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: Qktj
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CountBean.java QKj8~l(
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/* (k{rn3,
* CountData.java ~Y-
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* X\?PnD`,
* Created on 2007年1月1日, 下午4:44 8M{-RlR
* f-w-K)y$ht
* To change this template, choose Tools | Options and locate the template under XkG:1H;Q%
* the Source Creation and Management node. Right-click the template and choose =qQH,{]c6
* Open. You can then make changes to the template in the Source Editor. ?CaMn b8
*/ ,\HZIl[8
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package com.tot.count; PS" ,
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/** &rdz({
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* @author 4G:?U6
*/ MfX1&/Z+
public class CountBean { {8'f>YP
private String countType; ; O6Ez-"
int countId; pZpAb+
/** Creates a new instance of CountData */ ~EYsUC#B_
public CountBean() {} yuTSzl25,/
public void setCountType(String countTypes){ br@GnjG
this.countType=countTypes; ?Ek 3<7d
} 3Kv~lo^
public void setCountId(int countIds){ h KZ<PwBi
this.countId=countIds; Bh'_@PHP
} !=C74$TH
public String getCountType(){ 3#=%2\
return countType; wt8?@lJ"/
} q 9cN2|:
public int getCountId(){ \Vc-W|e
return countId; @
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} xJ2DkZ
} z0@{5e$#Y
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CountCache.java ,Z2fVz~9
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/* GFq,Ca~
* CountCache.java oxs0)B
* _$&C$q$ 1y
* Created on 2007年1月1日, 下午5:01 =)Aav!
* 6c[&[L%
* To change this template, choose Tools | Options and locate the template under ~,*=j~#h
* the Source Creation and Management node. Right-click the template and choose gpIq4Q<
* Open. You can then make changes to the template in the Source Editor. K
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*/ *%[L
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package com.tot.count; -y@#
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import java.util.*; 4pYscB
/** %K9 9_Cl3
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* @author 1
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*/ _TGv"c@V
public class CountCache { Q1cM{$}M
public static LinkedList list=new LinkedList(); !x%$xC^Iz
/** Creates a new instance of CountCache */ B) 5QI
public CountCache() {} 3lkz:]SsE
public static void add(CountBean cb){ xsPY#
if(cb!=null){ kjS9?>i
list.add(cb); 5,i0QT"
} PVNDvUce
} EFd9n
} !CnkG<5z>
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CountControl.java e-4 Qw#cw
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/* LqDj4[}
* CountThread.java !=-{$& {
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* Created on 2007年1月1日, 下午4:57 vtm?x,h
* q6A"+w,N
* To change this template, choose Tools | Options and locate the template under :1O49g3R
* the Source Creation and Management node. Right-click the template and choose h(<2{%j
* Open. You can then make changes to the template in the Source Editor. <WWn1k_
*/ aMLtZ7i>
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package com.tot.count; kMCgfL
import tot.db.DBUtils; vXq2="+
import java.sql.*; w&b?ze{
/** :u
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* @author !4?QR
*/ h;+bHrKji
public class CountControl{ acPX2B[jJ
private static long lastExecuteTime=0;//上次更新时间 v`G [6Z
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 ees^j4
/** Creates a new instance of CountThread */ wjRv=[
public CountControl() {} :iKk"r,2P[
public synchronized void executeUpdate(){ xE0'eC5n^
Connection conn=null; 0@BhRf5
PreparedStatement ps=null; )0tq&
try{ lD K<gd
conn = DBUtils.getConnection(); t XbMP
conn.setAutoCommit(false); rQrh(~\:
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); ,;
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for(int i=0;i<CountCache.list.size();i++){ cBGR%w\t%
CountBean cb=(CountBean)CountCache.list.getFirst(); ^U5g7Emf
CountCache.list.removeFirst(); 6
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ps.setInt(1, cb.getCountId()); `S&.gPE2
ps.executeUpdate();⑴ UA%tI2
//ps.addBatch();⑵ 4:50dj
} n/zTS3<
//int [] counts = ps.executeBatch();⑶ UHaY|I${U
conn.commit(); <,X?+hr
}catch(Exception e){ +~ZFao qf
e.printStackTrace(); oiKY2.yW
} finally{ IXz)xdP
try{ y%wjQC 0~
if(ps!=null) { &_Vd
ps.clearParameters(); r;~2NxMF/
ps.close(); pOmHxFOOK
ps=null; =Zt7}V
} HOY@<'
}catch(SQLException e){} >EJ`Z7E6
DBUtils.closeConnection(conn); "QV?C
} ZD`9Ez)5
} MODi:jsl
public long getLast(){ DO5H(a
return lastExecuteTime; Vs:x3)m5j
}
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public void run(){ yE3l%<;q
long now = System.currentTimeMillis(); HOPi2nf{
if ((now - lastExecuteTime) > executeSep) { @`D`u16]i
//System.out.print("lastExecuteTime:"+lastExecuteTime); 7hq$vI%0
//System.out.print(" now:"+now+"\n"); xDtJ&6uFw
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); 5@3hb ]J
lastExecuteTime=now; ej^pFo
executeUpdate(); '|jN!y^2p
} v;_k*y[VV$
else{ >'MT]@vez
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); )LRso>iOO
} Y`tv"v2
} k O8W>
} \c .^^8r
//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 ;q;}2
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类写好了,下面是在JSP中如下调用。 j56Dt_
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<% exfJm'R?n
CountBean cb=new CountBean(); )r +o51gp
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); q'zV9
CountCache.add(cb); l`M7a9*U
out.print(CountCache.list.size()+"<br>"); G*].g['
CountControl c=new CountControl(); ,|Xibfw
c.run(); ^5- 8'9 w
out.print(CountCache.list.size()+"<br>"); cCWk^lF],
%>