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: D'7SAFOM
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CountBean.java 0F]>Jby
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/* [OM7g'?S0
* CountData.java ,ek_R)&[o
* V`X2>-Ex
* Created on 2007年1月1日, 下午4:44 |*:'TKzNS
* o4j[p3$
* To change this template, choose Tools | Options and locate the template under ?>hPO73{
* the Source Creation and Management node. Right-click the template and choose d^RxQuA
* Open. You can then make changes to the template in the Source Editor. K&bzDzd `
*/ u2[iM d
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package com.tot.count; _I:~@
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/** {/"2Vk<H8
* (}a8"]Z
* @author ^=T$&gD
*/ DSC$i|
public class CountBean { PfreAEv,
private String countType; *i]=f6G
int countId; }'""(,2
/** Creates a new instance of CountData */ "^4_@ oo
public CountBean() {} k,'L}SK
public void setCountType(String countTypes){ A9f)tqbc
this.countType=countTypes; ZNf6;%oGG
} %C$%!C
public void setCountId(int countIds){ H18Tn!RDS
this.countId=countIds; yOphx07 (
} >xF/Pl
public String getCountType(){ L%BNz3:Dt
return countType; N03HQp)g
} L$9.8W
public int getCountId(){ )^m%i]L_
return countId; M:-.o
} {XNREjhm
} CsTF
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CountCache.java :z4)5=
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/* dls
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* CountCache.java /4c\K-Z;
* `&KwtvkdI
* Created on 2007年1月1日, 下午5:01 y=`2\L" O
* n;(\5{a
* To change this template, choose Tools | Options and locate the template under dQ_!)f&w1
* the Source Creation and Management node. Right-click the template and choose MZlk0o2
* Open. You can then make changes to the template in the Source Editor. cc#gEm)3C
*/ Q?3Gk%T0[
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package com.tot.count; ?*E'^~,H)
import java.util.*; *$p2*%7Ne
/** E0u~i59Z
* >;L6xt3
* @author _{r=.W+w
*/ %K\?E98M
public class CountCache { 6xWe=QGE
public static LinkedList list=new LinkedList(); +)j$|x~(A
/** Creates a new instance of CountCache */ zRq-b`<7V
public CountCache() {} _acE:H
public static void add(CountBean cb){ --HF8_8;'
if(cb!=null){ T(e!_VY|m
list.add(cb); lmfi
} m\$\ 09
} .Jt[(;
} T-5nB>)
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CountControl.java 5$wpL(:R(
wm)#[x #
/* 3E>frR\!I
* CountThread.java Z$0uH* h
* mH Ic f{RG
* Created on 2007年1月1日, 下午4:57 )=AHf?hn
* H2um|6>
* To change this template, choose Tools | Options and locate the template under O)ME"@r@:
* the Source Creation and Management node. Right-click the template and choose JcbwDlUb
* Open. You can then make changes to the template in the Source Editor. XVKfl3'%
*/ Q(<)KZIK
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package com.tot.count; o(:[r@Z0z
import tot.db.DBUtils; GlbySD@
import java.sql.*; "\}@gV#r$A
/** FI3)i>CnW
* >TQH|}|6(y
* @author xKQ+{"?-^g
*/ PI`jExL
public class CountControl{ Aj2OkD
private static long lastExecuteTime=0;//上次更新时间 d!:6[7X6
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 iMs5zf<M
/** Creates a new instance of CountThread */ =Qgt${|
public CountControl() {} 9(6I<]#
public synchronized void executeUpdate(){ |1b_3?e
Connection conn=null; VUhbD
PreparedStatement ps=null; L
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try{ mml<9fbH
conn = DBUtils.getConnection(); 91$]Qg,lB
conn.setAutoCommit(false); 2Z3('?\z~
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); *e-A6Sh
for(int i=0;i<CountCache.list.size();i++){ *cC_j*1@
CountBean cb=(CountBean)CountCache.list.getFirst(); Eh|]i;G%
CountCache.list.removeFirst(); e46/{4F,
ps.setInt(1, cb.getCountId()); #Sa27$&.>
ps.executeUpdate();⑴ !zPa_`P
//ps.addBatch();⑵ .!G94b
} )l!3(
//int [] counts = ps.executeBatch();⑶ (HSgEs1d
conn.commit();
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}catch(Exception e){ %-<'QYYP
e.printStackTrace();
"dI;
} finally{ nv0]05.4
try{ Er{#ziN+
if(ps!=null) { w^LuIbA
ps.clearParameters(); 7}vg.hmZ
ps.close(); [+OnV&
ps=null; 2AtLyN'.
}
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}catch(SQLException e){} bks/`rIA
DBUtils.closeConnection(conn); M?[h0{^K
} TEMw8@b
} .N*Pl(<[
public long getLast(){ MW PvR|Q
return lastExecuteTime; dlG=Vq&Y
} 2^)1N>"g
public void run(){ _>v<(7
long now = System.currentTimeMillis(); 8
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if ((now - lastExecuteTime) > executeSep) { cKn`/\.H
//System.out.print("lastExecuteTime:"+lastExecuteTime); fm^@i;D
//System.out.print(" now:"+now+"\n"); 7{xh8#m
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); cZ<A0
lastExecuteTime=now; /__PSK
executeUpdate(); h68]=KyK
} BSkDpr1C
else{ Y;)dct
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); {U84 _Pi
} P|HKn,ar
} F* .g;So
} tqy@iEz+
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 [xT:]Pw}
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类写好了,下面是在JSP中如下调用。 0d3+0EN{
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<% .cR
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CountBean cb=new CountBean(); efD)S92
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); \tRG1&{$%
CountCache.add(cb); }=v)Js
out.print(CountCache.list.size()+"<br>"); NNF>Xa`9,
CountControl c=new CountControl(); JICawj:I
c.run(); Z(ZiFPx2Z
out.print(CountCache.list.size()+"<br>"); vBsP+K
%>