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: jF0>wm
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CountBean.java \MB$ Cwc
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/* 6l&,!fd
* CountData.java (A\\s$fE/1
* ?=V;5H.
* Created on 2007年1月1日, 下午4:44 Z6IWQo,)Rh
* DN;3VT.-
* To change this template, choose Tools | Options and locate the template under z?'z{+HY
* the Source Creation and Management node. Right-click the template and choose V&J'2Lq
* Open. You can then make changes to the template in the Source Editor. i^"!"&tW#
*/ Nh"U~zlh
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package com.tot.count; m,PiuR>
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/** Mk!bmFZOZ
* &ZI-#(P
* @author zAH6SaI$
*/ |?4NlB6
public class CountBean { "WzD+<oL
private String countType; -nDY3$U/
int countId; z^\-x9vL
/** Creates a new instance of CountData */ @k-iy-|3)
public CountBean() {}
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public void setCountType(String countTypes){ "43F.!P
this.countType=countTypes; CRPE:7,D
} 9i+`,r
public void setCountId(int countIds){ >IJX=24Rc
this.countId=countIds; F $1f8U8
} kxt/I<cs
public String getCountType(){ c]R27r E
return countType; xt1\Sie
} ^JAp#?N^9
public int getCountId(){ 8QQh1q2
return countId; 3_ko=& B$
} (ty&$
} DIx.a^LR
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CountCache.java 59BB-R,V
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/* t
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* CountCache.java a6\`r^ @
* j?1wP6/NP
* Created on 2007年1月1日, 下午5:01 #M@~8dAH}M
* 5Kw?#
* To change this template, choose Tools | Options and locate the template under ~{-9qOGw;
* the Source Creation and Management node. Right-click the template and choose U;t1 K
* Open. You can then make changes to the template in the Source Editor. %BF,;(P
*/ nB6 $*'
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package com.tot.count; Lwn
import java.util.*; "D'"uMS`H
/** 61](a;Di
* 8yk4#CZ
* @author L5r02VzbD
*/ >35W{d
public class CountCache { H`1q8}m
public static LinkedList list=new LinkedList(); @;}vK=6L
/** Creates a new instance of CountCache */ H
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public CountCache() {} __}ut+H^5p
public static void add(CountBean cb){ ZP'0=
if(cb!=null){ HJJ;gTj
list.add(cb); Sm;@MI<@/
} 8^sh@j2L
} 17-B'Gl!<%
} c&C*'c-r
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CountControl.java ox5WboL
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/* Q hdG(`PY~
* CountThread.java izs=5
* ojc.ykP$
* Created on 2007年1月1日, 下午4:57 Uo;a$sR
* DMlr%)@{
* To change this template, choose Tools | Options and locate the template under h.q9p!
* the Source Creation and Management node. Right-click the template and choose Ko0?c.l
* Open. You can then make changes to the template in the Source Editor. p}8?#5`/w
*/ d'iSvd.
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package com.tot.count; Z"$iB-]
import tot.db.DBUtils; T"1=/r$Ft
import java.sql.*; X.ecA`0
/** pfHfw,[
* n;wViw
* @author %<fs \J^k
*/ >R5A@0@d5
public class CountControl{ l+j
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private static long lastExecuteTime=0;//上次更新时间 ,0{x-S0jX<
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 <<R2
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/** Creates a new instance of CountThread */ w |abaMam
public CountControl() {} {vdY(
public synchronized void executeUpdate(){ \&47u1B
Connection conn=null; aJ}hlM>
PreparedStatement ps=null; oU se~
try{ Q]e]\J
conn = DBUtils.getConnection(); @km4qJZ
conn.setAutoCommit(false); 2_}oOt?qiM
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); LXaq
for(int i=0;i<CountCache.list.size();i++){ @saK:z
CountBean cb=(CountBean)CountCache.list.getFirst(); @WNqD*)1
CountCache.list.removeFirst();
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ps.setInt(1, cb.getCountId()); 5p6/dlN-a
ps.executeUpdate();⑴ f3S 8~!
//ps.addBatch();⑵ '2
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} 7M8 cF>o
//int [] counts = ps.executeBatch();⑶ NY|hE@{2.
conn.commit(); cbl>:ev1h
}catch(Exception e){ _D$1CaAYo
e.printStackTrace(); +;4;~>Y
} finally{ xT(0-o*
try{ e+)y6Q=
if(ps!=null) { rgDl%X2B
ps.clearParameters(); >@Pw{Zh$
ps.close(); %J Jp/I
ps=null; K+"3He
} g)=$zXWhP
}catch(SQLException e){} bg|dV
DBUtils.closeConnection(conn); f@[)*([
} %a
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} -*Tf.c
public long getLast(){ '#SZ|Rr6tX
return lastExecuteTime; JI
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} Jg)( F|>o
public void run(){ $@O?
long now = System.currentTimeMillis(); eK5~YM:o
if ((now - lastExecuteTime) > executeSep) { ug.|ag'R
//System.out.print("lastExecuteTime:"+lastExecuteTime); g/}d> 6
//System.out.print(" now:"+now+"\n"); ^VW]Qr!
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); /GX>L)
lastExecuteTime=now; ^4NRmlb
executeUpdate(); .)=*Yr M
} :aBm,q9i:}
else{ TQb@szp:|
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); C#e :_e]
} QUaV;6
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} +~
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} u80C>sQ
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 OQ4Pk/-'
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类写好了,下面是在JSP中如下调用。 ||fw!8E
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<% ^M%P43
CountBean cb=new CountBean(); ?PqkC&o[q
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); ZjY,k
CountCache.add(cb); ^$}O?y7O
out.print(CountCache.list.size()+"<br>"); k`&FyN^)
CountControl c=new CountControl(); }V*?~.R
c.run(); `Tf}h8*
out.print(CountCache.list.size()+"<br>"); ` &bF@$((
%>