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: Zd%k*BC
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CountBean.java ]L.O8
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/* 3AtGy'NTp
* CountData.java r.&Vw|*>
* ]IQ&>z}<
* Created on 2007年1月1日, 下午4:44 YQvD|x
* V#$RR!X'
* To change this template, choose Tools | Options and locate the template under A2Ed0|B y
* the Source Creation and Management node. Right-click the template and choose z (wc0I
* Open. You can then make changes to the template in the Source Editor. x.6:<y
*/ ibk6|pp
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package com.tot.count; K#d`Hyx
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/** 9ULQrq$?
* S!CC
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* @author WIxy}3_to
*/ qS$Ox?Bw#u
public class CountBean { (NU
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private String countType; V! A~K
int countId; `5.'_3
/** Creates a new instance of CountData */ ^A/k)x6
public CountBean() {} #&aqKVY
public void setCountType(String countTypes){ 3z?> j]
this.countType=countTypes; B%b4v
} u'DRN,h+
public void setCountId(int countIds){ D?_Zl;bQ'^
this.countId=countIds; }@+0/W?\.
} YnAm{YyI
public String getCountType(){ 5coyr`7mP
return countType; 7(8;to6(
} <{cQM$#
public int getCountId(){ E6ElNgL
return countId; hx %v+/
} t\,PB{P:J
} m}t`FsB.
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CountCache.java k$R-#f;
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/* nRS} }6Q
* CountCache.java
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* a~}OZ&PG
* Created on 2007年1月1日, 下午5:01 oW*16>IN9l
* 0R'?~`aTt
* To change this template, choose Tools | Options and locate the template under 6SkaH<-&K
* the Source Creation and Management node. Right-click the template and choose d.d/<
* Open. You can then make changes to the template in the Source Editor. vJ[^K
*/ 6ojo :-%Vf
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package com.tot.count; ChPmX+.i_
import java.util.*; v MH
/** .}TZxla0Zr
* )'#A$ Fj
* @author WlC:l
*/ k"iOB-@B+
public class CountCache { *fS"ym@
public static LinkedList list=new LinkedList(); 3$>1FoSk
/** Creates a new instance of CountCache */ 6Y?|w 3f
public CountCache() {} |N 7M^
public static void add(CountBean cb){ N
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if(cb!=null){ c9u`!'g`i
list.add(cb); | rtD.,m
} Yu^4VXp~M%
} ~Otoqu|
} mnX2a
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CountControl.java giw &&l=_
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/* K;H&n1
* CountThread.java nT$SfGFj8
* Hd ={CFip
* Created on 2007年1月1日, 下午4:57 @,my7?::oM
* CxW>~O:
* To change this template, choose Tools | Options and locate the template under ^%{7}g&$u
* the Source Creation and Management node. Right-click the template and choose T_5H&;a
* Open. You can then make changes to the template in the Source Editor. kv{za4,&
*/ mL{6L?
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package com.tot.count; uh>; 8
import tot.db.DBUtils; q{LF>Wi
import java.sql.*; G}raA%
/** Z0", !6nS
* R.1.)P[
* @author ,<P
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*/ 4p;`C
public class CountControl{ :J&oX
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private static long lastExecuteTime=0;//上次更新时间 Ka
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private static long executeSep=60000;//定义更新间隔时间,单位毫秒 MH\dC9%p
/** Creates a new instance of CountThread */ \V~eVf;~
public CountControl() {} Moza".fiN
public synchronized void executeUpdate(){ "`e{/7I
Connection conn=null; 2-EIE4ds
PreparedStatement ps=null; `l[c_%Bm
try{ D'DfJwA
conn = DBUtils.getConnection(); !M1"b;
conn.setAutoCommit(false); 3,qr-g|;jM
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); ;$wVu|&
for(int i=0;i<CountCache.list.size();i++){ !?h;wR
CountBean cb=(CountBean)CountCache.list.getFirst(); >SHhAEF
CountCache.list.removeFirst(); iz PDd{[
ps.setInt(1, cb.getCountId()); z$. 88^
ps.executeUpdate();⑴ `dN@u@[\ks
//ps.addBatch();⑵ Om2d.7S
} ?NsW|w_
//int [] counts = ps.executeBatch();⑶ WP'!*[z
conn.commit(); kxhWq:[c
}catch(Exception e){ ;dgp+
e.printStackTrace(); 7[XRd9a5(
} finally{ -C]5>& W
try{ >KhOz[Zg
if(ps!=null) { :':s@gqr
ps.clearParameters(); 9qzHS~l
ps.close(); WW~sNC\3`(
ps=null; r[iflBP
} 6O! 2P
}catch(SQLException e){} i<Zc"v;
DBUtils.closeConnection(conn); VjZ|$k
} Qpc__dA\
} Q/0Tj]D
public long getLast(){ 7;wd(8
return lastExecuteTime; `|&O*`
} @lr ztM
public void run(){ -x`@6
long now = System.currentTimeMillis(); Pu$Tk|
if ((now - lastExecuteTime) > executeSep) { ;iL#7NG-R
//System.out.print("lastExecuteTime:"+lastExecuteTime); X\qNG]
//System.out.print(" now:"+now+"\n"); +a{1)nCXe
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); #.)0xfGW)n
lastExecuteTime=now; RMu~l@
executeUpdate(); -k e's
} 'zuIBOH`j3
else{ 1\2no{Vh
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); >U27];}y
} fJ!R6D
} fuf"Ae
} `Eo.v#<
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 Btn]}8K
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类写好了,下面是在JSP中如下调用。 (gWm,fI
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<% 56kI
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CountBean cb=new CountBean(); =MDysb&:
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); B*Dz{a^.:
CountCache.add(cb); oQ[f,7u
out.print(CountCache.list.size()+"<br>"); ;+hH
CountControl c=new CountControl(); jasy<IqT!{
c.run(); K`fuf=
out.print(CountCache.list.size()+"<br>"); =$JET<(
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