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: SyI#Q[f'_
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CountBean.java N]3XDd|q
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/* 2]|+.9B
* CountData.java +u7mw<A
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* c(:GsoO
* Created on 2007年1月1日, 下午4:44 rRxqV?>n!
* se&:Y&vrc~
* To change this template, choose Tools | Options and locate the template under wml`3$"cf
* the Source Creation and Management node. Right-click the template and choose HQ"D>hsuU
* Open. You can then make changes to the template in the Source Editor. tq{
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*/ uTQ/_$
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package com.tot.count; vq|W&
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/** krgsmDi7
* /p~gm\5Z
* @author xRb-m$B}L
*/ WlU5`NJl]2
public class CountBean { Xr-eDUEi
private String countType; M*nfWQ
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int countId; koFY7;_<?
/** Creates a new instance of CountData */ ,`K'qms
public CountBean() {} QM
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public void setCountType(String countTypes){ M^a QH/=:"
this.countType=countTypes; o@}Jd0D4
} [E+#+-n7
public void setCountId(int countIds){ 7^=O^!sa
this.countId=countIds; m3 ,i{
} ))<3+^S0V\
public String getCountType(){ ~)ls.NXI
return countType; ~u3E+w
} /_v@YB!0
public int getCountId(){ .7"
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return countId; SBs_rhe
} WI' ;e4
} |nIm$ p'
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CountCache.java G}d@^9FkE
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/* s-[ _%
* CountCache.java k1W
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* 6s@'z<Ct
* Created on 2007年1月1日, 下午5:01 w`q):yXX
* *s}dtJ
* To change this template, choose Tools | Options and locate the template under "*a^_tsT?i
* the Source Creation and Management node. Right-click the template and choose 6Dwj^e0
* Open. You can then make changes to the template in the Source Editor. ;vnG
*/ > -OQk"o
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package com.tot.count; s0WI93+z
import java.util.*; q3n(Z
/** jw]~g+x#$
* EA8K*>'pv
* @author 8wMu^3r
*/ 0P_qtS
public class CountCache { 8K=sx@l
public static LinkedList list=new LinkedList(); }j;*7x8(
/** Creates a new instance of CountCache */ .IXkdy
public CountCache() {} .-Yhpw>f
public static void add(CountBean cb){ BxVo>r
if(cb!=null){ NBU[> P
list.add(cb); \4zb9CxOZ
} Zl^#U c"
} ;Sl]8IZ
} R9%Um6
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CountControl.java 6qp2C]9=
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/* 1w*DU9f
* CountThread.java u2}zRC=
* 8&+m5xS
* Created on 2007年1月1日, 下午4:57 m_
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* ~?`V$G=?,
* To change this template, choose Tools | Options and locate the template under tn>z%6;&Z
* the Source Creation and Management node. Right-click the template and choose d)d\h`=Z
* Open. You can then make changes to the template in the Source Editor. ( CDwl,
*/ FyY<Vx'yQ
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package com.tot.count; ) bRj'*
import tot.db.DBUtils; w% Vw*i6o
import java.sql.*; 0@ccXFE
/** ':Avh|q3N
* Y;n;7M<F
* @author fdk]i/*)
*/ 1VRexp
public class CountControl{ *?dw`j_b >
private static long lastExecuteTime=0;//上次更新时间 ! 3&_#VO
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 uv>T8(w
/** Creates a new instance of CountThread */ 0{0BL@H
public CountControl() {} V)Oj6nD]
public synchronized void executeUpdate(){ E6
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Connection conn=null; tw{V7r~n
PreparedStatement ps=null; x|3f$
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try{ {tqLH2cO
conn = DBUtils.getConnection(); n\CQ-*;l
conn.setAutoCommit(false); [,_4#Zz
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); g3*" ^C2=
for(int i=0;i<CountCache.list.size();i++){ <S/`-/=2
CountBean cb=(CountBean)CountCache.list.getFirst(); {-FS+D`
CountCache.list.removeFirst(); ;}/@ar7s3
ps.setInt(1, cb.getCountId()); k#*tf:R
ps.executeUpdate();⑴ cU`sA_f
//ps.addBatch();⑵ WcE{1&PXx
} gt~hUwL
//int [] counts = ps.executeBatch();⑶ HZ>8@AVa\
conn.commit(); %(72+B70R
}catch(Exception e){ 8+gti*C?\
e.printStackTrace(); dM|&Y6
} finally{ F%<hng%k
try{ P8Nzz(JF
if(ps!=null) { aDXdr\C6
ps.clearParameters(); _4H}OGZI
ps.close(); Ujw J}j
ps=null; ^7cZ9/3
} C9?R*2L>
}catch(SQLException e){} =SY5E{`4p
DBUtils.closeConnection(conn); Q2 tM~
} X[F<sxw
} <M//zXa
public long getLast(){ 2d%j6D
return lastExecuteTime; H\BhAf
} Q"2t:
public void run(){ _'g'M=E
long now = System.currentTimeMillis(); [#}A]1N
if ((now - lastExecuteTime) > executeSep) { a-P'h1hbH
//System.out.print("lastExecuteTime:"+lastExecuteTime); 3M/iuu
//System.out.print(" now:"+now+"\n"); ~hJ/&,vH!
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); S}0W<H P
lastExecuteTime=now; ubq4Zv7'
executeUpdate(); CTqAhL 4}
} Mo4#UV
else{ p^=>N9
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); 8|\0\Wd;vu
} :j sa.X
} caK<;bmu-
} s|/m}n
//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 vY+{zGF
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类写好了,下面是在JSP中如下调用。 Afpj*o
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<% &) '5_#S
CountBean cb=new CountBean(); (WW*yv.J
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); {i:5XL
CountCache.add(cb); %SWtE5HZQq
out.print(CountCache.list.size()+"<br>"); KJ7[DN'(
CountControl c=new CountControl(); 1x\Vz\
c.run(); lnXb]tm;
out.print(CountCache.list.size()+"<br>"); !11x&Db
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