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: BrZ17
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CountBean.java 2(Yt`3Go(
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/* g|4>S<uC
* CountData.java ^?0?*
* %(s2{$3
* Created on 2007年1月1日, 下午4:44 ma"M? aM
* A v;NQt8ut
* To change this template, choose Tools | Options and locate the template under 1 7iw`@
* the Source Creation and Management node. Right-click the template and choose Y'R/|:YL@
* Open. You can then make changes to the template in the Source Editor. +j$nbU0U
*/ k9VWyq__
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package com.tot.count; 6k+tO%{~
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/** blaXAqe
* .Pux F
* @author W4h ]4X
*/ Z hCjY
public class CountBean { )_?H BTG
private String countType; UCo<ie\V
int countId; f&&Ao
/** Creates a new instance of CountData */ C?6q]k]r
public CountBean() {} -:b<~S[
public void setCountType(String countTypes){ 2t=&h|6EW
this.countType=countTypes; 2{g&9
} {WeRFiQ?-
public void setCountId(int countIds){ jX t5.9 t
this.countId=countIds; \oP
} ?b(DDQMf
public String getCountType(){ M,Lq4 bz
return countType; f.R;<V.)
} R m2M
public int getCountId(){ n~i^+pD@
return countId; ;B:\e8
} .l,NmF9
} *_ajb:
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CountCache.java 'w|N}
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/* s(MdjWw
* CountCache.java 90H/Txq
* ;BHIss7
* Created on 2007年1月1日, 下午5:01 \z.p [;'ir
* |I.5]r-EK
* To change this template, choose Tools | Options and locate the template under GB6(WAmr
* the Source Creation and Management node. Right-click the template and choose -,$:^4
* Open. You can then make changes to the template in the Source Editor. oiz]Bd
*/ z34+1d
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package com.tot.count; \,I{*!hw
import java.util.*; a3He-76
/** ZCfd<NS?
* %r:4'$E7|
* @author KkR.p,/
*/ Lk-h AN{[
public class CountCache { }F3}"Ik'L
public static LinkedList list=new LinkedList(); +]Z*_?j9{
/** Creates a new instance of CountCache */ t
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public CountCache() {} ~6OdwGWV
public static void add(CountBean cb){ 8PG&/"K
if(cb!=null){ FGpV
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list.add(cb); J]Q-#g'Z
} h?GE-F
} 2k`Q+[?{q>
} j?!/#'
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CountControl.java gLbTZM4i
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/* ?.nD!S@
* CountThread.java _Vr}ipx-k
* ,awkL
:
* Created on 2007年1月1日, 下午4:57 L 1q]
* eHyIFoaC/
* To change this template, choose Tools | Options and locate the template under "YVvmCp
* the Source Creation and Management node. Right-click the template and choose Hqu?="f=
* Open. You can then make changes to the template in the Source Editor. 7TZ,bD_
*/ Uz`OAb
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package com.tot.count; ORfMp'uP=
import tot.db.DBUtils; `3dGn.M
import java.sql.*; n." XiXsN
/** k{^iv:
* O*Z-3l
* @author *uF Iw}C/
*/ 01+TVWKX
public class CountControl{ C3C&hq\%
private static long lastExecuteTime=0;//上次更新时间 `O?j -zR
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 W{kTM4
/** Creates a new instance of CountThread */ [Lf8*U"
public CountControl() {} 4&B|rf
public synchronized void executeUpdate(){ y*I,i*iv
Connection conn=null; : p7PiqQ
PreparedStatement ps=null; mxCqN1:#
try{ ' KNg;
conn = DBUtils.getConnection(); 4}<[4]f?|
conn.setAutoCommit(false); p.vxrk`c
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); _^F%$K6
for(int i=0;i<CountCache.list.size();i++){ Z&GjG6t
CountBean cb=(CountBean)CountCache.list.getFirst(); F=;nWQ&
CountCache.list.removeFirst(); Z%VgAV>>
ps.setInt(1, cb.getCountId()); 7t6TB*H
ps.executeUpdate();⑴ d s}E|Q
//ps.addBatch();⑵ kM(,8j
} 2K{)8;^
//int [] counts = ps.executeBatch();⑶ Qmj%otSg
conn.commit(); ?a~#`<
}catch(Exception e){ MAgoxq~;V
e.printStackTrace(); RM!VAFH
} finally{ sfCU"O2G
try{ ER<Z!*2
if(ps!=null) { #2qv"ntW
ps.clearParameters(); 8fQXif\z
ps.close(); =o4McV}
ps=null; hDTM\>.c;s
} i0[mU,
}catch(SQLException e){} ezr'"1Ba}
DBUtils.closeConnection(conn); (w/lZt
} >uYGY{+j[
} }A7]bd
public long getLast(){ Gq.fQ_oOb
return lastExecuteTime; C33=<r[;N<
} kBrU%[0O
public void run(){ bm(.(0MI
long now = System.currentTimeMillis(); ?L>}(
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if ((now - lastExecuteTime) > executeSep) { bHmn0fZ9
//System.out.print("lastExecuteTime:"+lastExecuteTime); `q?@ Ob&
//System.out.print(" now:"+now+"\n"); lJU]sZ9~b
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); cb _nlG!
lastExecuteTime=now; IjRUL/\=
executeUpdate(); VOrBNu
} ?qczMck_
else{ |Q#CQz
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); 6b h.5|
} e|.a%,Dcy
} * l-F
} /SJI ~f+$
//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+
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类写好了,下面是在JSP中如下调用。 :ZU-Vi.b
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<% -KiI&Q
CountBean cb=new CountBean(); O[HBw~
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); 7u[$
CountCache.add(cb); lBOxB/`
out.print(CountCache.list.size()+"<br>"); ?xzDz
CountControl c=new CountControl(); NE-c[|rq
c.run(); 42,K8
out.print(CountCache.list.size()+"<br>"); cu"ge]},
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