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:
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CountBean.java Hm`9M.5b
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/* /`D]m?
* CountData.java u
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* w@nN3U+
* Created on 2007年1月1日, 下午4:44 it5].A&
* r3hjGcpaX
* To change this template, choose Tools | Options and locate the template under c_O|?1
* the Source Creation and Management node. Right-click the template and choose <y6M@(b
* Open. You can then make changes to the template in the Source Editor. #; E,>0
*/ o9#
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package com.tot.count; ~!,'z
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/** G#)>D$Ck#
* q*@7A6:FV>
* @author 5IBe;o
*/ xRP#}i:m
public class CountBean { /t%IU
private String countType; ??aOr*%
int countId; <QugV3e
/** Creates a new instance of CountData */ W&}R7a@:<~
public CountBean() {} MT$OjH'Q`
public void setCountType(String countTypes){ ^]Lr_k
this.countType=countTypes; 7}%3Aw6]S
} a>.2Q<1
public void setCountId(int countIds){ -}MWA>an8
this.countId=countIds; w%VHq z$
} 4B<D.i ;}
public String getCountType(){ @&S4j]rq
return countType; r=s,Ath
} oA"t`,3
public int getCountId(){ 4NQS'*%D
return countId; E4HG`_cWb
} u\ytiGO*
} t=~al8
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CountCache.java 6t*pV
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/* E%3WJ%A
* CountCache.java 6BFtY+.y
* 8K]fw{-$L
* Created on 2007年1月1日, 下午5:01 .O3i"X]
* pYI`5B4
* To change this template, choose Tools | Options and locate the template under Od>Ta_
* the Source Creation and Management node. Right-click the template and choose (pH13qU5
* Open. You can then make changes to the template in the Source Editor. >72j,0=e
*/ `w@fxv
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package com.tot.count; PX(.bP2^Lq
import java.util.*; }v;@1[.B
/** c*1t<OAS~
* %QVX1\>]
* @author -G(z!ed
*/ O:+#k-?
public class CountCache { <3LyNG.
public static LinkedList list=new LinkedList(); KU"?ZI
/** Creates a new instance of CountCache */ vZTX3c:,1
public CountCache() {} s)_7*DY
public static void add(CountBean cb){ f/&Dy'OV7
if(cb!=null){ uwyzxj
list.add(cb); gZM\RJZ_
} SM@l4GH
} x5WFPY$wM
} -F/"W
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CountControl.java ?M;2H{KG:
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/* gPT-zul
* CountThread.java 245(ajxHC
* TCX*$ac"
* Created on 2007年1月1日, 下午4:57 &0It"17Ej
* 69!J'kM[
* To change this template, choose Tools | Options and locate the template under eq<xO28z
* the Source Creation and Management node. Right-click the template and choose "k)( ,
* Open. You can then make changes to the template in the Source Editor. zM|d9TS
*/ tU}CRh
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package com.tot.count; 0X~
import tot.db.DBUtils; T3@wNAAU
import java.sql.*; $`i$/FE
/** YS{])+s
* fk5!/>X
* @author fS>W-
*/ 6$4G&'J
public class CountControl{ ^IjKT
private static long lastExecuteTime=0;//上次更新时间 Lf3Ri/@ p
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 >O&(G0!N+}
/** Creates a new instance of CountThread */ *
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public CountControl() {} mK%!9F
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public synchronized void executeUpdate(){ V);{o>%.K
Connection conn=null; [0lCb"
PreparedStatement ps=null; Z WL/ AC
try{ -=&r}/&
conn = DBUtils.getConnection(); js^@tgf$x&
conn.setAutoCommit(false); G':mc{{
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); f h)Cz)
for(int i=0;i<CountCache.list.size();i++){ Qi&!IG
CountBean cb=(CountBean)CountCache.list.getFirst(); _ ;O$ot\5
CountCache.list.removeFirst(); )r~$N0\D
ps.setInt(1, cb.getCountId()); %DqF_4U 9
ps.executeUpdate();⑴ A@Z&ZBDg
//ps.addBatch();⑵ ? #-"YO7
} 3=o3VGZP
//int [] counts = ps.executeBatch();⑶ U)=StpTT
conn.commit(); B0?E$8a
}catch(Exception e){ |+~CdA
e.printStackTrace(); _'ltz!~
} finally{ pZ/x,b#.
try{ 8v8?D8\=|
if(ps!=null) { 5,:>.LRA
ps.clearParameters(); .</d$FM JE
ps.close(); R61.!ql%w
ps=null; ctTg-J2.
} u_dTJ,m
}catch(SQLException e){} ZK[4 n5}
DBUtils.closeConnection(conn); izebQVQO*
} ` Xhj7%>
} -N<s =
public long getLast(){ N$aLCX
return lastExecuteTime; T6=c9f?7
} .>zXz%p
public void run(){ cWl
long now = System.currentTimeMillis(); B# |w}hj
if ((now - lastExecuteTime) > executeSep) { LcoJltY{5
//System.out.print("lastExecuteTime:"+lastExecuteTime); Om0Z\GP=
//System.out.print(" now:"+now+"\n"); @.yp IE\
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); ?SK1*; i
lastExecuteTime=now; !>TVDN>
executeUpdate(); 4`o_r%
} "o*(i7T=n
else{ *NS:X7p!V
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); q{ItTvL
} S;kI\;
} O]DZb+O"
} Zgkk%3'^'
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 "EQ`Q=8
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类写好了,下面是在JSP中如下调用。 v(W$\XH
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<% hk3}}jc
CountBean cb=new CountBean(); iBVV5 f
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); T6=, A }t-
CountCache.add(cb);
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out.print(CountCache.list.size()+"<br>"); OIGu`%~js
CountControl c=new CountControl(); -GLI$_lLF
c.run(); ts`c_hH,1'
out.print(CountCache.list.size()+"<br>"); {f((x1{HZx
%>