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: 9}jq`xSL
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CountBean.java m_Ac/ctf
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/* O][Nl^dl
* CountData.java i$^B-
* Xz.Y-5)
* Created on 2007年1月1日, 下午4:44 "3i80R\w`F
* _X2EBpZp
* To change this template, choose Tools | Options and locate the template under fxoi<!|iGY
* the Source Creation and Management node. Right-click the template and choose Ag4Ga?&8ec
* Open. You can then make changes to the template in the Source Editor. -6~y$c&c
*/ 1.95 ^8
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package com.tot.count; YaNH.$.:
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/** L}jF#*Q%
* vG<pc_ak
* @author Tq\~<rEo
*/ d1TdH s\
public class CountBean { Jg|cvu-+
private String countType; s\C8t0C
int countId; it\DZGsg
/** Creates a new instance of CountData */ $S=~YzO
public CountBean() {} 2Jo~m_
public void setCountType(String countTypes){ Z 5)_B,E:X
this.countType=countTypes; ey\m)6A$
} m&`(pf4A
public void setCountId(int countIds){ Z2rzb{oS}
this.countId=countIds; JYg% ~tW'
} t.E4Tqzc>
public String getCountType(){ oO#xx)b
return countType; ]KXMGH_
} G=Hf&l
public int getCountId(){ y5/'!L)g
return countId; 45+%K@@x
} pFJQ7Jlx
} ! FR%QGn1
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CountCache.java )W1(tEq59
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/* -!|WZ
* CountCache.java :GQIlA8cF$
* .5Knb c
* Created on 2007年1月1日, 下午5:01 )XP#W|;
* nJleef9
* To change this template, choose Tools | Options and locate the template under )>y
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* the Source Creation and Management node. Right-click the template and choose f{igW?Ho
* Open. You can then make changes to the template in the Source Editor. p`:*mf
*/ $Eio$TI
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package com.tot.count; >sQ2@"y)s2
import java.util.*; w!WRa8C
/** }U%^3r-
* .~q)eV
* @author ;NH~9# t:
*/ !6zyJc@01
public class CountCache { T3Frc ]6,4
public static LinkedList list=new LinkedList(); SLtSqG7~
/** Creates a new instance of CountCache */ izPh1YA
public CountCache() {} w{3Q( =&
public static void add(CountBean cb){ pd4cg?K
if(cb!=null){ g@@&sB-A"
list.add(cb); l] _b;iux
} gwSN>oj
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} /Fv/oY
} 0%s3Mp6H
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CountControl.java Q PFeBl
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/* Gz>Lqd
* CountThread.java |1(rr%
* EJZ@p7*Oj
* Created on 2007年1月1日, 下午4:57 M%$DT
* ?wd|G4.Vo
* To change this template, choose Tools | Options and locate the template under I?a8h`WS+
* the Source Creation and Management node. Right-click the template and choose ,AH0*L
* Open. You can then make changes to the template in the Source Editor. 4K9Rpm
*/ 'aD6>8/Hj
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package com.tot.count; z,{e]MB)M
import tot.db.DBUtils; N5nvL)a~
import java.sql.*; >dpbCPJ9[
/** Ag0]U
* yjEI/9_
* @author $ph0ag+
*/ [kbC'Eh*
public class CountControl{ -IBO5;2_
private static long lastExecuteTime=0;//上次更新时间 x*.Ye5Jb
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 Yd'H+r5b
/** Creates a new instance of CountThread */ ajn-KG!A
public CountControl() {} }A{_L6qx
public synchronized void executeUpdate(){ of9q"h
Connection conn=null; ~~PgF"v
PreparedStatement ps=null; M@|w[ydQG
try{ 8HMo.*Ti9
conn = DBUtils.getConnection(); 3p=vz'
conn.setAutoCommit(false); rdO@X9z
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); (/"thv5vT{
for(int i=0;i<CountCache.list.size();i++){ Bvz62?
CountBean cb=(CountBean)CountCache.list.getFirst(); Wk@
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CountCache.list.removeFirst(); q0&Wk"X%rr
ps.setInt(1, cb.getCountId()); <rNtY ,
ps.executeUpdate();⑴ ht?CHUu
//ps.addBatch();⑵ 4d!S#zx
} f1A_`$>
//int [] counts = ps.executeBatch();⑶ ,I]7g4~
conn.commit(); Oqpp=7
}catch(Exception e){ VS?dvZ1cC
e.printStackTrace(); P:
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} finally{ L 5+J
^
try{ U,e'ZRU6
if(ps!=null) { Bn\l'T
ps.clearParameters(); ],n%Xp
ps.close(); i 'qMi~{
ps=null; 0pD
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} < CDA"
}catch(SQLException e){} z^r|3;
DBUtils.closeConnection(conn); m$,,YKhh
} Rab#7Q16Q8
} '9qn*H`'
public long getLast(){ /I`3dWL
return lastExecuteTime; 1t+%Gv^sK
} tJ"az=?
public void run(){ Yi 6Nw+$
long now = System.currentTimeMillis(); Rho5s@N 7
if ((now - lastExecuteTime) > executeSep) { @0$}?2
//System.out.print("lastExecuteTime:"+lastExecuteTime); C` pp
//System.out.print(" now:"+now+"\n"); O@s{uZ|A6
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); N[pZIH5ho=
lastExecuteTime=now; 5.wiTy
executeUpdate(); lr WLN
} e#.\^
else{ E#8_hT]5
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); gI)u}JX
} R2l[Q){!
} rJDnuR
} 2}w#3K
//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 )R~aA#<>
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类写好了,下面是在JSP中如下调用。 0Q'v HZ"
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<% tw=K&/@^O
CountBean cb=new CountBean(); x=.tiM {#
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); S_2"7
CountCache.add(cb); (#$$nQj
out.print(CountCache.list.size()+"<br>"); F"'n4|q4n
CountControl c=new CountControl(); `fz,Lh*v
c.run(); =`-|&
out.print(CountCache.list.size()+"<br>"); =+<d1W`>0
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