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:dHC,fO
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CountBean.java W#KpPDgZE
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/* *MJX?
* CountData.java _59huC.
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* Created on 2007年1月1日, 下午4:44 LL2=& VK
* 8g&?
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* To change this template, choose Tools | Options and locate the template under -amBB7g
* the Source Creation and Management node. Right-click the template and choose Zrvz;p@~
* Open. You can then make changes to the template in the Source Editor. !q9+9 *6
*/ 2
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package com.tot.count; ~ vJ,`?
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/** c2&q*]?l;
* lEhk'/~
* @author R $&o*K`?
*/ K Pt5=a
public class CountBean { byTh/ H
private String countType; Olh<,p+x
int countId; i(iXD
/** Creates a new instance of CountData */ "f "6]y
public CountBean() {} 0URji~?|x
public void setCountType(String countTypes){ c&AygqN
this.countType=countTypes; (CsD*U`h
} hS)'a^FV
public void setCountId(int countIds){ S4G^z}{_
this.countId=countIds; *QLI3B9V
} b*`lk2oMa/
public String getCountType(){ #7MUJY+
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return countType; KTP8?Q"n0
} cUvz2TK
public int getCountId(){ `-3Ow[
return countId; %d?cP}V
} .7l&1C)i
} a{R%#e\n
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CountCache.java EJsM(iG]~M
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/* s;3= {e.
* CountCache.java QKr,g
* VzY8rI
* Created on 2007年1月1日, 下午5:01 K?BOvDW"`
* ',:*f8Jk
* To change this template, choose Tools | Options and locate the template under `[W[H(AjQ
* the Source Creation and Management node. Right-click the template and choose P*I}yPeb
* Open. You can then make changes to the template in the Source Editor. h"_MA_]~
*/ dHv68*^\'
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package com.tot.count;
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import java.util.*; i(>4wK!!
/** ^-,xE>3o
* y#q?A,C@n
* @author 4<k9?)~(J
*/ /+@p7FqlE
public class CountCache { wS%Q<uK
public static LinkedList list=new LinkedList(); e A#;AQm
/** Creates a new instance of CountCache */ ;4.!H,d
public CountCache() {} 4A_[PM
public static void add(CountBean cb){ ZuS0DPS`L
if(cb!=null){ #6+@M
list.add(cb); nv@8tdrc
} ~c %hWt
} hM{{\yZS
} Uc@Ao:
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CountControl.java B2C$N0R#
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/* i*#-I3
* CountThread.java Yy)tmq
* >D(R YI
* Created on 2007年1月1日, 下午4:57 xHz[t6;4;
* *a #rM"6P
* To change this template, choose Tools | Options and locate the template under z7Q?D^miy
* the Source Creation and Management node. Right-click the template and choose NhaI<J
* Open. You can then make changes to the template in the Source Editor. NiU2@zgl
*/ (Q.waI
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package com.tot.count; ha(Z<
import tot.db.DBUtils; .y@oz7T5
import java.sql.*; YKO){f5
/** ;#oie<
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* L5
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* @author %*`J k#W:
*/ o1FF"tLkN
public class CountControl{ y0'Rmk,
private static long lastExecuteTime=0;//上次更新时间 Il=
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private static long executeSep=60000;//定义更新间隔时间,单位毫秒 7z!tKs"TMT
/** Creates a new instance of CountThread */ 6^%68N1k
public CountControl() {} dIRm q+d^
public synchronized void executeUpdate(){ FRg^c
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Connection conn=null; l}]t~!X=
PreparedStatement ps=null; >rJnayLF
try{ S$Q8>u6Wk
conn = DBUtils.getConnection(); ]>~)<
conn.setAutoCommit(false); M;p
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ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); IHJ=i-
for(int i=0;i<CountCache.list.size();i++){ /J:bWr
CountBean cb=(CountBean)CountCache.list.getFirst(); BV>\ McI+
CountCache.list.removeFirst(); $!8-? ?ML
ps.setInt(1, cb.getCountId()); PDrZY.-
ps.executeUpdate();⑴ ,!7 H]4Qx
//ps.addBatch();⑵ 1e&QSzL
} h $L/<3oP6
//int [] counts = ps.executeBatch();⑶ ;uwRyd
conn.commit(); #m{UrTC
}catch(Exception e){ |aT| l^2R@
e.printStackTrace(); UG'9*(*
} finally{ #ZYVc|sT+
try{ 5ZMR,SZhC
if(ps!=null) { $CY't'6Hn
ps.clearParameters(); -5I2ga
ps.close(); ~:3QBMk::
ps=null; DsT>3
} 34d3g
}catch(SQLException e){} \hM|(*DL
DBUtils.closeConnection(conn); Bc6|n :;u
} =y/8^^
} i1>-QDYnJ
public long getLast(){
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return lastExecuteTime; Lz:(6`S
} Yx eOI#L
public void run(){ ~wJFa'2
long now = System.currentTimeMillis(); IGtl\b=
if ((now - lastExecuteTime) > executeSep) { >|twyb
//System.out.print("lastExecuteTime:"+lastExecuteTime); "QWq_R
//System.out.print(" now:"+now+"\n"); )tl.s)"N
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); +TQ47Zc
lastExecuteTime=now; yp66{o
executeUpdate(); {3.r6ZwCn
} k[HAkB \{
else{ xYhrO
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); brdmz}
} 0 0M@
} `.x
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} n(L\||#+
//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 4Qo]nre!
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类写好了,下面是在JSP中如下调用。 w0C~*fn3l
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<% 72oF ,42y
CountBean cb=new CountBean(); p\JfFfC
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); Um: Hrjw
CountCache.add(cb); dO4{|(z
out.print(CountCache.list.size()+"<br>"); C\di 7 z:
CountControl c=new CountControl(); !kE-_dY6)
c.run(); ;ByOth|9P
out.print(CountCache.list.size()+"<br>"); e(I=^#u6
%>