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: kpsus \T
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CountBean.java ;26a8g(
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/* 36,qh.LKn
* CountData.java (~?P7RnU%
* gG1%.q
* Created on 2007年1月1日, 下午4:44 Xt(w+
* CN#`m]l.
* To change this template, choose Tools | Options and locate the template under sg;Gk/]
* the Source Creation and Management node. Right-click the template and choose &[`p qX
* Open. You can then make changes to the template in the Source Editor. |eAl!k
*/ B=%cXW,
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package com.tot.count; l}j5EWe
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/** SouPk/-B80
* @aN<nd`q)
* @author %a&Yt
*/ .e!dEF)D
public class CountBean { 3+u11'0=t
private String countType; x$QOOE]
int countId; ,'v ]U@WK
/** Creates a new instance of CountData */ (Gf1#,/3~
public CountBean() {} :/c=."z.
public void setCountType(String countTypes){ PaP47>(
this.countType=countTypes; o/@.*Rj>Bg
} 'b]GcAL
public void setCountId(int countIds){ dms R>Q
this.countId=countIds; ..UmbJJ.u
} tu#VZAPW@
public String getCountType(){ sn
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return countType; +v2Fr}
} dy-m9fc6%
public int getCountId(){ &, hhH_W
return countId; 5&D)W>{d
} (s4w0z
} %*>=L$A
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CountCache.java wo5"f}vd#
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/* v3x_8n$C9
* CountCache.java dqwAQ-x
* |G&<@8O
* Created on 2007年1月1日, 下午5:01 \\AufAkJ
* ;f#%0W{":
* To change this template, choose Tools | Options and locate the template under lO3$V JI
* the Source Creation and Management node. Right-click the template and choose
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* Open. You can then make changes to the template in the Source Editor. xbnx*4o0
*/ h-+9Bv]
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package com.tot.count; I7ZY9W(S
import java.util.*; }` E5I&r4
/** Rx<m+=
* {Lwgj7|~
* @author `*mctjSN
*/ jq
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public class CountCache { *kY\,r&!P
public static LinkedList list=new LinkedList(); }dX[u`zQ
/** Creates a new instance of CountCache */ ~McmlJzJG
public CountCache() {} %W~Kx_
public static void add(CountBean cb){ jku_0Q0*?
if(cb!=null){ vQ>x5\r5O_
list.add(cb); 0+jR,5|
} X|^E+
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} ,+-l1GpL
} 8u
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CountControl.java _)
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/* U+>!DtOYK
* CountThread.java "aIiW VQ
* td%]l1
* Created on 2007年1月1日, 下午4:57 VC5LxA0{
* j9)P3=s
* To change this template, choose Tools | Options and locate the template under Fi vgOa
* the Source Creation and Management node. Right-click the template and choose 6d& dB
* Open. You can then make changes to the template in the Source Editor. 3`uv/O2~i
*/ )8VrGg?
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package com.tot.count; 3}e-qFlV8,
import tot.db.DBUtils; CG*eo!Nw
import java.sql.*; };6[Byf
/** nAPSs]D
* {R%v4#nk
* @author Kmc*z (Q
*/ dP63bV
public class CountControl{ NBEcx>pma
private static long lastExecuteTime=0;//上次更新时间 <aR9,:
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 u>o<ua
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/** Creates a new instance of CountThread */ c,pR+DP
public CountControl() {} <^q4^Q[
public synchronized void executeUpdate(){ 2eo]D?}
Connection conn=null; LsH&`G^<
PreparedStatement ps=null; A]L;LkEM
try{ 7ZarXv
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conn = DBUtils.getConnection(); j hf%ze
conn.setAutoCommit(false); H^z6.!$m
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); mz$)80ly
for(int i=0;i<CountCache.list.size();i++){ Zz}Wg@&
CountBean cb=(CountBean)CountCache.list.getFirst(); >Eg/ir0
CountCache.list.removeFirst(); Oya:{d&=
ps.setInt(1, cb.getCountId()); oE\Cwd
ps.executeUpdate();⑴ >
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//ps.addBatch();⑵ 2k;>nlVxX
} $*w]]b$Dn
//int [] counts = ps.executeBatch();⑶ s ;EwAd(
conn.commit(); .l5y+a'
}catch(Exception e){ 0t[|3A~Q
e.printStackTrace(); 2z+Vt_%
} finally{ kDI(Y=Fg
try{ kx&Xk0F_g
if(ps!=null) { t`=TonLb8
ps.clearParameters(); XgL-t~_
ps.close(); jkCa2!WQ'i
ps=null; ]D_"tQ?i
} qn)
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}catch(SQLException e){} |s[kY
DBUtils.closeConnection(conn); (3a]#`Q
} OXcQMVa
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} k+#6
public long getLast(){ ;D.a |(Q
return lastExecuteTime; x}v]JEIf[Q
}
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public void run(){ lZ]x #v
long now = System.currentTimeMillis(); tQ0iie1Ys
if ((now - lastExecuteTime) > executeSep) { ?.Mw
//System.out.print("lastExecuteTime:"+lastExecuteTime); dd1CuOd6(1
//System.out.print(" now:"+now+"\n"); KG9h
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// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); r+%:rFeX
lastExecuteTime=now; Ua0fs|t1v
executeUpdate(); '-C%?*ku
} sjl(
else{ +e
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//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); $>Md]/I8
} Ilt!O^
} q"BM*:W
} Wmri%
//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 >%Rb}Ki4
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类写好了,下面是在JSP中如下调用。 >K:| +XbH
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<% );EW(7KeL
CountBean cb=new CountBean(); }]O*
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cb.setCountId(Integer.parseInt(request.getParameter("cid"))); OXu*wl(z
CountCache.add(cb); pT3p!/pl3
out.print(CountCache.list.size()+"<br>"); ;Z>u]uK4+
CountControl c=new CountControl(); .axJ '*~W
c.run(); 7>
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out.print(CountCache.list.size()+"<br>"); `;KU^dH
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