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: cS|W&IH1
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CountBean.java M;X}v#l|XI
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/* G/Yqvu,2!
* CountData.java #
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* .gwT?O,
* Created on 2007年1月1日, 下午4:44 CVgVyy^
* OYIH**?
* To change this template, choose Tools | Options and locate the template under H3|x
* the Source Creation and Management node. Right-click the template and choose w2]]##J
* Open. You can then make changes to the template in the Source Editor. Kb#Z(C9
*/ csv;u'
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package com.tot.count; mm`yu$9gbP
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/** U'xmn$O
* Z=144n 1
* @author pTcN8E&Unz
*/ D7,{p2<2T
public class CountBean { u`Zj~t
private String countType; m@c\<-P
int countId; lDtl6r/
/** Creates a new instance of CountData */ )WF*fcx{
public CountBean() {} KZsJ_t++!W
public void setCountType(String countTypes){ K1|xatx1V
this.countType=countTypes; }ILg_>uq[
} $s9YU"
public void setCountId(int countIds){ :}~B;s0M\
this.countId=countIds; }FAO.
} ,a@jg&Mb]
public String getCountType(){ iFB {a?BE
return countType; cY%6+uJ1
} IaYy5Rw
public int getCountId(){ 2u^/yl
return countId; /-C6I:
} uU`Mq8)R
} FP h1 }qS
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CountCache.java _*dUH5
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/* lZhd^69y
* CountCache.java j?oh~7Ki
* LLW\1 cxi
* Created on 2007年1月1日, 下午5:01 r|0wIpi6Q
* F*/J`l
* To change this template, choose Tools | Options and locate the template under =bl6:
* the Source Creation and Management node. Right-click the template and choose #BwkbOgr
* Open. You can then make changes to the template in the Source Editor. 0r'<aA`=I
*/ aiwKkf`\
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package com.tot.count; 6#Afj0
import java.util.*; {);<2]o| 6
/** -ZE]VO*F
* M@78.lPS
* @author L[.RV*sL
*/ r2xIbZ
public class CountCache { l]__!X
public static LinkedList list=new LinkedList(); 222Mm/QN
/** Creates a new instance of CountCache */ t8upS
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public CountCache() {} Yuqt=\? #
public static void add(CountBean cb){ fg0zD:@rA
if(cb!=null){ Qj',&b
list.add(cb); ?LA`v_
} `@Tl7I\
} `l`)Cs;a
} Ld:U~M-
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CountControl.java nkTu/)or
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/* je^=g nq
* CountThread.java 72{Ce7J4
* OykYXFv*
* Created on 2007年1月1日, 下午4:57 3=xN)j#B
* ?*2Uw{~}
* To change this template, choose Tools | Options and locate the template under zDx*R3%
* the Source Creation and Management node. Right-click the template and choose };s8xGW:k3
* Open. You can then make changes to the template in the Source Editor. A1V^Gi@i
*/ {S5HH"
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package com.tot.count; q[MZSg
import tot.db.DBUtils; z ,q1TU9
import java.sql.*; M7g6m
/** S{F'k;x/5
* U%E364;F
* @author 3"y,UtKGa
*/ ] B3\IT
public class CountControl{ o!>h
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private static long lastExecuteTime=0;//上次更新时间 G[M{TS3&Ds
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 wwD?i.3
/** Creates a new instance of CountThread */ `c%{M4bF\
public CountControl() {} 2qxede
public synchronized void executeUpdate(){ $`Hb-
Connection conn=null; pu?D^h9/
PreparedStatement ps=null; b?{ \t;
try{ N9=1<{Z
conn = DBUtils.getConnection(); eY#_!{*Wn
conn.setAutoCommit(false); @<,YUp,%S
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); xY94v
for(int i=0;i<CountCache.list.size();i++){ oVYW'~OID
CountBean cb=(CountBean)CountCache.list.getFirst(); =UMqa;\K
CountCache.list.removeFirst(); 65||]l
ps.setInt(1, cb.getCountId()); 6A,-?W'\
ps.executeUpdate();⑴ 2E*h,Mo
//ps.addBatch();⑵ mel(C1b"j/
} `37$YdX
//int [] counts = ps.executeBatch();⑶ HH3Ln+AWg_
conn.commit(); 7ajkp+E6
}catch(Exception e){ .`Rju|l
e.printStackTrace(); Vp
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} finally{ <Gkmk?x`A
try{ + Ssu^>D
if(ps!=null) { tEE4"OAy
ps.clearParameters(); G~N$bF^R)
ps.close(); !au%D?w
ps=null; N497"H</
} I`
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}catch(SQLException e){} qGrUS_~q*
DBUtils.closeConnection(conn); s%l`XW;v
} 5`H.{4@
} 1sN >U<
public long getLast(){ _q<Ke/
return lastExecuteTime; 1'Y7h;\~\
} QdtGFY4f,
public void run(){ &h_do8R
long now = System.currentTimeMillis(); g:]X '%Ub
if ((now - lastExecuteTime) > executeSep) { B A(PWX`H
//System.out.print("lastExecuteTime:"+lastExecuteTime); " }oH3L
//System.out.print(" now:"+now+"\n"); =LHz[dSL
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); {]V+C=`
lastExecuteTime=now; k2Y *
executeUpdate(); S"skKh4w
} ~![J~CkPS
else{ FvVR \a
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); Xah-*]ET
} ^a{cK
} `D~wY^q{
} 5KI lU78
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 0AWOdd>.
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类写好了,下面是在JSP中如下调用。 wi$,Y.:
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<% *p Q'w
CountBean cb=new CountBean(); Vnvfu!>(
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); vE<z0l
CountCache.add(cb); GZCX m+
out.print(CountCache.list.size()+"<br>"); bj$VYS"kY
CountControl c=new CountControl(); 1Q>D^yPI[
c.run(); Y `ySNC
out.print(CountCache.list.size()+"<br>"); E@%9u#
%>