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: a~jU~('4}w
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CountBean.java .&fG_(6|
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/* ;zk& 7P0
* CountData.java [vCZoG8+>
* k'Is]=3
* Created on 2007年1月1日, 下午4:44 Q'D%?Vg'
* 6jz6
* To change this template, choose Tools | Options and locate the template under xe9E</M_
* the Source Creation and Management node. Right-click the template and choose SbS*z:
* Open. You can then make changes to the template in the Source Editor. VrDSN
*/ ~.\CG'g
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package com.tot.count; tP/0_^m
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/** *l\wl @{
* OI:G~Wg
* @author ?Vg251-H
*/ N 0<([B;
public class CountBean { &5k$v^W5
private String countType; HoE@t-S
int countId; tbMf_-g
/** Creates a new instance of CountData */ U4`6S43ki
public CountBean() {} zl8O @g
public void setCountType(String countTypes){ lsJl+%&8
this.countType=countTypes; V?pqKQL0
} vKrOIBP
public void setCountId(int countIds){ K[{hh;7
this.countId=countIds; dQW=k^X 'U
} |qe[`x;
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public String getCountType(){ G':wJ7[]`
return countType; lRb|GS.h/
} y~eQVnH5W
public int getCountId(){ &!Sq6<!v2
return countId; W&MZ5t,k=
} J)7m::%I
} rLP:kP'b
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CountCache.java Ss>ez8q
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/* vlW521
* CountCache.java rf@Cz%xDD
* )T2V<3l
* Created on 2007年1月1日, 下午5:01 w4I&SLm-b
* bxU 2.YC
* To change this template, choose Tools | Options and locate the template under e3T&KyPm?+
* the Source Creation and Management node. Right-click the template and choose 5D9n>K4|
* Open. You can then make changes to the template in the Source Editor. yE+Wb[H[
*/ `4GEq2%
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package com.tot.count; lQ5d.}O&
import java.util.*; o;w5;TkY
/** !Q/oj
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* U1oZ\Mh
* @author )I&,kH)+
*/ ,hO*W-a%1
public class CountCache { ;iB9\p$K)
public static LinkedList list=new LinkedList(); [2~^~K
/** Creates a new instance of CountCache */ d `eX_] Z
public CountCache() {} b({K6#?'[
public static void add(CountBean cb){ ,oin<K
if(cb!=null){ :`jB1rI
list.add(cb); z?Hi
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} /2s=;tA1
} +)J;4B
}
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CountControl.java nr*nX
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/* 3haR/YN
* CountThread.java )~>
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* d2~*fHx_!
* Created on 2007年1月1日, 下午4:57 %?sPKOh3N}
* q7#4e?1
* To change this template, choose Tools | Options and locate the template under :}B=Bk/q
* the Source Creation and Management node. Right-click the template and choose +mu.W
r
* Open. You can then make changes to the template in the Source Editor. ?:$aX@r
*/ r(qwzUI
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package com.tot.count; 4LY$;J;2
import tot.db.DBUtils; OTy{:ID
import java.sql.*; ":I@>t{H*
/** R(t1Ei.-?
* $c1zMkY)u
* @author 2%{(BT6
*/ 2h;#BJ))
public class CountControl{ a62'\wF>D
private static long lastExecuteTime=0;//上次更新时间 #TUuk
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 kq$0~lNI$
/** Creates a new instance of CountThread */ )/:j$aq
public CountControl() {} l b9O
public synchronized void executeUpdate(){ > r
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Connection conn=null; ._X|Ye9/
PreparedStatement ps=null; :q>uj5%
try{ p~A6:"8s`=
conn = DBUtils.getConnection(); 5+Ld1nom
conn.setAutoCommit(false); 7QXp\<7
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); Jx+e_k$gHO
for(int i=0;i<CountCache.list.size();i++){ [<nmJ-V
CountBean cb=(CountBean)CountCache.list.getFirst(); <(E9U.
CountCache.list.removeFirst(); 6Cpn::WW}
ps.setInt(1, cb.getCountId()); 8V?*Bz-4`
ps.executeUpdate();⑴ }VU7wMk
//ps.addBatch();⑵ Can:!48
} oF(=@UL
//int [] counts = ps.executeBatch();⑶ j6&q6C X
conn.commit(); #TG7WF5
}catch(Exception e){ xoB "hNIX
e.printStackTrace(); w3>.d(Q
} finally{ O>c2*9PM
try{ SB)Hz8<
if(ps!=null) { N5F+h94z]
ps.clearParameters(); A+QOox]<
ps.close(); Io*mFa?
ps=null; ~a ]R7X7
} 1nZ7xCDK98
}catch(SQLException e){} Fs_zNN
DBUtils.closeConnection(conn); Ly~s84k_po
} cT.8&EEW
} )e?6 Ncy
public long getLast(){ 6j6P&[
return lastExecuteTime; X[E!q$ag
} m\"X%Y#
public void run(){ na`8ulN_
long now = System.currentTimeMillis(); 4_KRH1
if ((now - lastExecuteTime) > executeSep) { FdE9k\E#/)
//System.out.print("lastExecuteTime:"+lastExecuteTime); G0mvrc-(
//System.out.print(" now:"+now+"\n"); lxh}N,
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); D>6vI
lastExecuteTime=now; *7`amF-
executeUpdate(); "t>WM
} rx\f:-3g
else{ $=ua$R4Z+
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); VthM`~3
} =rzhaU'A'
} >U#j\2!Sg
} +9NI=s6
//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 _s~F/G`iT
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类写好了,下面是在JSP中如下调用。 dz"HO!9
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<% T,uVt^.R+
CountBean cb=new CountBean(); IuOQX}
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); FV>xAU$
CountCache.add(cb); IWNIk9T,u
out.print(CountCache.list.size()+"<br>"); V5up/ 6b,1
CountControl c=new CountControl(); 3BK_$Fy
c.run(); g7`uWAxZa
out.print(CountCache.list.size()+"<br>"); lfe^_`ij(+
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