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: cOmw?kA*G
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CountBean.java JU1~e@/'%
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/* e2 4WW^S
* CountData.java o[Q MT P
* (y=C_wvqZ
* Created on 2007年1月1日, 下午4:44 %
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* {f/~1G[M
* To change this template, choose Tools | Options and locate the template under k9sh @ENy
* the Source Creation and Management node. Right-click the template and choose vYwYQG
* Open. You can then make changes to the template in the Source Editor. $v4.sl:x
*/ ysQ_[
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package com.tot.count; #^u$
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/** W#9BNKL
* tU }h~&M
* @author U dT*E: 6
*/ uw>Ba %5
public class CountBean { g1/:Q%R,
private String countType; pnl{&<$C%C
int countId; jwc)Lj}
/** Creates a new instance of CountData */ k^3>Y%^1
public CountBean() {} EU2$f
public void setCountType(String countTypes){ |7'df &CA
this.countType=countTypes; *v;2PP[^
} CM/H9Kz.
public void setCountId(int countIds){ ? &o2st
this.countId=countIds; N({MPO9
} [owWiN4`s
public String getCountType(){ Jj; L3S
return countType; \j@OZ
} 1!xQ=DU"
public int getCountId(){ ,Xu-@br{
return countId; xgwY@'GN
} l5S aT,%
} )Kc<j!8-[
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CountCache.java %f&/E"M
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/* ,;EIh}
* CountCache.java D$w6V
* v,FU^f-'
* Created on 2007年1月1日, 下午5:01 3+)J
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* 3]5^r}
* To change this template, choose Tools | Options and locate the template under Z)I+@2
* the Source Creation and Management node. Right-click the template and choose 29;?I3<
*
* Open. You can then make changes to the template in the Source Editor. ^h(ew1:
*/ t|w_i-&b,
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package com.tot.count; hE-h`'ha`
import java.util.*; @x*c1%wg
/** +%+tr*04O
* KoOz#,()
* @author rMdt:`
*/ ?h$NAL?
public class CountCache { u0JB\)(-/h
public static LinkedList list=new LinkedList(); UFXaEl}R
/** Creates a new instance of CountCache */ QmQ=q7
public CountCache() {} %6|nb:Oa
public static void add(CountBean cb){ 5MroNr
if(cb!=null){ H`*LBqDk
list.add(cb); EEEh~6?-e
} M1k{t%M+S
} 9&$y}Y
}
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CountControl.java 0eT(J7[ <
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/* UE8kpa)cQ
* CountThread.java vDp8__^
* G"r1+#
* Created on 2007年1月1日, 下午4:57 W,K;6TZhh
* JgxtlYjl
* To change this template, choose Tools | Options and locate the template under \Z?9{J
* the Source Creation and Management node. Right-click the template and choose R|6Cv3:
* Open. You can then make changes to the template in the Source Editor. bZ dNibN
*/ @3>u@
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package com.tot.count; TJ2=m9Z
import tot.db.DBUtils; {0[tNth'h
import java.sql.*; y%&q/tk
/** S8kCp;
* 'F/~o1\.
* @author 5VfyU8)7X
*/ {0L1X6eg
public class CountControl{ `xKp%9
private static long lastExecuteTime=0;//上次更新时间 ^%d\qd`
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 YX!{P=Ua
/** Creates a new instance of CountThread */ zykT*V
public CountControl() {} hwPw]Ln/
public synchronized void executeUpdate(){ ~Q Oe##
Connection conn=null; F|IAiE
PreparedStatement ps=null; @D]5c ivm_
try{ ^ sOQi6pL
conn = DBUtils.getConnection(); X1DF*wI
conn.setAutoCommit(false); &xU[E!2H%
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?");
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for(int i=0;i<CountCache.list.size();i++){ cutu DZ
CountBean cb=(CountBean)CountCache.list.getFirst(); {AhthR%(1
CountCache.list.removeFirst(); U'k*_g
ps.setInt(1, cb.getCountId()); A`N,
ps.executeUpdate();⑴ TEP,Dq
//ps.addBatch();⑵ ;dkYf24
} T]^62(So
//int [] counts = ps.executeBatch();⑶ )%`c_FL@N=
conn.commit(); WltQ63u
}catch(Exception e){ xzdf^Ce
e.printStackTrace(); GF"hx`zyJ
} finally{ {dhXIs
try{ _:ReN_0
if(ps!=null) { z{8bvuE
ps.clearParameters(); KWq+PeB5TS
ps.close(); dph{74Dc
ps=null; '3R`lv
} $By<$
}catch(SQLException e){} 8^kGS-+^
DBUtils.closeConnection(conn); KKb,d0T[
} 46}g7skD
} .ODU
public long getLast(){ ]vz%iv_
return lastExecuteTime; vt/x
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} cb@?}(aFl
public void run(){ ](Xb_xMf
long now = System.currentTimeMillis(); %@<8<6&q
if ((now - lastExecuteTime) > executeSep) { fnpYT:%fG
//System.out.print("lastExecuteTime:"+lastExecuteTime); Y@NNrGDkT*
//System.out.print(" now:"+now+"\n"); `jDTzhO~
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); 5^}\4.eXo
lastExecuteTime=now; 9)D6Nm
executeUpdate(); SU MrFd~
} o5u3Fjz3
else{ |-b#9JQ[A
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); 4`lLf
} N&.H|5
} `:ArT}F
} $r^GE
//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 Fh)IgzFj
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类写好了,下面是在JSP中如下调用。 >>QY'1Eu
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<% @T@<_ ?)
CountBean cb=new CountBean(); v>6"j1Z
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); JOj;^h
CountCache.add(cb); 0B[="rTS7#
out.print(CountCache.list.size()+"<br>"); v|Pv 03%?7
CountControl c=new CountControl(); 9d>-MX'
c.run(); ]N/=Dd+|
out.print(CountCache.list.size()+"<br>"); -5)H<dAQZ
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