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: 31cZ6[
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CountBean.java /sr.MT
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/* E]W
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* CountData.java ~d-Q3n?zR
* + cZC$lo
* Created on 2007年1月1日, 下午4:44 kgd
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* B]I*ymc#
* To change this template, choose Tools | Options and locate the template under {t|Q9&
* the Source Creation and Management node. Right-click the template and choose =!u]t&yv
* Open. You can then make changes to the template in the Source Editor. gts09{"}Y
*/ hISYtNWjd"
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package com.tot.count; e!vWGnY
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/** f.0HIc
* z9w]{Zd_,d
* @author A<IV"bo
*/ wLxuSs|
public class CountBean { zEh&@{u?
private String countType; #'.
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int countId; GJ:oUi
/** Creates a new instance of CountData */ -$I$z o
public CountBean() {} #vc!SI
public void setCountType(String countTypes){ udPLWrPF\
this.countType=countTypes; f|Nkk*9$
} DABV}@ K"
public void setCountId(int countIds){ qe/5'dw
this.countId=countIds; :s1.TQ;Y(
} !Wj`U$];
public String getCountType(){ E:;MI{;7
return countType; bl{W{?QI
} 89t"2|9 u
public int getCountId(){ 8( Q[A
return countId; {\X$vaF
} 0^)~p{Zh
} 8mt#S
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CountCache.java -s\R2_(
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/* PP]7_h^2
* CountCache.java ?5F;4oR2g
* {REGoe=W%
* Created on 2007年1月1日, 下午5:01 di7cCn
* g ;XK3R
* To change this template, choose Tools | Options and locate the template under UzW]kY[A<
* the Source Creation and Management node. Right-click the template and choose A)&CI6(
* Open. You can then make changes to the template in the Source Editor. "~KTLf
*/ /m i&7C(6
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package com.tot.count; i~)EUF
import java.util.*; m -0EcA/
/** 7 0EH~
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* @author b1G6'~U -
*/ f{uS
public class CountCache { \f=kQbM
public static LinkedList list=new LinkedList(); f8G<5_!K_
/** Creates a new instance of CountCache */ TX7dwmt)N
public CountCache() {} +|x%a2?x:
public static void add(CountBean cb){ [)il_3t
if(cb!=null){ s#8T46?
list.add(cb); 3{$ >-d
} SR_-wD
} d[nz0LI|mk
} 87m`K Str7
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CountControl.java j`K0D65
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/* }:QoY Nq
* CountThread.java m\E=I5*/
* m=Mk@xfQ#
* Created on 2007年1月1日, 下午4:57 t:xTmK&vt
* %!A-K1Z\D
* To change this template, choose Tools | Options and locate the template under -Owb@Nw
* the Source Creation and Management node. Right-click the template and choose lHHx D
* Open. You can then make changes to the template in the Source Editor. #r1y|)m`
*/ F8M};&=*1r
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package com.tot.count; ln":j?`
import tot.db.DBUtils; E>O@Bv
import java.sql.*; b!teSf
/** kuq&; uk$Q
* ePxAZg$ `>
* @author Q'?VLv|@
*/ mS49l
public class CountControl{ G>jC+0nkry
private static long lastExecuteTime=0;//上次更新时间 {xTh!ih2-
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 DF-.|-^9I
/** Creates a new instance of CountThread */ m Ph=bG
public CountControl() {} ^+gD;a|t
public synchronized void executeUpdate(){ M&sQnPFH
Connection conn=null; I|;C}lfp
PreparedStatement ps=null; %*V r}@BA)
try{ lhf5[Rp
conn = DBUtils.getConnection(); I :bT"N
conn.setAutoCommit(false); @x;(yqOb
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); bfpoX,:
for(int i=0;i<CountCache.list.size();i++){ :"b :uQ
CountBean cb=(CountBean)CountCache.list.getFirst(); A"R(?rQi=
CountCache.list.removeFirst(); P\QbMj1U
ps.setInt(1, cb.getCountId()); =EU;%f
ps.executeUpdate();⑴ d#W^S[[
//ps.addBatch();⑵ .'h^
} &5[+p{2
//int [] counts = ps.executeBatch();⑶ ZCMH?>
conn.commit(); cmq4w&x/
}catch(Exception e){ @xBO[v
e.printStackTrace(); ou`KkY||
} finally{ m'k>U4
try{ $Zkk14
if(ps!=null) { 3\C+g{}e
ps.clearParameters(); {kb7u5-
ps.close(); c\O2|'JzE
ps=null; ,)aUp4*
} .MID)PY-
}catch(SQLException e){} "=JE12=u
DBUtils.closeConnection(conn); sYvlf0
} ,mC=MpfzJ
} YD{N)v
public long getLast(){ e"*ho[
return lastExecuteTime; hb
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} @ `mke4>_
public void run(){ JZE@W-2
long now = System.currentTimeMillis(); =^_a2_BBl
if ((now - lastExecuteTime) > executeSep) { */K]sQZa
//System.out.print("lastExecuteTime:"+lastExecuteTime); v"o@q2f_
//System.out.print(" now:"+now+"\n"); \'iy(8i
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); [;ZC_fD
lastExecuteTime=now; _>?.MUPB
executeUpdate(); iun_z$I<+Z
} GdrVH,j
else{ ^\Q%VTM
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); uY/CiTWr
} #JXXq%4
@
} J8Vzf$t};
} jB0Ts;5
//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 \=xS?(v!
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类写好了,下面是在JSP中如下调用。 ?I"?J/zm
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<% gFfKK`)}D'
CountBean cb=new CountBean(); VwK7\jV
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); IR;3{o
CountCache.add(cb); |
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out.print(CountCache.list.size()+"<br>"); + ef>ek
CountControl c=new CountControl(); }n'W0Sa
c.run(); b^P\Q s*m
out.print(CountCache.list.size()+"<br>"); JeA_mtSQ|
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