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: 3kMiC$
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CountBean.java `3-j%H2R
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/* >XF@=Jp
* CountData.java LHz{*`22q
* |&JL6hN
* Created on 2007年1月1日, 下午4:44 L0Cf@~k
* /iK )tl|X
* To change this template, choose Tools | Options and locate the template under ZttL*KK
* the Source Creation and Management node. Right-click the template and choose _W+TZa@_
* Open. You can then make changes to the template in the Source Editor. rW^&8E[
*/ +uA<g`4
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package com.tot.count;
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/** =aCv
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* aE"t['
* @author ~$$V=$&
*/ !m;VWGl*
public class CountBean { p,+~dn;=
private String countType; l>ttxYBa<d
int countId; Qi%A/~
/** Creates a new instance of CountData */ H{BjxZ~)
public CountBean() {} %lPP1
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public void setCountType(String countTypes){ ]k8XLgJ
this.countType=countTypes; ZBGI_9wZ
} oAL-v428
public void setCountId(int countIds){ JTC&_6
this.countId=countIds; TCEbz8ql
} P7o6B,9
public String getCountType(){ F
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return countType; %>.v[d1c
}
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public int getCountId(){ +G~b-}
return countId; #k6;~
} X[w9~t$\
} -zkB`~u_
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CountCache.java QNo}nl/N
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/* tx@Q/ou`\P
* CountCache.java pmS=$z;I
* 5v3B8 @CsA
* Created on 2007年1月1日, 下午5:01 n RGH58
* $`
* To change this template, choose Tools | Options and locate the template under >C i=H(8vN
* the Source Creation and Management node. Right-click the template and choose "$)2|
* Open. You can then make changes to the template in the Source Editor. 1a<,/N}}t
*/ ^2=zp.)
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package com.tot.count; 4-m%[D
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import java.util.*; 3FdoADe{{
/** j% nd
* ~i
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* @author y8L:nnSj
*/ VltWY'\Wu;
public class CountCache { YJ9_cA'A
public static LinkedList list=new LinkedList(); 5E@V@kw
/** Creates a new instance of CountCache */ qg O)@B+
public CountCache() {} Z-Uq89[HZ
public static void add(CountBean cb){ %%_90t
if(cb!=null){ zumRbrz
list.add(cb); M3Z yf
} 6k[u0b`
} S `[8TZ
} aX|`G]PhdI
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CountControl.java _Sg29qFK
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/* _EY:vv
* CountThread.java H(AYtnvB
* 1pn167IQL
* Created on 2007年1月1日, 下午4:57 .D) }MyKnu
* rQWft r^
* To change this template, choose Tools | Options and locate the template under JUE>g8\b
* the Source Creation and Management node. Right-click the template and choose uPqPoI>N!
* Open. You can then make changes to the template in the Source Editor. w+}dm^X
*/ 0Zq"-
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package com.tot.count; eAqQ~)8^
import tot.db.DBUtils; l YhwV\3
import java.sql.*; O<Kr6+
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/** n Au>i<
* Rl(b tr1w
* @author XBc+_=)$
*/ %*uqtw8
public class CountControl{ uJWX7UGuz
private static long lastExecuteTime=0;//上次更新时间 HGKm?'['
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 =19]a
/** Creates a new instance of CountThread */ "P|G^*"~2
public CountControl() {} d0xV<{,-
public synchronized void executeUpdate(){ @@5u{K
Connection conn=null; `A'*x]l
PreparedStatement ps=null; X#o:-FKf
try{ &K4o8Qz
conn = DBUtils.getConnection(); A=])pYE1
conn.setAutoCommit(false); 8RK\B%UW
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); QdRMp
n}q
for(int i=0;i<CountCache.list.size();i++){ JDP#tA3
CountBean cb=(CountBean)CountCache.list.getFirst(); JWBWa-
CountCache.list.removeFirst(); s?2;u p*D
ps.setInt(1, cb.getCountId()); Ky DBCCOv
ps.executeUpdate();⑴ _ %P%~`?!
//ps.addBatch();⑵ F 6Ol5
} u
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//int [] counts = ps.executeBatch();⑶ %cv%u6 b
conn.commit(); ZLV~It&)
}catch(Exception e){ R|vF*0)>W
e.printStackTrace(); ^TjFR*S'E
} finally{ <omz9d1
try{ m/ukH{H1%
if(ps!=null) { c{<3\
ps.clearParameters(); |joGrWv4
ps.close(); r[lHYO
ps=null; GwvxX&P
} J
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}catch(SQLException e){} <HD/&4$[
DBUtils.closeConnection(conn); K{iYp4pU
} w\M_3}
} q&M;rIo?
public long getLast(){ nO/5X>A,Zw
return lastExecuteTime; <@yyx7
} vxgm0ZOMN
public void run(){ $~-j-0
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long now = System.currentTimeMillis(); yTEuf@
if ((now - lastExecuteTime) > executeSep) { 7KEGTKfW
//System.out.print("lastExecuteTime:"+lastExecuteTime); I2 Kb.`'!
//System.out.print(" now:"+now+"\n"); J@5 OZFMZ
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); K%g\\uo
lastExecuteTime=now; OlK2<<
executeUpdate(); lojn8uL
} {kzM*!g
else{ F,W(H@ ~x
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); H^s SHj
} \uaJw\EZ
} S\,{qhd
} ff0B*0
//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 Fc]#\d6
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类写好了,下面是在JSP中如下调用。 l>]M^=,&7
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<% O~S}u
CountBean cb=new CountBean(); }_;nln?t(
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); N.<hZ\].=
CountCache.add(cb); zknD(%a
out.print(CountCache.list.size()+"<br>"); cnsGP*w
CountControl c=new CountControl(); WS(c0c
c.run(); &zT~3>2
out.print(CountCache.list.size()+"<br>"); k9,"`dk@
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