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: ntZ~m
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CountBean.java =+\$e1Mb*
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/* AOAO8%|I
* CountData.java j_V/GnEQ
* kP?_kMOx
* Created on 2007年1月1日, 下午4:44 qlvwK&W<QM
* TL@mM
* To change this template, choose Tools | Options and locate the template under }^ ,q#'
* the Source Creation and Management node. Right-click the template and choose =JxFp,
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* Open. You can then make changes to the template in the Source Editor. O"iak
*/ MyFCJJ/
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package com.tot.count; wPgDy
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/** mrqaM2,(I
* V:>`*tlh
* @author d' OGVN
*/ USFg_sO
public class CountBean { 8)?_{
private String countType; #N9d$[R*
int countId; d- kZt@DL=
/** Creates a new instance of CountData */ OpUA{P
public CountBean() {} lQ$+JX;n(y
public void setCountType(String countTypes){ Tyd
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this.countType=countTypes; t}~UYG(h~
} G
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public void setCountId(int countIds){ Ld~ q1*7J
this.countId=countIds; ?BsH{QRYQ
} .1{l[[= W
public String getCountType(){ ZB0+GG\
return countType; S<pkc8
} 2vvh|?M
public int getCountId(){ C`EY5"N r
return countId; P5P<"
} tR;{.
} R\y'_S=#a
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CountCache.java [xf$VkjuF
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/* (
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* CountCache.java ,5.
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* U{HML|
* Created on 2007年1月1日, 下午5:01 9rS,?
* u#3)p
* To change this template, choose Tools | Options and locate the template under A Iv<f9*.:
* the Source Creation and Management node. Right-click the template and choose {G%3*=?,j
* Open. You can then make changes to the template in the Source Editor. ?Q?598MC
*/ xEC2@J
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package com.tot.count; H `5Ct
import java.util.*; &~ y{'zoL
/** fp tIc#4
* ,2_w=<hq
* @author 8$m1eQ`{
*/ XR+rT
public class CountCache { J^h'9iQpi
public static LinkedList list=new LinkedList(); :cdQ(O.m
/** Creates a new instance of CountCache */ +N8aq<l
public CountCache() {} vzcz<i )
public static void add(CountBean cb){ Uuz?8/w}#
if(cb!=null){ -f 4>MG
list.add(cb); !xymoiArp
} L20rv:W$h
} -$9~xX
} yfC2^#9 Zu
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CountControl.java RAwk7F3qn
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/* NnP.k7m)
* CountThread.java |
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* pND48 g;
* Created on 2007年1月1日, 下午4:57 )vQNiik#
* 71*>L}H
* To change this template, choose Tools | Options and locate the template under PF67z]<o
* the Source Creation and Management node. Right-click the template and choose v4C3uNW
* Open. You can then make changes to the template in the Source Editor. ee^4KKsh\
*/ m#;.yR
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package com.tot.count; 7JS#a=D#
import tot.db.DBUtils; &urb!tQ>&
import java.sql.*; 7PA=)a\
/** "*t6t4/Q
* A6Q c;v+
* @author KX=/B=3~
*/ H>Ks6V)RL4
public class CountControl{ hg4J2m
private static long lastExecuteTime=0;//上次更新时间 V_lGj
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 cCk1'D|X[e
/** Creates a new instance of CountThread */ hR0]8l|
public CountControl() {} r.?+gW!C
public synchronized void executeUpdate(){ A]#_"fayo
Connection conn=null; }H; ]k-)
PreparedStatement ps=null; XHZLWh"gS
try{ 8;0^'Qr8
conn = DBUtils.getConnection(); f}%sO
conn.setAutoCommit(false); H(?e&Qkg
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); O'fc/cvh='
for(int i=0;i<CountCache.list.size();i++){ M&OsRrq
CountBean cb=(CountBean)CountCache.list.getFirst(); pLPd[a
CountCache.list.removeFirst(); Yx!n*+ :J
ps.setInt(1, cb.getCountId()); |veBq0U
ps.executeUpdate();⑴ dX0x
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//ps.addBatch();⑵ 0S_Ra+e
} 418gcg6)
//int [] counts = ps.executeBatch();⑶ -CwWs~!
conn.commit(); h~:H?pj3g
}catch(Exception e){ ah>Dqb*
e.printStackTrace(); 9T/<x-FD
} finally{ sZT VM9<)
try{ il7!}
if(ps!=null) { %![4d;Z%x
ps.clearParameters(); @YsL*zw
ps.close(); 4 #G3ew
ps=null; [XxA.S)x3
} ^&HI+M
}catch(SQLException e){} ,rXW`7!2
DBUtils.closeConnection(conn); oR7 7`
} u$\Tg3du2
} =O;eY ?
public long getLast(){ >H8^0n)?
return lastExecuteTime; 4@gl4&<h
} >|(WS.n 3C
public void run(){ {8_:4`YZ
long now = System.currentTimeMillis(); ID&zY;f
if ((now - lastExecuteTime) > executeSep) { X=\x&Wt
//System.out.print("lastExecuteTime:"+lastExecuteTime); ~;` fC|)
//System.out.print(" now:"+now+"\n"); f&f[La
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); wH#Lb@cfZ0
lastExecuteTime=now; JLt{f=`%F
executeUpdate(); L-SdQTx_
} ]2g5Ka[>w
else{ 3EO#EYAHiM
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); Q:rT 9&G
} :K?iNZqWN6
} S`fu+^cv
} []!tT-Gzy
//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 - f+CyhR"*
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类写好了,下面是在JSP中如下调用。 uLF\K+cz
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<% N
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CountBean cb=new CountBean(); r*xq(\v
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); 9
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CountCache.add(cb); /]P%b K6B
out.print(CountCache.list.size()+"<br>"); zC[i <'h!T
CountControl c=new CountControl(); ^BQ>vI'.4
c.run(); >Y44{D\`
out.print(CountCache.list.size()+"<br>"); zv>ZrFl*
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