor. *6G@8TIh
*/ "|BSGV!8
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package com.tot.count; T_d)1m fl
import java.util.*; iZ4"@G:,
/** Q)=2%X
* p||mR
* @author U_RWqKL
*/ |-HNHUF
public class CountCache { z 'V$)U$f
public static LinkedList list=new LinkedList(); F<^f6z8
/** Creates a new instance of CountCache */ QZ+G2$
public CountCache() {} /I:&P Pff
public static void add(CountBean cb){ o?^Rw*u0/
if(cb!=null){ ByacSN
list.add(cb); z3{Cp:Mn
} HP\5gLVXY
} 6),!sO?
} g""Ep
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CountControl.java V{fG~19
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/* TiR00#b
* CountThread.java . I."q
* OlgM7Vrl
* Created on 2007年1月1日, 下午4:57 m;0ZV%c*j
* h@TP=
* To change this template, choose Tools | Options and locate the template under G_M8? G0
* the Source Creation and Management node. Right-click the template and choose P-DW@drxF
* Open. You can then make changes to the template in the Source Editor. Tv9\`F[
*/ !Sl_qL
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package com.tot.count; '.jYu7
import tot.db.DBUtils; dK4w$~j{k
import java.sql.*;
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/** 99"8d^{z
* G E? \Vm
* @author `lrNH]B
*/ r]U8WM3r
public class CountControl{ w&e3#p
private static long lastExecuteTime=0;//上次更新时间 wB:<ICm
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 nX\mCO4T
/** Creates a new instance of CountThread */ l&5Tft
public CountControl() {} IG:2<G
public synchronized void executeUpdate(){ 13 %:3W(
Connection conn=null; ;/H/Gn+
PreparedStatement ps=null; rs,'vV-2\
try{ hZw8*H^tP
conn = DBUtils.getConnection(); }Syd*%BR[
conn.setAutoCommit(false); IZGRQmi"
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); //RD$e?h~
for(int i=0;i<CountCache.list.size();i++){ t*)!BZ
CountBean cb=(CountBean)CountCache.list.getFirst(); y.-Kqa~
CountCache.list.removeFirst(); c|K:oi,z
ps.setInt(1, cb.getCountId()); 2%*\XPt)
ps.executeUpdate();⑴ 2XEE/]^
//ps.addBatch();⑵ li{!Jp5]1b
} oArXP\#
//int [] counts = ps.executeBatch();⑶ j6j4M,UI43
conn.commit(); #. 71O#!
}catch(Exception e){ SE(c_ sX
e.printStackTrace(); Dy:r)\KX
} finally{ h6}rOchj
try{ ]]e>Jym
if(ps!=null) { xSDTO$U8%
ps.clearParameters(); wk{]eD%
ps.close(); LB[?kpy
ps=null; `xZ,*G7(*
} R}IuMMx
}catch(SQLException e){} Xq<_r^
DBUtils.closeConnection(conn); FlUO3rc|
} bkz/V/ Y
} +(W7hK4ip
public long getLast(){ ;rNX
return lastExecuteTime; c|Z6p{)V
} GB;_!69I
public void run(){ nB0KDt_
long now = System.currentTimeMillis(); Yh Ow0 x
if ((now - lastExecuteTime) > executeSep) { JcMl*k
//System.out.print("lastExecuteTime:"+lastExecuteTime); suYbD!`(
//System.out.print(" now:"+now+"\n"); G_zK .N
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); ZAn9A>5_
lastExecuteTime=now; *_P'> V#p
executeUpdate(); J#q^CWN3R
} ,gM:s}l!dJ
else{ YQWq*o^:
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); .8GXpt^U(
} "d/uyS$6
} y7R=zkd
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} gdg``U;)p
//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 z:
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类写好了,下面是在JSP中如下调用。 IVa6?f6H_
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<% '&2-{Y [!
CountBean cb=new CountBean(); 27}7
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cb.setCountId(Integer.parseInt(request.getParameter("cid"))); _g-0"a{-
CountCache.add(cb); WQ9Q:F2
out.print(CountCache.list.size()+"<br>"); n&DBMU
CountControl c=new CountControl(); EXwU{Hl
c.run(); j)#yyK{k2s
out.print(CountCache.list.size()+"<br>"); 7j29wvSp5
%>