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: 8 c5=Px2\
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CountBean.java <|1Kh ygv
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/* 04#<qd&ob@
* CountData.java 3T~DeqAyw
* x<1t/o
* Created on 2007年1月1日, 下午4:44 ~ugH2jiB
* ?yKG\tPhM
* To change this template, choose Tools | Options and locate the template under $%.,=~W7
* the Source Creation and Management node. Right-click the template and choose u-@;Q<v$
* Open. You can then make changes to the template in the Source Editor. u]sxX")
*/ _@! yj
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package com.tot.count; J6gn!
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/** E'^ny4gL
* iM M s3
* @author FYIz_GTk
*/ hq?F81
public class CountBean { bJ^Jmb
private String countType; T$1(6<:+.
int countId; Zx^R -9
/** Creates a new instance of CountData */ )WsR
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public CountBean() {} gUH|?@f
public void setCountType(String countTypes){ X/FR e[R
this.countType=countTypes; bK k7w#y
} z?W kHQ9
public void setCountId(int countIds){ *Rgl(Ba
this.countId=countIds; =Y*zF>#lP
} #6mr'e1
public String getCountType(){ ~(]'ah,
return countType; EOXuc9>G
} y(X^wC
public int getCountId(){ MUUhg
return countId; oF_
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} _7<G6q2(
} C:z7R" yj
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CountCache.java 3j2d&*0
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/* :PNhX2F
* CountCache.java (dP9`Na]
* ro8C^d]
* Created on 2007年1月1日, 下午5:01 !eP0b~$/^J
* wlpcuz@
* To change this template, choose Tools | Options and locate the template under Rp
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* the Source Creation and Management node. Right-click the template and choose I5E+=.T*ar
* Open. You can then make changes to the template in the Source Editor. M$e$%kPShE
*/ 2 ]}e4@{
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package com.tot.count; 2{S*$K[M
import java.util.*; rEoOv
/** g{JH5IZ~
* ^_/gM[H.
* @author rB_ESNx
*/ e?WI=Og
public class CountCache { H>wXQ5 ?W;
public static LinkedList list=new LinkedList(); o3HS|
/** Creates a new instance of CountCache */ =z'533C
public CountCache() {} EUS^Gtc
public static void add(CountBean cb){ $E^*^({
if(cb!=null){ A:*$r Hbzl
list.add(cb); M1I4Ot
} d.k'\1o
} Pt7C/
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} n6{nx[%7N7
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CountControl.java Ox6^=D"
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/* yppXecFJ
* CountThread.java 9mEhZ"
* Rk}=SB-
* Created on 2007年1月1日, 下午4:57 e r"gPW
* q,]57s
* To change this template, choose Tools | Options and locate the template under sNJ?Z"5k1h
* the Source Creation and Management node. Right-click the template and choose `!.c_%m2
* Open. You can then make changes to the template in the Source Editor. !%QbE[Kl>
*/ f0g&=k{OD
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package com.tot.count; w^/"j_p@
import tot.db.DBUtils; )T@+"Pw8t
import java.sql.*; BA_l*h%=Cc
/** z_a7HCG2
* h|ja67VG
* @author N~B'gJJDx
*/ %j ?7O00@
public class CountControl{ +N!/>w]n
private static long lastExecuteTime=0;//上次更新时间 r`C t/]c
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 7/BA!V(na
/** Creates a new instance of CountThread */ L'a>D
public CountControl() {} #b{;)C fL
public synchronized void executeUpdate(){ s$VLVT*6
Connection conn=null; EZ^M?awB4
PreparedStatement ps=null; e3kdIOu5
try{ x2+M0 }g
conn = DBUtils.getConnection(); 'Y5=A!*@tf
conn.setAutoCommit(false); RueL~$*6.~
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); UbSD?Ew@35
for(int i=0;i<CountCache.list.size();i++){ p fg>H
CountBean cb=(CountBean)CountCache.list.getFirst(); zuvP\Y=V`
CountCache.list.removeFirst(); 66cPoG
ps.setInt(1, cb.getCountId()); I)4NCjcCw
ps.executeUpdate();⑴ :N>s#{+"3
//ps.addBatch();⑵ Fr9_!f
} KT8]/T`U
//int [] counts = ps.executeBatch();⑶ SMh[7lU`
conn.commit(); sB`zk[R;
}catch(Exception e){ i%9xt1c_
e.printStackTrace(); 5VW*h
} finally{ }ABHGr5[
try{ q.PXO3T
if(ps!=null) { l
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ps.clearParameters(); %:[Y/K-
ps.close(); )"<:Md$7
ps=null; vm "dE4W=
} Z6oA>D
}catch(SQLException e){} 1FmVx
DBUtils.closeConnection(conn); G-sA)WOF
} yy|F6Pq3`
} %R1$M318
public long getLast(){ <2 S?QgR,
return lastExecuteTime; l%$co07cX
} k%lz%r
public void run(){ G7H'OB
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long now = System.currentTimeMillis(); *7 >K" j
if ((now - lastExecuteTime) > executeSep) { $9O%,U@
//System.out.print("lastExecuteTime:"+lastExecuteTime); XRR`GBI
//System.out.print(" now:"+now+"\n"); i fbO<
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); HCKj8-*
lastExecuteTime=now; qct:xviH<|
executeUpdate(); ]Q0+1'yuK
} Zw"K69A)
else{ :0B'
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//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); Ie8jBf -
} m;KD@E!
} 4PAuEM/z
} Nb@zn0A(;
//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 B>W!RyH8o
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类写好了,下面是在JSP中如下调用。 _m|Tr*i8
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<% RP4P"m(
CountBean cb=new CountBean(); ,BG
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cb.setCountId(Integer.parseInt(request.getParameter("cid"))); 'w5g s}1D
CountCache.add(cb); ,,[pc
out.print(CountCache.list.size()+"<br>"); +=A53V[C
CountControl c=new CountControl(); 7cJh^M
c.run(); x>=8~wIK
out.print(CountCache.list.size()+"<br>"); F[5\
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%>