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: [IX!3I[J]
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CountBean.java 9S`b7U=P
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/* g0U\AN
* CountData.java X_yU"U
* :BiR6>1:
* Created on 2007年1月1日, 下午4:44 iV$75Atk
* Cl){sP=8W
* To change this template, choose Tools | Options and locate the template under Yl3PZ*#@ Q
* the Source Creation and Management node. Right-click the template and choose (B4A$t
* Open. You can then make changes to the template in the Source Editor. >LZ)<-Mk
*/ 'wHkE/83
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package com.tot.count; JH,fg K+[
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/** ?d'9TOlD
* x"=q+sA
* @author ~ZIRCTQ"
*/ MPw7!G(qj
public class CountBean { zb*4Nsda:
private String countType; }Bg<Fm
int countId; icbYfgQ
/** Creates a new instance of CountData */ YZ+g<HXB
public CountBean() {} $CV'p/^En
public void setCountType(String countTypes){ >dH*FZ:c
this.countType=countTypes; Uv$u\D+@[
} 4B,A+{3yL
public void setCountId(int countIds){ {:j!@w 3
this.countId=countIds; d|HM
} f@X*Tlx^|
public String getCountType(){ `^Sq>R!;
return countType; soCHwiE
} =5#Jsn?U
public int getCountId(){ c.> (/
return countId; fXQRsL8
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} "C|l3X'
} CzbNG^+
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CountCache.java PA[Rhoit,
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/* 'Z9F0l"Nr
* CountCache.java Y3&ecEE
* 73<yrBxp
* Created on 2007年1月1日, 下午5:01 `a9>4
* U Bg_b?k
* To change this template, choose Tools | Options and locate the template under BGjTa.&
* the Source Creation and Management node. Right-click the template and choose WHT%m|yn
* Open. You can then make changes to the template in the Source Editor. \C.@ @4{
*/ n[-!Jp[
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package com.tot.count; W.<<azi
import java.util.*; _QCI<|A
/** (`*wiu+i
* 0_.hU^fP
* @author tfQq3 #
*/ (HxF\#r?
public class CountCache { ^%^0x'"
public static LinkedList list=new LinkedList(); ?V)6`St#C
/** Creates a new instance of CountCache */ k,(_R=
public CountCache() {} 2"^9t1C2
public static void add(CountBean cb){ xo+z[OIlF
if(cb!=null){ 1MSu])
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list.add(cb); G-<~I#k
} aC`
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} vRs5-T
} {P+[CO
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CountControl.java g{(nt5|^l
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/* z$b!J$A1
* CountThread.java _XPc0r:?>
* bq]a8tSB
* Created on 2007年1月1日, 下午4:57 9\2&6H
* >S]')O$c
* To change this template, choose Tools | Options and locate the template under s9>!^MzBK
* the Source Creation and Management node. Right-click the template and choose b<7f:drVC
* Open. You can then make changes to the template in the Source Editor. //|Vj | =
*/ A@r,A?(
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package com.tot.count; '~0&m]N
import tot.db.DBUtils; E
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import java.sql.*; i2E7$[
/** !C?z$5g
* l<?wB|1'
* @author <Z;BB)I&C`
*/ TH &B9
public class CountControl{ R2@u[
private static long lastExecuteTime=0;//上次更新时间 ,~#hHhR_
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 {{\HU0g>&
/** Creates a new instance of CountThread */ u!W00;`L
public CountControl() {} 3OlY Ml
public synchronized void executeUpdate(){ I4'j_X
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Connection conn=null; '>BHwc
PreparedStatement ps=null; $P_Y8:
try{ QTH yH
conn = DBUtils.getConnection(); |Oe6OCPf
conn.setAutoCommit(false); }{J8U2])k
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); &3V4~L1aEg
for(int i=0;i<CountCache.list.size();i++){ g,nE iL
CountBean cb=(CountBean)CountCache.list.getFirst(); XJ9>a-{
CountCache.list.removeFirst(); 2Z~ofrj
ps.setInt(1, cb.getCountId()); gN%R-e0
ps.executeUpdate();⑴ `Ec+i
//ps.addBatch();⑵ MZ'HMYed
} ZUycJ-[
//int [] counts = ps.executeBatch();⑶ [aC(Ga}
conn.commit(); cf9y0
}catch(Exception e){ {;U:0BPI3
e.printStackTrace(); 3B+Rx;>h
} finally{ iKwVYL
try{ \=)h6AG
if(ps!=null) { r+Y1m\
ps.clearParameters(); x{E[qH_1Fm
ps.close(); d<o
ps=null; &BkNkb 0
} =RA6 p
}catch(SQLException e){} aF:LL>H
DBUtils.closeConnection(conn); XJ"9D#"a>
} q2y:bqLWl
} @p;4g_F
public long getLast(){ .;'xm_Gw<
return lastExecuteTime; AO6;aT
} jo;n~>3P
public void run(){ <S
qbj;
long now = System.currentTimeMillis(); b~}}{fm&f
if ((now - lastExecuteTime) > executeSep) { s6I]H
//System.out.print("lastExecuteTime:"+lastExecuteTime); Ts\7)6|F
//System.out.print(" now:"+now+"\n"); 6C:Lq%}
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); )'JSu=Ej
lastExecuteTime=now; 6x 0>E^~
executeUpdate(); hjE9[{K
} 1K>4i. X
else{ Rjf|
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); 8'y|cF%U
} 8Bhng;jX
} 4J s>yP
} r"+
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//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 kcle|B
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类写好了,下面是在JSP中如下调用。 t%)L8%Jr
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<% ]#nAld1cmy
CountBean cb=new CountBean(); <FP-]R)
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); Xp'KQ1w)
CountCache.add(cb); f]Vz !hM~
out.print(CountCache.list.size()+"<br>"); N|DY)W
CountControl c=new CountControl(); x{rt\OT
c.run(); sb1/4u/W
out.print(CountCache.list.size()+"<br>"); HwHI$IB
%>