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: e K1m(E.=
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CountBean.java ~_db<!a
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/* Q(5:~**I
* CountData.java c9TAV,/fF*
* ,XG|oo-
* Created on 2007年1月1日, 下午4:44 ~wf~bzs
* gpK_0?%
* To change this template, choose Tools | Options and locate the template under }t
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* the Source Creation and Management node. Right-click the template and choose dh;Mp E
* Open. You can then make changes to the template in the Source Editor. vDeG20.?Z
*/ +.#S[G
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package com.tot.count; a-A+.7
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/** bC4*w
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* [{p?BTs
* @author iC|6roO!jk
*/ *CY6
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public class CountBean { VWA -?%r
private String countType; M |Q
int countId; 7! b)'W?
/** Creates a new instance of CountData */ g1 Wtu*K3
public CountBean() {} `-K)K<
public void setCountType(String countTypes){ ssX6kgq_(
this.countType=countTypes; JIbzh?$aD
} N<Z)b!o%u
public void setCountId(int countIds){ Z>Kcz^a#
this.countId=countIds; `k{ ff
} *fvI.cKiGP
public String getCountType(){ ]i,Mq
return countType; K jn&
} vi! r8k
public int getCountId(){ Avv
return countId; xL39>PB
} "Yfr"1RmO
} g?A5'o&Yu
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CountCache.java J!A/r<
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/* ;!0.Kk
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* CountCache.java + 1+A3
* ndKvJH 4
* Created on 2007年1月1日, 下午5:01 N1+4bR
* =Y]'5cn{
* To change this template, choose Tools | Options and locate the template under N}}PlGp$
* the Source Creation and Management node. Right-click the template and choose >Oi2gPA
* Open. You can then make changes to the template in the Source Editor. ~aqT~TL_
*/ :@QK}qFP
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package com.tot.count; vSYunI
import java.util.*; p;n3`aVh
/** gf3u0' $
* G&%nF4
* @author y?Hj%,
*/ EvSnZB1 y
public class CountCache { =2;mxJ# o
public static LinkedList list=new LinkedList(); Z/NGv
/** Creates a new instance of CountCache */ e}](6"t`5
public CountCache() {} ')P2O\YS
public static void add(CountBean cb){ cwM#X;FGq
if(cb!=null){ M!&_qj&N,
list.add(cb); +K$5tT6b
} <4l.s
} [D<RV3x9
} /`4v"f0V
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CountControl.java Rm,[D)D^0N
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/* ,<0Rf
* CountThread.java PS_3Oq)
* ibZt2@GB)I
* Created on 2007年1月1日, 下午4:57 9:9N)cNvfX
* 1AV1d%F
* To change this template, choose Tools | Options and locate the template under aW`:)y&f
* the Source Creation and Management node. Right-click the template and choose #/n|@z'
* Open. You can then make changes to the template in the Source Editor. *1|YLy
*/ b"ol\&1
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package com.tot.count; Cbgj@4H
import tot.db.DBUtils; #Acon7Rp
import java.sql.*; }j+~'O4m
/** Hk<X
* 7af?E)}v
* @author f
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*/ 1KeJd&e
public class CountControl{ e={k.y}x}
private static long lastExecuteTime=0;//上次更新时间 M(n<Iu4^_
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 }G>v]bV0V
/** Creates a new instance of CountThread */ uI%N?
public CountControl() {} tyc8{t#Z
public synchronized void executeUpdate(){ EzzTJ>
Connection conn=null; EpRXjz
PreparedStatement ps=null; fkdf~Vb
try{ ePV-yy
conn = DBUtils.getConnection(); ?60>'Xjj
conn.setAutoCommit(false); r5f^WZ$-
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); R(M}0JRm
for(int i=0;i<CountCache.list.size();i++){ Nc
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CountBean cb=(CountBean)CountCache.list.getFirst(); J}x>~?W
CountCache.list.removeFirst(); Jz~+J*r;]A
ps.setInt(1, cb.getCountId()); .yZK.[x4
ps.executeUpdate();⑴ :~\LOKf
//ps.addBatch();⑵ Of1IdE6~
} \w{@u)h
//int [] counts = ps.executeBatch();⑶ gJ]Cq/gC
conn.commit(); "sFW~Y
}catch(Exception e){ ]XmQ]Yit
e.printStackTrace(); s9uL<$,'
} finally{ x7vq?fP0n
try{ $-m@KB
if(ps!=null) { Jb(DJ-&
ps.clearParameters(); !nec 7
ps.close(); zl0;84:H
ps=null; TcR=GR*cJ
} '
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}catch(SQLException e){} 4O$ mR
DBUtils.closeConnection(conn); IeO-O'^&`
} 6a7vlo
}
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public long getLast(){ \BLp-B1s
return lastExecuteTime; -<8B,
} ||R0U@F,
public void run(){ yPSVwe|g
long now = System.currentTimeMillis(); Ynvj;
if ((now - lastExecuteTime) > executeSep) { 9X!ET!
//System.out.print("lastExecuteTime:"+lastExecuteTime); XFtOmY
//System.out.print(" now:"+now+"\n"); DLU[<!C
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); `GPQ((la
lastExecuteTime=now; Q6u{@$(/N
executeUpdate(); xM%
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} _8al
else{ p Z"o@';!
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); Ft3I>=f{
} 6*sw,sU[y
} Ah*wQow
} B#1:Y;Z
//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 %Nl`~Kz9U
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类写好了,下面是在JSP中如下调用。 F{;;
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<% "t=UX
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CountBean cb=new CountBean(); +)zDA:2Wa"
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); :"V ujvFX
CountCache.add(cb); !z?0 :Jg
out.print(CountCache.list.size()+"<br>"); AfN&n= d K
CountControl c=new CountControl(); !Ri
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c.run(); *_PPrx5
out.print(CountCache.list.size()+"<br>"); 0D<TF>M;pn
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