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: 0XV8B
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CountBean.java AD_RU_a9
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/* *x[ZN\$`Y
* CountData.java \.c
* LWG%]m|C
* Created on 2007年1月1日, 下午4:44 &''lOS|
* (tQ#('(w
* To change this template, choose Tools | Options and locate the template under Pf`HF|NI
* the Source Creation and Management node. Right-click the template and choose gA0:qEL\
* Open. You can then make changes to the template in the Source Editor. w|$i<OIi)
*/ OwhMtYq
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package com.tot.count; *?sdWRbu}l
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/** d/I,`
* z ((Y \vP
* @author ;S
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*/ s~N WJ*i
public class CountBean { G 3))3]
private String countType; )l 0\TF
int countId; S ]_iobWK
/** Creates a new instance of CountData */ X@l>mAk
public CountBean() {} 9H^$cM9C
public void setCountType(String countTypes){ a2J01B
this.countType=countTypes; 3>60_:+Zb
} ZDHm@,d
public void setCountId(int countIds){ f(}?Sp_
this.countId=countIds; NDsF<2A4
} X2CpA;#;7l
public String getCountType(){ ?` ?HqR0
return countType; H@ab]&
} p0c*)_a*
public int getCountId(){ )fPN6x/e
return countId; /2 V
} x-0O3IIE
} tzH~[n,
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CountCache.java .gZ1}2GF=
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/* Jz"Yb
* CountCache.java Rr>nka)U
* !vd(WKq
* Created on 2007年1月1日, 下午5:01 b+b].,
* #8xP,2&zf
* To change this template, choose Tools | Options and locate the template under [wp(s2=
* the Source Creation and Management node. Right-click the template and choose Y.>F fL
* Open. You can then make changes to the template in the Source Editor. -8Z;s8ACo
*/
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package com.tot.count; )96tBA%u
import java.util.*; UNK}!>HD
/** _.)6~
* .J?cV;:`
* @author V{qpha4'P
*/ 94uAt&&b(
public class CountCache { },r9f MJ
public static LinkedList list=new LinkedList(); _x+)Tv
/** Creates a new instance of CountCache */ CEQs}bz
public CountCache() {} JU>F&g/|
public static void add(CountBean cb){ 'YFy6rds
if(cb!=null){ iX]tL:,~i
list.add(cb); LN=6u
} qYba%g9RN(
} x:wv#Wh:l7
} SM?rss.=
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CountControl.java l$1
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/* 86 $88`/2
* CountThread.java O0`o0!=P
* <m"fzT<"
* Created on 2007年1月1日, 下午4:57 zDD
* zE,1zBS<
* To change this template, choose Tools | Options and locate the template under 7{W#i<W
* the Source Creation and Management node. Right-click the template and choose ?WEKRl
* Open. You can then make changes to the template in the Source Editor. B>]4NF\)H9
*/ M9C
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package com.tot.count; J?R\qEq%
import tot.db.DBUtils; oy[>`qyz
import java.sql.*; AHB_[i'>7
/** z^,P2kqK_
* K;L6<a A#
* @author !c2<-3e
*/ O su 75@3
public class CountControl{ $^K12Wcp-
private static long lastExecuteTime=0;//上次更新时间 lVptA3F
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 xR~9|H9a
/** Creates a new instance of CountThread */ _keI0ML-#
public CountControl() {} 8x~'fzf;Sq
public synchronized void executeUpdate(){ 9*Z!=Y#4,
Connection conn=null; f%[0}.wp
PreparedStatement ps=null; U;w|
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try{ Q8h0:Q
conn = DBUtils.getConnection(); q1Sr#h|
conn.setAutoCommit(false); dy"7Wl]hi7
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); .ri?p:a}w
for(int i=0;i<CountCache.list.size();i++){ o;[cApiQ,2
CountBean cb=(CountBean)CountCache.list.getFirst(); qu`F,OG
CountCache.list.removeFirst(); e'dx
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ps.setInt(1, cb.getCountId()); ]H-5
ps.executeUpdate();⑴ (F+]h]KSi
//ps.addBatch();⑵ 9O4\DRe5c
} |s!<vvp]
//int [] counts = ps.executeBatch();⑶ 16-1&WuY@
conn.commit(); Z,_EhEm
}catch(Exception e){ Y 8Dn&W
e.printStackTrace(); nvInq2T1
} finally{ ]^>RBegJBO
try{ \Dx5= Lh
if(ps!=null) { GeFu_7u!|
ps.clearParameters(); ;659E_y>
ps.close(); hd>_K*oH
ps=null; =WEWs4V5A
} TQL_K8k@_
}catch(SQLException e){} P;bOtT --
DBUtils.closeConnection(conn); wl Nl|+ K
} .VA'W16
} KN<KZM
public long getLast(){ tq.g4X ;_
return lastExecuteTime; :"Gd;~p.
} Sp-M:,H3H
public void run(){ Yu+;vjbK-
long now = System.currentTimeMillis(); 19]O;
if ((now - lastExecuteTime) > executeSep) { *|B5,Ey
//System.out.print("lastExecuteTime:"+lastExecuteTime); gR76g4|=;
//System.out.print(" now:"+now+"\n"); u
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// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); W<\*5oB%H
lastExecuteTime=now; lz:+y/+1
executeUpdate(); __Egr@
} gg?O0W{
else{ GswV/V+u
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); R+<M"LriR&
} =<.h.n
} j"Z9}F@
} 5E!Wp[^
//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 ?WBA:?=$58
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类写好了,下面是在JSP中如下调用。 AVO$R\1YR
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<% 7<zI'^l
CountBean cb=new CountBean(); QI4a@WB]ok
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); NOQSL T=
CountCache.add(cb); 2PViY,V|
out.print(CountCache.list.size()+"<br>"); &`B
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CountControl c=new CountControl(); mQ=nU
c.run(); S]<%^W'
out.print(CountCache.list.size()+"<br>"); OV`#/QL
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