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: /pIb@:Y1?
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CountBean.java 0qL
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/* '/u:,ar
* CountData.java `gt&Y-
* or%gTVZ
* Created on 2007年1月1日, 下午4:44 >1a\%G
* @W1WReK]f
* To change this template, choose Tools | Options and locate the template under tFvgvx\:
* the Source Creation and Management node. Right-click the template and choose }}``~
* Open. You can then make changes to the template in the Source Editor. PJK]t7vp
*/ fY%M=,t3c
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package com.tot.count; Q k;Kn
*qO]v9 j
/** i{|lsd(+
* %uz|NRB=
* @author YV1a3
*/ X"TUe>cM
public class CountBean { cVB|sYdf
private String countType; k_K,J6_)
int countId; e+F}9HR7
/** Creates a new instance of CountData */ j(Fa=pi
public CountBean() {} /zl3&~4
public void setCountType(String countTypes){ OAW=Pozr9
this.countType=countTypes; rb *C-NutE
} A#Q0{z@H
public void setCountId(int countIds){ --
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this.countId=countIds; ;# R3k
} Ws^+7u
public String getCountType(){ YeRcf`
return countType; q,;".3VQ
} Z]x5!
public int getCountId(){ 6K4`;
return countId; w69>tC
} &*(n<5wt
} q)K-vt)98
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CountCache.java Ynv9&P
0)A=+zSS1
/* Yl)eh(\&J
* CountCache.java &5kZ{,-eM
* pG,<_N@P
* Created on 2007年1月1日, 下午5:01 tk`: CT
*
* eZ@Gu
* To change this template, choose Tools | Options and locate the template under 51o@b
* the Source Creation and Management node. Right-click the template and choose I;Al?&uw
* Open. You can then make changes to the template in the Source Editor. f![xn2T
*/ /{fZH,!L
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package com.tot.count; `j"4:
import java.util.*; /;(<fh<bY
/** {[Uti^)m%
* -/M9 vS
* @author }7iUagN
*/ nnfY$&3A
public class CountCache { 2yl6~(JC+
public static LinkedList list=new LinkedList(); eZynF<i
/** Creates a new instance of CountCache */ !(B_EM
public CountCache() {} D",A$(lG
public static void add(CountBean cb){ hX0RET
if(cb!=null){ NOF?LV
list.add(cb); D4AEZgC F,
} 3 sS=?q
} jz
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} !$D&6M|C8l
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CountControl.java NV:>a
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/* t G]N*%@
* CountThread.java .H
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* D._{E*vg
* Created on 2007年1月1日, 下午4:57 l<$rqz3D
* Po!oN~r
* To change this template, choose Tools | Options and locate the template under +:}kZDl@ X
* the Source Creation and Management node. Right-click the template and choose NI^{$QMj
* Open. You can then make changes to the template in the Source Editor. -y%QRO(
*/ 1JIG+ZN md
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package com.tot.count; 8098y,mQe
import tot.db.DBUtils; 4/b(Y4$,[r
import java.sql.*; QQ*gFP.Ao
/** x,w8r+~5
* gRHtgR)T3
* @author WmNA5;<Q
*/ Umij!=GPG^
public class CountControl{ D2{L=
private static long lastExecuteTime=0;//上次更新时间 ^,LtEwd~Y
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 X|,["Az
8
/** Creates a new instance of CountThread */ +.=1^+a
public CountControl() {} OH>r[,z0
public synchronized void executeUpdate(){ ;r3}g"D@
Connection conn=null; lbd(j{h>4
PreparedStatement ps=null; {yTpRQN~
try{ [8.-(-/;
conn = DBUtils.getConnection(); 7aV$YuL)X~
conn.setAutoCommit(false); f`,-b
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); axtb<5&
for(int i=0;i<CountCache.list.size();i++){ '(tj[&aL
CountBean cb=(CountBean)CountCache.list.getFirst(); (nq^\ZdF
CountCache.list.removeFirst(); alVdQfu
ps.setInt(1, cb.getCountId()); ![
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ps.executeUpdate();⑴ RJ@\W=aZ
//ps.addBatch();⑵ Q<1L`_.>
} BGN9,ii
//int [] counts = ps.executeBatch();⑶ X{`1:c'x
conn.commit(); se#@)LtZ
}catch(Exception e){ RtwUb(wn6
e.printStackTrace(); "-P/jk
} finally{ 9)Ly}Kzx
try{ /9Z!p
if(ps!=null) { Jr]gEBX
ps.clearParameters(); "H$@b`)
ps.close(); hXc}r6<B
ps=null; Q(e{~
]*
} C B/r]+4
}catch(SQLException e){} V9Hl1\j^
DBUtils.closeConnection(conn); IT18v[-G
} *7Xzht&f
} !VRo*[yD@
public long getLast(){ Y&5.9 s@'
return lastExecuteTime; Mb.4J2F ?
} T
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public void run(){ '60//"9>k/
long now = System.currentTimeMillis(); :3O5ET'1
if ((now - lastExecuteTime) > executeSep) { G|*G9nQ
//System.out.print("lastExecuteTime:"+lastExecuteTime); CdL.?^
//System.out.print(" now:"+now+"\n"); @Z q[e
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); j8a[
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lastExecuteTime=now; E30Z`$cz:
executeUpdate(); r^5jh1
} P#;Th8k{K2
else{ AG>\aV"b
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); ?
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} !}t-j3bCs
} RX>2~^
} vBoO'l9'M
//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 `ET& VV
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类写好了,下面是在JSP中如下调用。 ,v7Q *3
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<% p[qg&VKB
CountBean cb=new CountBean(); 4K7{f+T
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); QC7k~I8
CountCache.add(cb); nNQ-"t
out.print(CountCache.list.size()+"<br>"); oY.\)eJ~>
CountControl c=new CountControl(); q3+8]-9|5
c.run(); %*K;np-q{
out.print(CountCache.list.size()+"<br>"); K<RqBecB
%>