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: /4+zT?f
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CountBean.java |pMP-
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/* !{(crfXB
* CountData.java <~v4BiQ3l^
* 6MU;9|&
* Created on 2007年1月1日, 下午4:44 +:70vZc:V@
* A>S7Ap4z>
* To change this template, choose Tools | Options and locate the template under 17;9> *O'
* the Source Creation and Management node. Right-click the template and choose 7T!t*sSO'
* Open. You can then make changes to the template in the Source Editor. eW3?3l`fvt
*/ {(F}SF{
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package com.tot.count; JW2f 6!b
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/** l$l6,OzS@
* tx+P@9M_Aq
* @author S}0-2T[
*/ &A/b9GW^-
public class CountBean { <.BY=z=H
private String countType; `2V{]F
int countId; 8<Yv:8%B6
/** Creates a new instance of CountData */ egfd=z=2un
public CountBean() {} 4PU@W o
public void setCountType(String countTypes){ D0S^Msk9L
this.countType=countTypes; )ytP$,r![S
} :AuK Q`c
public void setCountId(int countIds){ 1{cF/ :o
this.countId=countIds; lSd tw b
} j 7O!uUQQ
public String getCountType(){ #%OS=.V
return countType; v!<FeLW
} TOSk+2P
public int getCountId(){ o2]Np~`g,
return countId; +mKII>{
} ;r]!
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} a #p`l>rx
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CountCache.java aGE}
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/* PT&qys2k
* CountCache.java 0s}gg[lj
* {ynI]Wj`L
* Created on 2007年1月1日, 下午5:01 +Bt%W%_X
* Sv>CVp*
* To change this template, choose Tools | Options and locate the template under PqyR,Bcx0
* the Source Creation and Management node. Right-click the template and choose Y1qbu~!
* Open. You can then make changes to the template in the Source Editor. `r\/5|M
*/ D`B*+
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package com.tot.count; | -Gb Hfz
import java.util.*; 0BjP|API
/** QT1oU P#*
* Q4N0j' QA
* @author MfFmJ7>Bg
*/ 1O)m(0tb[
public class CountCache { %JA^b5''
public static LinkedList list=new LinkedList(); OH
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/** Creates a new instance of CountCache */ W7~OU(}[`
public CountCache() {} Y~lOkH[z
public static void add(CountBean cb){ pg<cvok
if(cb!=null){ P{2ED1T\
list.add(cb); 6Ol)SQE,
} !@+4&B=
} ?$/W3Xn0%
} w0<1=;_%
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CountControl.java EWVn*xl?
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/* <<YH4}wZ
* CountThread.java |*]<*qnZt
* p8&rl|z|
* Created on 2007年1月1日, 下午4:57 1x+w|h
* Zjc0R
* To change this template, choose Tools | Options and locate the template under !|"LAr9u
* the Source Creation and Management node. Right-click the template and choose "88<{x L
* Open. You can then make changes to the template in the Source Editor. _XI,z0(
*/ -Zg@#H
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package com.tot.count; YB]^Y^" e
import tot.db.DBUtils; H}1XK|K3#H
import java.sql.*; UM+g8J{$*;
/** >-`-D=!V
* 6?0QzSpfC#
* @author cI<T/~P
*/ c+1<3)Q<
public class CountControl{ /9-kG
private static long lastExecuteTime=0;//上次更新时间 DPl &e-`
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 _]+
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/** Creates a new instance of CountThread */ }.<]A
public CountControl() {} s8r[U, }(
public synchronized void executeUpdate(){ }\ya6Gi8
Connection conn=null; {E1^Wn1M
PreparedStatement ps=null; dJ{'b'#
try{ r"KW\HN8
conn = DBUtils.getConnection(); C7
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conn.setAutoCommit(false); ITU6Eq
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); anUH'mcK*
for(int i=0;i<CountCache.list.size();i++){ {=y~O
CountBean cb=(CountBean)CountCache.list.getFirst(); :C#(yp
CountCache.list.removeFirst(); K7
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ps.setInt(1, cb.getCountId()); >>h0(G|
ps.executeUpdate();⑴ XO/JnJ^B
//ps.addBatch();⑵ gvxOo#8]
} QUc&f+~
//int [] counts = ps.executeBatch();⑶ nN[QUg
conn.commit(); ^JB5-EtL(
}catch(Exception e){ @ c%h fI
e.printStackTrace(); TaTw,K|/
} finally{ O-<nLB!Wf
try{ =l}XKl->
if(ps!=null) { DDU)G51>d
ps.clearParameters(); FWpb5jc)3
ps.close(); 6
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ps=null; W
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} R%r<AL5kJk
}catch(SQLException e){} ItQ3|-^
DBUtils.closeConnection(conn); B%Z ,Xjq
} G5zsId
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} FS6ZPjG)
public long getLast(){ hKQg:30<
return lastExecuteTime; ,N2|P:x
} E#M4{a1
public void run(){ V#d8fRm
long now = System.currentTimeMillis(); _R|8_#yM
if ((now - lastExecuteTime) > executeSep) { _/a8X:[(
//System.out.print("lastExecuteTime:"+lastExecuteTime); Ap%tm)@1
//System.out.print(" now:"+now+"\n"); 2E=vMAS
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); inv 5>OeG
lastExecuteTime=now;
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executeUpdate(); ADlLodG
} "@+r|x
else{ `bRt_XGPmF
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); os`#:Ao5
} +"SYG
} rY(h }z
} J[4IO
//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 |gJI}"T
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类写好了,下面是在JSP中如下调用。 uI_h__
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<% .s>PDzM$
CountBean cb=new CountBean(); t3FfPV!P"
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); bl`vT3
CountCache.add(cb); >{w"aJ" F
out.print(CountCache.list.size()+"<br>"); ^/v!hq_#%&
CountControl c=new CountControl(); )|i]"8I
c.run(); :~dI2e\:
out.print(CountCache.list.size()+"<br>"); + |d[q?
%>