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: he3SR@\T
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CountBean.java eBN)g^
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/* bucR">_p
* CountData.java 7Ob*Yv=[
* u8zbYd3
* Created on 2007年1月1日, 下午4:44 }}{!u0N},V
* 6"j_iB
* To change this template, choose Tools | Options and locate the template under {.e=qQ%P5)
* the Source Creation and Management node. Right-click the template and choose :q##fG'm/
* Open. You can then make changes to the template in the Source Editor. iP~,n8W
*/ *y[PNqyd
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package com.tot.count; ~89P[$6
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/** :HViX:]H
* +~Cy$MCX
* @author Fr?z"
*/ e59dVFug.U
public class CountBean { P3tx|:gV
private String countType; G1T^a>tj4
int countId; Q'apG)0I
/** Creates a new instance of CountData */ !v#xb3"/
public CountBean() {} fg%&N2/(.B
public void setCountType(String countTypes){ _,h@:Xij
this.countType=countTypes; VU|dV\>
} j|.} I
public void setCountId(int countIds){ V)o,1
this.countId=countIds; \J^
} 2+8#H.
public String getCountType(){ y9Y1PH7G
return countType; tY W>t9
} d~tuk4F
public int getCountId(){ l":c
return countId; )bO BQbj
} 5R MS(
} $e%2t^ i.g
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CountCache.java $.6K!x{(
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/*
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* CountCache.java >gtQw!
* >v;8~pgO
* Created on 2007年1月1日, 下午5:01 :y]Omp
* \@a$'
* To change this template, choose Tools | Options and locate the template under H!e 3~+)
* the Source Creation and Management node. Right-click the template and choose >P KBo
* Open. You can then make changes to the template in the Source Editor. Weoj|0|t
*/ VUU]Pu &
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package com.tot.count; *2"6fX[
import java.util.*; rk2xKm^w
/** $ls[|N:y0l
* C@y8.#l
* @author AS!6XT
*/ 5,"l0nrk
public class CountCache { 3{Nbp
public static LinkedList list=new LinkedList(); %rQuBi# 1f
/** Creates a new instance of CountCache */ `\>.h
public CountCache() {} +y+"Fyl
public static void add(CountBean cb){ xk~IN%\
if(cb!=null){ &tR(n$M@>
list.add(cb); jPvDFT^d/
} 0:Xxl76v4
} @=S}=cl
} ^y viV
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CountControl.java ]T!
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/* a[bBT@f
* CountThread.java U09.Y
* q=HHNjj8
* Created on 2007年1月1日, 下午4:57 +H/jK @
* 7"X>?@
* To change this template, choose Tools | Options and locate the template under 4S0>-?{
* the Source Creation and Management node. Right-click the template and choose F7m?xy
* Open. You can then make changes to the template in the Source Editor. ge3sU5iZ
*/ >r/rc`Q
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package com.tot.count; Rn%N&1
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import tot.db.DBUtils; Ko>&)%))$X
import java.sql.*; f67NWFX
/** 4o:hyh
* R$kpiqK
* @author =tTqN+4
*/ 2],_^XBvB
public class CountControl{ p4> $z& _
private static long lastExecuteTime=0;//上次更新时间 #h!*dj"
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 \/7i-B]G7
/** Creates a new instance of CountThread */ Z[!d*O%R_
public CountControl() {} Ey{%XR+*;
public synchronized void executeUpdate(){ 1iT\df
Connection conn=null; 23(=Xp3;>
PreparedStatement ps=null; 73A)lU.
try{ 31+;]W=
conn = DBUtils.getConnection(); {Ee>n^1
conn.setAutoCommit(false); B-.v0R`5
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); X#a`K]!B
for(int i=0;i<CountCache.list.size();i++){ .V9e=yW!*
CountBean cb=(CountBean)CountCache.list.getFirst(); zboF
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CountCache.list.removeFirst(); fJ*:{48
ps.setInt(1, cb.getCountId()); <|O^>s;
ps.executeUpdate();⑴ PALl sGlf
//ps.addBatch();⑵ C.:=lo B
} Vpfp}pL
//int [] counts = ps.executeBatch();⑶ `7aDEzmJ
conn.commit(); y]..=z_ql
}catch(Exception e){ t HD
e.printStackTrace(); `;,Pb&W~
} finally{ 6< J
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try{ YO{GU7
if(ps!=null) { m^%|ZTrwN7
ps.clearParameters(); 9_ICNG%
ps.close(); M/PFPJ >`
ps=null; $DFv30 f
} p5=|Y^g !
}catch(SQLException e){} +YOKA*
DBUtils.closeConnection(conn); qJ!Z~-hS
} 7z6b@$,
} \ A1uhHP!
public long getLast(){ k@>\LR/v
return lastExecuteTime; yDb'7(3-
} >e5 *prx+
public void run(){ P=L$;xgp
long now = System.currentTimeMillis(); |6:=}dE#[
if ((now - lastExecuteTime) > executeSep) { _,Fny_u=;
//System.out.print("lastExecuteTime:"+lastExecuteTime); _fFU#k:MU
//System.out.print(" now:"+now+"\n"); 7x]4`#u
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); A\rt6/
lastExecuteTime=now; <HWS:'1
executeUpdate(); @4~=CV%j
} mAgF73,3
else{ J`M&{UP
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); ,iNv'
} JN/UUfj
} 4Ph0:^i_
} vP%tk s+.
//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 ~jU/<~s
Hi!Jj
类写好了,下面是在JSP中如下调用。 80}+MWdo
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<% |as!Ui/J/
CountBean cb=new CountBean(); S&O3HC
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); foF19_2 ,
CountCache.add(cb); 4!62/df
out.print(CountCache.list.size()+"<br>"); Gz
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CountControl c=new CountControl(); vq*Q.0 M+
c.run(); VO3pm6r5
out.print(CountCache.list.size()+"<br>"); 5F+APz7
%>