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: &wN
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CountBean.java Q7|13^|C
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/* 5F"?]'*/
* CountData.java A ? M]5d
* ~8*oGG~s
* Created on 2007年1月1日, 下午4:44 B5:g{,C
* F-^HN%
* To change this template, choose Tools | Options and locate the template under `VtwKt*
* the Source Creation and Management node. Right-click the template and choose <+gl"lG
* Open. You can then make changes to the template in the Source Editor. (fa?ftK
*/ s3{s.55{m
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package com.tot.count; 3Mx@
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/** !dY:S';~
* SbZt\a 8
* @author u4@e=vWI
*/ cA?
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public class CountBean { 2HXKz7da
private String countType; 9Yyg}l:
int countId; Nb~dw;t
/** Creates a new instance of CountData */ C8E C?fSQ
public CountBean() {} N;'HR)
public void setCountType(String countTypes){ N-`;\
this.countType=countTypes; hXm}d\
} ,dx)rZ*
public void setCountId(int countIds){ m>ycN
this.countId=countIds; "<x~{BN?
} lGUV(D
public String getCountType(){ u!o]Co>
return countType; NRisr
} B#"|5
public int getCountId(){ SDHc[66'
return countId; nKB&|!
} p{q!jm~Nq
} ]M;6o@hq
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CountCache.java .vS6_
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/* HhmVV"g
* CountCache.java PgLS\_B
* "F$o!Vk
* Created on 2007年1月1日, 下午5:01 [fi'=Cb
* ShJK&70O
* To change this template, choose Tools | Options and locate the template under cEc,eq|
* the Source Creation and Management node. Right-click the template and choose F,M"/hnPT
* Open. You can then make changes to the template in the Source Editor. XcMJD(!
*/ ,6;xr'[o*
}b+QYSt
package com.tot.count; 1/ pA/UVO
import java.util.*; _]xt65TL
/** RR!!hY3 K
* .3<IOtD=
* @author Jh4&Qh|t
*/ x$GsDV
public class CountCache { xDJ+BQ<1A
public static LinkedList list=new LinkedList(); `%M-7n9Y
/** Creates a new instance of CountCache */ W Gw!Y1wq
public CountCache() {} 2l@"p!ar=
public static void add(CountBean cb){ oD#>8Aw s
if(cb!=null){ kq~[k.
list.add(cb); R
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} ncattp
} /%YiZ#
} zLQ#GF
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CountControl.java z5`8G =A
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/* j;20JA/b
* CountThread.java "6N~2q,SW
* ,.jHV
* Created on 2007年1月1日, 下午4:57 s`=/fvf.
* ~r^5-\[hZ
* To change this template, choose Tools | Options and locate the template under LuP?$~z
* the Source Creation and Management node. Right-click the template and choose hiRR+`L%
* Open. You can then make changes to the template in the Source Editor. Y^6[[vaj2
*/ hyb +#R
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package com.tot.count; $iqi:vY
import tot.db.DBUtils; &.Latx
import java.sql.*; Ji6`-~ k
/** P$18Xno{
* :%#r.p"6x
* @author :vK(LU0K
*/ ^'&iYV
public class CountControl{ =r@gJw:B
private static long lastExecuteTime=0;//上次更新时间 a1G9wC:e
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 *i?rJH
/** Creates a new instance of CountThread */ |vfujzRZ
public CountControl() {} px_s@>l`
public synchronized void executeUpdate(){ ~J1;tZS
Connection conn=null; r|^lt7\
PreparedStatement ps=null; N(:nF5>_
try{ 4e@&QOo`Cu
conn = DBUtils.getConnection(); /e|[SITe
conn.setAutoCommit(false); 8Y\OCwO
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); Er"R;l]xJ
for(int i=0;i<CountCache.list.size();i++){ LgP> u?]n
CountBean cb=(CountBean)CountCache.list.getFirst(); %e
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CountCache.list.removeFirst(); y98JiNq
ps.setInt(1, cb.getCountId()); \ I^nx+l
ps.executeUpdate();⑴ W ""*hJ
//ps.addBatch();⑵ O[IR|
} 4r1<,{gCS
//int [] counts = ps.executeBatch();⑶ NTm<6Is`
conn.commit(); RQ^m6)BTo
}catch(Exception e){ PNbcy!\U
e.printStackTrace(); #9D/jYK1X
} finally{ *#lBQBH|.
try{ @%OPy|=,{
if(ps!=null) { mA(nyF
ps.clearParameters(); LAv:+o(m/
ps.close(); "Su
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ps=null; jVad)2D
} wfBuU>
}catch(SQLException e){} vZb|!#I
DBUtils.closeConnection(conn); -c+[6A>j
} ^n&]HzT`y
} s>jr1~~3O_
public long getLast(){ O`i)?BC
return lastExecuteTime; Y^R?Q'
} {gFAvMj#
public void run(){ GS
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long now = System.currentTimeMillis(); -uA 3Y
if ((now - lastExecuteTime) > executeSep) { }+Rgx@XZ\
//System.out.print("lastExecuteTime:"+lastExecuteTime); ,<@,gZru
//System.out.print(" now:"+now+"\n"); ]<27Sw&yaG
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); 17>5#JLP
lastExecuteTime=now; |} K
executeUpdate(); E?Zb~xk
} I %|@3=Yc
else{ %cH8;5U40
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); ,
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} ^I X%dzM
} n1QEu"~Zj
} `d7gm;ykp
//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 @B,j;2eb
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类写好了,下面是在JSP中如下调用。 .E+OmJwD
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<% u64@"P
CountBean cb=new CountBean(); #^|| ]g/N
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); |',M_
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CountCache.add(cb); m`hGDp3
out.print(CountCache.list.size()+"<br>"); -#LjI.
CountControl c=new CountControl(); CO-Iar
c.run(); /8xH$n&xoC
out.print(CountCache.list.size()+"<br>"); fL!V$]HNt
%>