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: CsW*E,|xyP
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CountBean.java #e(P~'A0
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/* ZHW|P
* CountData.java *q+z5G;O
* D"+xF&
* Created on 2007年1月1日, 下午4:44 Q7@
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* <aEY=IF4
* To change this template, choose Tools | Options and locate the template under oB]
* the Source Creation and Management node. Right-click the template and choose _9Y7.5
* Open. You can then make changes to the template in the Source Editor. B;mt11M
*/ @(Y+W2Iyy+
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package com.tot.count; RB `<Zw
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/** C`>|D [
* VLfE3i4Vwl
* @author <j$n7#qk
*/ .j_YVYu1&
public class CountBean { ZsikI@?
private String countType; iv]*HE
int countId; *C n `pfO
/** Creates a new instance of CountData */ jM DG
public CountBean() {} wa}\bNKQk
public void setCountType(String countTypes){ om'DaG`A
this.countType=countTypes; +:fr(s!OE
} ??.9`3CYo
public void setCountId(int countIds){ 7Yrp#u1!
this.countId=countIds; H3Z"u
} _/zK^S)
public String getCountType(){ 'dTg\
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return countType; .ko}m{
} m?=9j~F*
public int getCountId(){ B)cVbjTn
return countId; N#? Ohz
} ;wkoQ8FD9
} r]+N(&q
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CountCache.java =2yg:D
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/* X#!oG)or
* CountCache.java 47 _";g@X
* qf2;yRc&
* Created on 2007年1月1日, 下午5:01 'WW['
* .^J7^Ky,
* To change this template, choose Tools | Options and locate the template under d5ivtK?
* the Source Creation and Management node. Right-click the template and choose j*aYh^
* Open. You can then make changes to the template in the Source Editor. 7JI&tlR4\c
*/ E5}wR(i,4
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package com.tot.count; NFQR
import java.util.*; "Lp"o
/** =Nj58 l
* L?c7M}vV
* @author ve|`I=?2
*/ H _%yh,L
public class CountCache { VD*xhuy$k
public static LinkedList list=new LinkedList(); M!ra3Y
/** Creates a new instance of CountCache */ ix=H=U]Q{
public CountCache() {} (YJ]}J^
public static void add(CountBean cb){ ORo +=2
if(cb!=null){ ADa'(#+6
list.add(cb); =_/,C
} Rr'^l]
} /:j9#kj
} 8v)PDO~D}A
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CountControl.java -bHfo%"^TT
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/* q3s
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* CountThread.java t,2Q~ied=
* faVR %
* Created on 2007年1月1日, 下午4:57 j`9+pI
* MFyMo
* To change this template, choose Tools | Options and locate the template under z!={d1u#T
* the Source Creation and Management node. Right-click the template and choose @fH?y Z=>
* Open. You can then make changes to the template in the Source Editor. kM`!'0kt
*/ !y>MchNv
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package com.tot.count; {|jG_
import tot.db.DBUtils; z mxrz[
import java.sql.*; !1H\*VM"
/** cO#e
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* 96.A8o
* @author W_zAAIY_Y
*/ _/)?GXwLn
public class CountControl{ UJ'}p&E
private static long lastExecuteTime=0;//上次更新时间 H...!c1M@
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 kXq*Jq
/** Creates a new instance of CountThread */ ^'|\8
public CountControl() {} VvO/
public synchronized void executeUpdate(){ -k19BDJ,W
Connection conn=null; +P~E54
PreparedStatement ps=null; +C{ %pF
try{ [akyCb
conn = DBUtils.getConnection(); z5CWgN
conn.setAutoCommit(false); q?=eD^]
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); #<7ajmr
for(int i=0;i<CountCache.list.size();i++){ %`c?cB
CountBean cb=(CountBean)CountCache.list.getFirst(); ( /cW
CountCache.list.removeFirst(); ZR3x;$I~4
ps.setInt(1, cb.getCountId()); #0HF7C3
ps.executeUpdate();⑴ ,'CDKzY
//ps.addBatch();⑵ =~&Fq$$
} BW>f@;egg
//int [] counts = ps.executeBatch();⑶
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conn.commit(); uxq!kF'Ls
}catch(Exception e){ $h Isab_
e.printStackTrace(); Z' 0Gd@/
} finally{ I499Rrw#E
try{ 'y#kRC=G:
if(ps!=null) { /#PEEN
ps.clearParameters(); kMS[
ps.close(); VK+#!!Ha
ps=null; z^/aJ@gQ
} w@Pc7$EP
}catch(SQLException e){} 5@+8*Fdk
DBUtils.closeConnection(conn); UN&b]vg
} W`C&$v#
} a$c7d~p$I
public long getLast(){ ^ ,Bxq^'D
return lastExecuteTime; &/7AW(?
} "jVMk
public void run(){ T
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long now = System.currentTimeMillis(); P]Z}%
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if ((now - lastExecuteTime) > executeSep) { vXnTPjbE
//System.out.print("lastExecuteTime:"+lastExecuteTime); ;X u&['
//System.out.print(" now:"+now+"\n"); )T6+}
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); ,/\%-u?
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lastExecuteTime=now; |5}{4k~9J
executeUpdate(); a4
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} 0;Y_@UVj
else{ LB1.N!q1
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); m7 !Fb
} Q:]F* p2
} 1anV!&a<K(
} {Ex0mw)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 n>X
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类写好了,下面是在JSP中如下调用。 Llf>C,)
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<% snTj!rV/_
CountBean cb=new CountBean(); '3wte9E/
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); v=:RxjEx
CountCache.add(cb); R
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out.print(CountCache.list.size()+"<br>"); l_LfV ON
CountControl c=new CountControl(); AA}M"8~2
c.run(); %@U<|9 %ua
out.print(CountCache.list.size()+"<br>"); S8" h9|
%>