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: 4}{HRs?
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CountBean.java |2\6X's
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/* <h2WM (n
* CountData.java =uZ[
* nJ#uz:(w,
* Created on 2007年1月1日, 下午4:44 ~jb6
* #]i*u1
* To change this template, choose Tools | Options and locate the template under 3u7N/OQ(
* the Source Creation and Management node. Right-click the template and choose edqek jh
* Open. You can then make changes to the template in the Source Editor. 8kw`=wSH>
*/ Us'm9 J
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package com.tot.count; Z;bzp3v
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/** c~(+#a
* 3~\mP\/4v
* @author ^o]ZDc
*/ /i$
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public class CountBean { nsqs*$
private String countType; *doK$wYP
int countId; V?v,q'? $
/** Creates a new instance of CountData */ sn&y;Vc[$
public CountBean() {} g]R }w@nJ
public void setCountType(String countTypes){ a3
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this.countType=countTypes; o~,dkV
} sB
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public void setCountId(int countIds){ kC"<4U
this.countId=countIds; Uu{I4ls6B
} D0tmNV@
public String getCountType(){ ;BqYhi
return countType; "jzU`
} !CROc}
public int getCountId(){ 7=t4;8|j;
return countId; rl9YB %P
} DPJ#Y -0
} M"2Tuwz
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CountCache.java L,| 60*
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/* }s=D,_}m
* CountCache.java Jz
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* zR(}X8fP
* Created on 2007年1月1日, 下午5:01 dJM)~Ay-
* $*^Ms>Pa_
* To change this template, choose Tools | Options and locate the template under 4df)?/
* the Source Creation and Management node. Right-click the template and choose M ()&GlNs
* Open. You can then make changes to the template in the Source Editor. 4[|^78
*/ ^4_)a0Kcm,
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package com.tot.count; y^tuybpZY<
import java.util.*; ulV)X/]1
/** twU^ewO&
* F6R+E;"4R'
* @author y|U3
*/ W/9dT^1y4'
public class CountCache { Ro$'|}(+A
public static LinkedList list=new LinkedList(); e.jrX;;$!&
/** Creates a new instance of CountCache */ z9pv|
public CountCache() {} :zZK%}G<
public static void add(CountBean cb){ " m<]B
if(cb!=null){ "S.5_@?
list.add(cb); 2Jl6Xc8
} Ehu^_HZ
} }z1aKa9
} jIwz
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CountControl.java AJt*48H*G
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/* #L5H-6nz
* CountThread.java L\}o(P(
* St9W{
* Created on 2007年1月1日, 下午4:57 M eo(|U
* dO}6zQ\
* To change this template, choose Tools | Options and locate the template under M_*"g>Z
* the Source Creation and Management node. Right-click the template and choose +<7~yZ[Z8
* Open. You can then make changes to the template in the Source Editor. p/L|;c
*/ )isz
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package com.tot.count; -/rP0h5#
import tot.db.DBUtils; =B@+[b0Z
import java.sql.*; o^FlQy\
/** lJ;7sgQ#
* WG>Nm89
* @author TeaP\a
*/ m/uBM6SXx
public class CountControl{ |`[0U
private static long lastExecuteTime=0;//上次更新时间 PNY"Lqj
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 3*x_S"h
/** Creates a new instance of CountThread */ !qk+>6~A,
public CountControl() {} H<41H;m
public synchronized void executeUpdate(){ jWk1FQte
Connection conn=null; wb~BY
PreparedStatement ps=null; N\{Xhr7d
try{ 4H'\nsM
conn = DBUtils.getConnection(); ci*rem
conn.setAutoCommit(false); xa#;<8 iV
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); ?D?_D,"C
for(int i=0;i<CountCache.list.size();i++){ hB/4.K ]8
CountBean cb=(CountBean)CountCache.list.getFirst(); 8AL`<8$
CountCache.list.removeFirst(); -P#PyZEH&I
ps.setInt(1, cb.getCountId()); & -L$B
ps.executeUpdate();⑴ Ug(;\*yg
//ps.addBatch();⑵ :Z)a&A9v
} %gUf
//int [] counts = ps.executeBatch();⑶ RlW0U-%u
conn.commit(); ?5'E P|<
}catch(Exception e){ 8Ld{Xg
e.printStackTrace(); Bv-|#sdxm
} finally{ &%eWCe++
try{ ZcJa:
if(ps!=null) { [ye!3h&]
ps.clearParameters(); [0vgA#6I
ps.close(); 2tPW1"M.n
ps=null; ; '6`hZ
} M~'4>h}
}catch(SQLException e){} u}_,4J
DBUtils.closeConnection(conn); _yx~t
} 4mHR+SZy
} <46>v<
public long getLast(){ 0PdeK'7
return lastExecuteTime; WXq=FZ-
} _{Z!$q6,
public void run(){ ?XCFRt,ol
long now = System.currentTimeMillis(); ki|KtKAu_9
if ((now - lastExecuteTime) > executeSep) { jGm`Qg{<
//System.out.print("lastExecuteTime:"+lastExecuteTime); 4)Jtc2z7Z\
//System.out.print(" now:"+now+"\n"); )ZZjuFQJ)
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); oVZI([O
lastExecuteTime=now; 8M6
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executeUpdate(); /;5U-<qf
} '%Fg+cZN\
else{ 4Fu:ov
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//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); ~,YxUn8@
} l<3X:)
} TEJn;D<1I,
} 8U8%XI EJ
//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 O$eNG$7
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类写好了,下面是在JSP中如下调用。 90"&KDh
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<% 8'sT zB]
CountBean cb=new CountBean(); lIhP\:;S&
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); xdLMy#U2
CountCache.add(cb); c/6
out.print(CountCache.list.size()+"<br>"); 9-/u _$
CountControl c=new CountControl(); }yzCq+
c.run(); 9ZJn 8ki
out.print(CountCache.list.size()+"<br>"); iY,FfuE
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