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: T*nP-b
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CountBean.java $,yAOaa
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/* C]p@7"l
* CountData.java axpZ`BUc
* NBHpM}1xtU
* Created on 2007年1月1日, 下午4:44 z0OxJ e
* <v'&Pk<
* To change this template, choose Tools | Options and locate the template under ,J8n}7aI
* the Source Creation and Management node. Right-click the template and choose C!|LGzs0
* Open. You can then make changes to the template in the Source Editor.
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*/ /ywP
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package com.tot.count; _ OC@J*4.
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/** 5VJe6i9;
* X
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* @author a|"Uw
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*/ 0Ni{UV?
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public class CountBean { Fn7OmxfD
private String countType; IzJq:G.
int countId; /0 4US5En
/** Creates a new instance of CountData */ =MMd&
public CountBean() {} A&bj l[s
public void setCountType(String countTypes){ ~`C_B]3|
this.countType=countTypes; z}B39L
} xhOoZ-
public void setCountId(int countIds){
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this.countId=countIds; n{i,`oQ"
} naW!b&:
public String getCountType(){ I{jvUYrKH
return countType; y;uR@{
} 8'HS$J;C
public int getCountId(){ V*{rHp{=p
return countId; Yu>DgMW
} fj))Hnt(|
} 0=#>w_B
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CountCache.java EgU#r@7I
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/* ?)y^ [9
* CountCache.java hg(<>_~
* BUJ\[/
* Created on 2007年1月1日, 下午5:01 _BmObXOp.
* NOuG# P
* To change this template, choose Tools | Options and locate the template under =y4dR#R(\
* the Source Creation and Management node. Right-click the template and choose L_NiU;cr%
* Open. You can then make changes to the template in the Source Editor. R2gV(L(!!
*/ %^pi
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package com.tot.count; :t{~Mi=T
import java.util.*; R<Lf>p>_
/** RI0^#S_{
* :Iv;%a0 -
* @author w8UuwFG?<
*/ /v8Q17O?e
public class CountCache { YR9fw
public static LinkedList list=new LinkedList(); 2t-w0~O
/** Creates a new instance of CountCache */ OegeZV
public CountCache() {} kkF)Tro\
public static void add(CountBean cb){ *[3xc*5F/A
if(cb!=null){ ]~KLdgru_
list.add(cb); ~lys
} 3KkfQ{
} jC9us>b
} lUm(iYv;H
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CountControl.java $'498%K2
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/* HU i?\4
* CountThread.java _1p8(n
* hMDd*<%l
* Created on 2007年1月1日, 下午4:57 <Ep L<K%
* @h%V:c
* To change this template, choose Tools | Options and locate the template under hj [77EEz
* the Source Creation and Management node. Right-click the template and choose 6lSz/V;
* Open. You can then make changes to the template in the Source Editor. :$MOdL[ir
*/ _\ToA9 m
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package com.tot.count; -n|bi cP
import tot.db.DBUtils; <W80A J
import java.sql.*; `Vb
/** `p\=NP!n
* ;sZG=y@
* @author /\I6j;$z
*/ ?Z7`TnG$uf
public class CountControl{ mL{P4a 1xf
private static long lastExecuteTime=0;//上次更新时间 3!"N;Q"
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 q@|+`>h
/** Creates a new instance of CountThread */ Km`
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public CountControl() {} ~~tTr$
public synchronized void executeUpdate(){ Ts5)r(
Connection conn=null; 21uK&nVf^l
PreparedStatement ps=null; :v&[!
try{ 94u{k1d x
conn = DBUtils.getConnection(); zX>W 8P
conn.setAutoCommit(false); ti\
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ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); Zv u6/#
for(int i=0;i<CountCache.list.size();i++){ ef5)z}B
CountBean cb=(CountBean)CountCache.list.getFirst(); };/QK*
CountCache.list.removeFirst(); yn4T!r "
ps.setInt(1, cb.getCountId()); H U|.5tP
ps.executeUpdate();⑴ (vs<Fo|]
//ps.addBatch();⑵ PsY![CPrW
} 9u B?-.
//int [] counts = ps.executeBatch();⑶ _R4}\3}!
conn.commit(); A6N6e\*
}catch(Exception e){ 3Vb4zZsl
e.printStackTrace(); `fu_){
} finally{ aF{_"X2
try{ *o6}>;
if(ps!=null) { WE<?y_0y&
ps.clearParameters(); ;[v!#+yml
ps.close(); {VgE07r
ps=null; LW %AZkAx
} CVj^{||eF
}catch(SQLException e){} 2"Os9 KD
DBUtils.closeConnection(conn); IGdiIhH~2
} z:Ml;y
} =kjKK
public long getLast(){ Ot=jwvw
return lastExecuteTime; $^Fl*:6
} Y[
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public void run(){ ]ss[n.T0*
long now = System.currentTimeMillis(); $*Ucfw1T
if ((now - lastExecuteTime) > executeSep) { p@<Q?
//System.out.print("lastExecuteTime:"+lastExecuteTime); w+M/VsL
//System.out.print(" now:"+now+"\n"); wu41Mz7
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); vCzZjGBY
lastExecuteTime=now; C"hN2Z!CD|
executeUpdate(); kB7vc>@1
} [GwAm>k
else{ uZqL'l+/y
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); DeO-@4+qKd
} U( YAI%O
} *}?[tR5
} wq)*bIv
//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 9^gYy&+>6]
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类写好了,下面是在JSP中如下调用。 o3J#hQrl
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<% <_EKCk
CountBean cb=new CountBean(); Z%t_1t
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); &5CRXf
CountCache.add(cb); 'o AmA=
out.print(CountCache.list.size()+"<br>"); ^&zCPUH
CountControl c=new CountControl(); zj
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c.run(); aukcO;oG<
out.print(CountCache.list.size()+"<br>"); JGs:RD'
%>