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: KG=h&
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CountBean.java .B\ 5OI,]
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/* LGl2$#x
* CountData.java (<)]sp2
* AhNq/?Q Q~
* Created on 2007年1月1日, 下午4:44 LA`*_|}qcR
* ak;*W
* To change this template, choose Tools | Options and locate the template under A]DTUdL
* the Source Creation and Management node. Right-click the template and choose 4)("v-p
* Open. You can then make changes to the template in the Source Editor. !=N"vD*
*/ *guoWPA|Ij
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package com.tot.count; ZfB"
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/** PP!SK2u"L
* t1%_DPD%W
* @author !U5Wr+83
*/ ,%)6jYHR w
public class CountBean { [h,Q Bz
private String countType; )LyojwY_g
int countId; DS)RX.k_#
/** Creates a new instance of CountData */ a|?4)
public CountBean() {} VhNz8)
public void setCountType(String countTypes){ Iyyh!MVF
this.countType=countTypes; EbdfV-E
} lgb?)=
public void setCountId(int countIds){ 3%E74 mOcD
this.countId=countIds; y>aZXa
} .<Zy|1
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public String getCountType(){ c.j$9=XLBG
return countType; ,L`$09\
} p8]68!=W\F
public int getCountId(){ |Z*J/v'@p
return countId; }5(Ho$S(
} ka3u&3"
} vo#UtN:q
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CountCache.java ph-ATJ"
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/* %Jrt4sg[j-
* CountCache.java 67VT\f
* di>cMS 4 c
* Created on 2007年1月1日, 下午5:01 qk;{cfzHA
* xa
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* To change this template, choose Tools | Options and locate the template under )lZp9O
* the Source Creation and Management node. Right-click the template and choose dx+hhg \L
* Open. You can then make changes to the template in the Source Editor. $]/Zxd
*/ sUU{fNC6|
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package com.tot.count; 1SR+m>pL
import java.util.*; r}jGUe}d
/** k0Uyf~p~
* >b]S3[Q(
* @author t>[KVVg
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*/ 6#Q K%[1!>
public class CountCache { Qu]z)";7
public static LinkedList list=new LinkedList(); 7K5P8N
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/** Creates a new instance of CountCache */ mD/MJt5
public CountCache() {} 7Ddaf>
public static void add(CountBean cb){ F
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if(cb!=null){ N+y&,N,
list.add(cb); th&[Nt7
} P[k$vD
} QJ7L7S
} l!g]a2x*
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CountControl.java kVy\b E0o
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/* *7wAkljP
* CountThread.java w18y}mS"H
* .k0~Vh2u
* Created on 2007年1月1日, 下午4:57 14"J d\M8
* 6A=8+R'`F
* To change this template, choose Tools | Options and locate the template under |H!9fZO
* the Source Creation and Management node. Right-click the template and choose mI>,.&eo
* Open. You can then make changes to the template in the Source Editor. 2[r^M'J
*/ [Ts"OPb%~
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package com.tot.count; <&:=z?30"
import tot.db.DBUtils; h`H,a7
import java.sql.*; +fnK/%b
/** PxfY&;4n!
* z$kenhFG/
* @author {4-[r#R<M
*/ Yp:KI7
public class CountControl{ q.()z(M7
private static long lastExecuteTime=0;//上次更新时间 v= N!SaK{
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 w&x!,yd;
/** Creates a new instance of CountThread */ QurW/a
public CountControl() {} ZPD[5)~
public synchronized void executeUpdate(){ Nq@+'<@p$
Connection conn=null; ~O1&@xX
PreparedStatement ps=null; &|`C)6[C
try{ kGN+rHo
conn = DBUtils.getConnection(); '_$uW&{NI
conn.setAutoCommit(false); h)Ff2tX
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); !0dNQ[$82
for(int i=0;i<CountCache.list.size();i++){ w/IZDMBf|
CountBean cb=(CountBean)CountCache.list.getFirst(); Vo"RO$%ow*
CountCache.list.removeFirst(); +|ycvHd
ps.setInt(1, cb.getCountId()); _BDK`D
ps.executeUpdate();⑴ MXyaE~LK
//ps.addBatch();⑵ hsw9(D>jp
} e A}%C.ZR
//int [] counts = ps.executeBatch();⑶ 2^^=iU=!<|
conn.commit(); d`/tE?Gw
}catch(Exception e){ G7CG~:3h+
e.printStackTrace(); ]$,UPR/3
} finally{ UAyC.$!
try{ -@Uqz781
if(ps!=null) { q/4 [3h
ps.clearParameters(); nO)X!dp}J
ps.close(); =k oSUVO0
ps=null; A<B=f<N3gV
} A|@_}h"WG
}catch(SQLException e){} d` [HT``
DBUtils.closeConnection(conn); gy;+_'.j
} :Pv*,qHE
} /AQMFx4-5
public long getLast(){ "$}vP<SM
return lastExecuteTime; "XT"|KF|D
} 1\r|g2Z
:
public void run(){ 9Fr3pRIJ
long now = System.currentTimeMillis(); po}F6m8bX
if ((now - lastExecuteTime) > executeSep) { 6AWKLFMV
//System.out.print("lastExecuteTime:"+lastExecuteTime); {N#KkYH{"
//System.out.print(" now:"+now+"\n"); DSj(]U~r
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); UYz0PSV=.
lastExecuteTime=now; 8dlw-Q'S
executeUpdate(); @e'5E^
} RAp=s
else{ /P
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//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); Q3y;$ "
} 3S&U!
} }>[G5[\
} TET`b7G
//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 _Um d
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类写好了,下面是在JSP中如下调用。 _kY#D;`:r
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<% h?$T!D>
CountBean cb=new CountBean(); 3<=G?of
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); /By)"
CountCache.add(cb); M1%Dg'}G
out.print(CountCache.list.size()+"<br>"); _A0mxq
CountControl c=new CountControl(); J=dJsk
c.run(); UG<79"\i
out.print(CountCache.list.size()+"<br>"); ]@M5&
%>