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: zI~owK)%Z
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CountBean.java `OymAyEYQ
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/* 8q`$y$06Dk
* CountData.java ^-FRTC
* |[9?ma
* Created on 2007年1月1日, 下午4:44 CF|]e:
* GE|+fYVM-$
* To change this template, choose Tools | Options and locate the template under Rl|4S[
* the Source Creation and Management node. Right-click the template and choose TpA\9N#$
* Open. You can then make changes to the template in the Source Editor. azjEq$<M
*/ y2O4I'/5<
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package com.tot.count; 2xw6 5z
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/** fF*`'i=!
* j@Qg0F
* @author &R~n>>c
*/ EBtLzbj
public class CountBean { G8W#<1LE
private String countType; RtG}h[k/X
int countId; "U.^lkN
/** Creates a new instance of CountData */ `IYuz:
public CountBean() {} p0.|<
public void setCountType(String countTypes){ M4ozTp<$O
this.countType=countTypes; K/ &?VIi`z
} ND<!4!R^
public void setCountId(int countIds){ 8@NH%zWBp
this.countId=countIds; :Q+5,v-c
} I ];M7
public String getCountType(){ ylKmj]A
return countType; 9+,R`v
} t6c<kIQ:-O
public int getCountId(){ "^I
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return countId; Nr2 C@FU:0
} RFh"&0[
} E{HY!L[
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CountCache.java 5unG#szq
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/* M8k"je7`s
* CountCache.java 7?OH,^
* `RMI(zI3g.
* Created on 2007年1月1日, 下午5:01 DoC(Z)o
* */ G<!W
* To change this template, choose Tools | Options and locate the template under sBv>E}*R
* the Source Creation and Management node. Right-click the template and choose 4`#F^2r!
* Open. You can then make changes to the template in the Source Editor. ?)'~~@NkH
*/ 39{{7(hh
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package com.tot.count; k7tYa;C
import java.util.*; .^)UO
/** s08u @
* rzp +:
* @author ,mPnQ?
*/ Oo?,fw
public class CountCache { 4E44Hzs
public static LinkedList list=new LinkedList(); Y+/JsOD
/** Creates a new instance of CountCache */ D .vw8H3
public CountCache() {} E2GGEKrW
public static void add(CountBean cb){ K!D
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if(cb!=null){ yV)m"j
list.add(cb); K; FW
} 0oy-os
} jClj_E
} ]0D}T'wM
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CountControl.java ch5s<x#CE
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/* K}[>T(0E
* CountThread.java ck#"*],
* ,?
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* Created on 2007年1月1日, 下午4:57 9>/wUQs!]
* HG/p$L*
* To change this template, choose Tools | Options and locate the template under =TR,~8Z|
* the Source Creation and Management node. Right-click the template and choose Gf8s?l
* Open. You can then make changes to the template in the Source Editor. -{h
*/
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package com.tot.count; 3CTX -#)vS
import tot.db.DBUtils;
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import java.sql.*; bIt=v)%$
/** r!}al5~&
* Dc~,D1xWj
* @author H* !EP
*/ %/kyT%1
public class CountControl{ G;gJNK"e
private static long lastExecuteTime=0;//上次更新时间 ^"8G`B$r
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 T~sTBGcv
/** Creates a new instance of CountThread */ {#IPf0O
public CountControl() {} CeT~p6=
public synchronized void executeUpdate(){ 4t4olkK3Oa
Connection conn=null; C@o%J.9"#
PreparedStatement ps=null; 6]Q3Yz^h
try{ lC97_T
conn = DBUtils.getConnection(); dAJ,x
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conn.setAutoCommit(false); '+<(;2Z
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ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); nW\(IkX\
for(int i=0;i<CountCache.list.size();i++){ ;%J5=f%z)
CountBean cb=(CountBean)CountCache.list.getFirst(); 89o)M5KQ
CountCache.list.removeFirst(); 'NZGQebK
ps.setInt(1, cb.getCountId()); 4X
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ps.executeUpdate();⑴ b(GFMk
//ps.addBatch();⑵ ,]R8(bD)
} 3E} An%
//int [] counts = ps.executeBatch();⑶ eT"Uxhs-}
conn.commit(); O`FqD{@V
}catch(Exception e){ OH<?DcfeL
e.printStackTrace(); T0j2a&Pv
} finally{ 3L-^<'~-k;
try{ jW*1E*"
if(ps!=null) { :ZdUx
ps.clearParameters(); ~Pk0u{,4XQ
ps.close(); %R_{1GrL'c
ps=null; ?_6YtR,{
} =fc:6JR
}catch(SQLException e){} ,KW;2t*IQ@
DBUtils.closeConnection(conn); Hv#q:R8
} l QPqcZd
} ? y},,
public long getLast(){ (k-YI{D3
return lastExecuteTime; uK*Nu^
} Bp AB5=M0
public void run(){ @-.? B
long now = System.currentTimeMillis(); Z\X'd_1!
if ((now - lastExecuteTime) > executeSep) { x_@i(oQ:_
//System.out.print("lastExecuteTime:"+lastExecuteTime); y_F}s9wj
//System.out.print(" now:"+now+"\n"); }{7e7tW6
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); ~QG?k
lastExecuteTime=now; p5c8YfM
executeUpdate(); ~pP0|B*%
} pLoy
else{ "5DJu~
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); V7CoZnz
} DrS~lTf=>
} ?s}
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} t> Q{yw
//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 ?`sy%G
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类写好了,下面是在JSP中如下调用。 P1 +"v*
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<% 90 {tI X
CountBean cb=new CountBean(); 7u11&(Lz
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); 7-iIay1h"
CountCache.add(cb); lhn8^hOJ/
out.print(CountCache.list.size()+"<br>"); :,]S}R
CountControl c=new CountControl(); ,-*iCs<
c.run(); jy$@a%FD
out.print(CountCache.list.size()+"<br>"); X\GM/A
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