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: p1BMQ?=($
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CountBean.java vk1E!T9X
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/* s^&Oh*SP*
* CountData.java `F(ghC
* ;q"Yz-3
* Created on 2007年1月1日, 下午4:44 Tr6J+hS
* $>M-oNeC
* To change this template, choose Tools | Options and locate the template under R(^2+mV?
* the Source Creation and Management node. Right-click the template and choose 1(YEOZ
* Open. You can then make changes to the template in the Source Editor. M+|J;caX
*/ &s{" Vc9]
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package com.tot.count; Lu][0+-
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/** %U
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* \@8.BCWK
* @author 5R%4fzr&g
*/ Iq?#kV9)
public class CountBean { ):L ; P)
private String countType; ]?<=DHn
int countId; Ovhd%qV;Y
/** Creates a new instance of CountData */ T?4I\SG
public CountBean() {} l ~C=yP(~
public void setCountType(String countTypes){ ~u.((GM
this.countType=countTypes; `zP{E T_Y
} lP;X=X>
public void setCountId(int countIds){ tb1w 6jaU
this.countId=countIds; 'V`Hp$r
} bd;?oYV~
public String getCountType(){ n85d
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return countType; +oRBSAg -
} GF/!@N
public int getCountId(){ X4$86
return countId; \2^_v'
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} ~gi,ky^!
} 0Q{^BgW
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CountCache.java t,IQ|B&0
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/* K9=f`JI9
* CountCache.java $v\o14v
* VSDG_:!K
* Created on 2007年1月1日, 下午5:01 '\wZKYVN
* rk)h_zN
* To change this template, choose Tools | Options and locate the template under nl/~7({
* the Source Creation and Management node. Right-click the template and choose ;56mkP
* Open. You can then make changes to the template in the Source Editor. v2KK%Qy
*/ 1$RUhxT
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package com.tot.count; TD^w|U.
import java.util.*; P/Zp3O H
/** P+gYLX8
* )2&y;{]
* @author >mCS`D8
*/ f}ES8Hh[
public class CountCache { 5-B % 08T
public static LinkedList list=new LinkedList(); @w
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/** Creates a new instance of CountCache */ )Q5ja}-{V
public CountCache() {} zi?G
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public static void add(CountBean cb){ ^b&U0k$R
if(cb!=null){ E,gpi
list.add(cb); _J ZlXY
} 9
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} !McRtxq?~
} +2Wijrn
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CountControl.java @mm~i~~KA
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/* R.)w
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* CountThread.java e;r?g67
* ~0T,_N
* Created on 2007年1月1日, 下午4:57 X{-901J1
* cIB[D.
* To change this template, choose Tools | Options and locate the template under p`T,VU&.
* the Source Creation and Management node. Right-click the template and choose gK",D^6T*Y
* Open. You can then make changes to the template in the Source Editor. N}X7g0>hV
*/ 6$x9@x8
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package com.tot.count; T@gm0igW/;
import tot.db.DBUtils; t(r}jU=qw
import java.sql.*; 5"^Z7+6
/** Xb\de_8!
* "[Hn G(gA
* @author dW} m44X
*/ <}n"gk1is
public class CountControl{ ]v|n'D-?
private static long lastExecuteTime=0;//上次更新时间 BU=;rz!;
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 ^7-l<R[T
/** Creates a new instance of CountThread */ S0jYk (
public CountControl() {} BaXf=RsZ
public synchronized void executeUpdate(){ 6sz:rv}
Connection conn=null; Y9ipy_@_?
PreparedStatement ps=null; L`n Ma
try{ | \6Ff/O
conn = DBUtils.getConnection(); mm9xO%
conn.setAutoCommit(false); ;)ji3 M
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); a@s@E
for(int i=0;i<CountCache.list.size();i++){ ||o :A
CountBean cb=(CountBean)CountCache.list.getFirst(); SioP`*,}
CountCache.list.removeFirst(); "fZWAGDBO\
ps.setInt(1, cb.getCountId()); >8=rD
ps.executeUpdate();⑴ :~4M9
//ps.addBatch();⑵ *di}rQHm
} 2Wp)CI<\D
//int [] counts = ps.executeBatch();⑶ \Rz-*zr&
conn.commit(); ql2O%B.6?
}catch(Exception e){ 2YhtD A
e.printStackTrace(); GPLq$^AH
} finally{ 0.lOSAq
try{ )9s
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if(ps!=null) { iZn<j'u
ps.clearParameters(); f,0,:)
ps.close(); / &#b*46
ps=null; N)Qz:o0W
} s8|Fe_
}catch(SQLException e){} 2{I+H'w8:
DBUtils.closeConnection(conn); =L9;8THY
} {1m.d;(1
} 09sdt;V Q
public long getLast(){ xXfFi5Eom
return lastExecuteTime; ~?<VT
k
} U8GvUysB!
public void run(){ gSt'<v
long now = System.currentTimeMillis(); B0$.oavC
if ((now - lastExecuteTime) > executeSep) { [&K"OQ^\2h
//System.out.print("lastExecuteTime:"+lastExecuteTime); a
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//System.out.print(" now:"+now+"\n"); J8#3?Lp
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); Dx>~^ ^<
lastExecuteTime=now; [$FiXH J
executeUpdate(); A`ScAzx5{
} LypBS]ru
else{ ,@r 0-gL
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); yYn7y1B
} 9KDm<Q-mf
} l$J2|\M6
} {<L|Z=&k`
//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 66Bx,]"6
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类写好了,下面是在JSP中如下调用。 @@} ]qT*
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<% GRj#1OqL
CountBean cb=new CountBean(); B
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cb.setCountId(Integer.parseInt(request.getParameter("cid"))); jV~+=(w)
CountCache.add(cb); Pe)SugCs
out.print(CountCache.list.size()+"<br>"); C[Nh>V7=
CountControl c=new CountControl(); =v49[i
c.run(); ~xU\%@I\
out.print(CountCache.list.size()+"<br>"); B> V)6\
%>