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: []u!piW
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CountBean.java Ot(EDa9}IJ
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/* ,g/ UPK8K=
* CountData.java 9WHkw@<R+
* X3q'x}{
* Created on 2007年1月1日, 下午4:44 }G-qOt
* psYfz)1;
* To change this template, choose Tools | Options and locate the template under rYc?y
* the Source Creation and Management node. Right-click the template and choose (z"Cwa@e
* Open. You can then make changes to the template in the Source Editor. >yT:eG
*/ =WN6Fj`
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package com.tot.count; CjIkRa@!x
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/** %(n4`@
* \ar.(J
* @author koaH31Q
*/ ZfMJU
public class CountBean { XD*$$`+#
private String countType; B9+oI cO
int countId; P 0,]Ud
/** Creates a new instance of CountData */ 9B<y w.
public CountBean() {} RJ@d_~%U
public void setCountType(String countTypes){ DGp'Xx_8
this.countType=countTypes; 7 +?
} X8Gw8^t
public void setCountId(int countIds){ A4'vJk
this.countId=countIds; "bC8/^
} ?2Bp^3ytJ
public String getCountType(){ !dmI}<@&k
return countType; 1{"e'[L
} Lw-)ijBW
public int getCountId(){ cC>.`1:
return countId; Km-lWreTH
} 377$c;4F
} e}aD<EG
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CountCache.java R0{n0Br
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/* TN` pai0
* CountCache.java jtl7t59R
* l HZf'P_Wx
* Created on 2007年1月1日, 下午5:01 o#E
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* -rU *)0PR
* To change this template, choose Tools | Options and locate the template under v%B^\S3)
* the Source Creation and Management node. Right-click the template and choose e8P
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* Open. You can then make changes to the template in the Source Editor. ~D
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*/ _RhCVoeB
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package com.tot.count; |9}G
import java.util.*; Z @j0J[s
/** [L9e.n1
* p`XI (NI
* @author =q>eoXp
*/ CJ
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public class CountCache { KXYq|w
public static LinkedList list=new LinkedList(); \@gs8K#
/** Creates a new instance of CountCache */ !)
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public CountCache() {} XKMJsEPsW
public static void add(CountBean cb){ `/0X].s#o
if(cb!=null){ v@< "b U
list.add(cb); FWPkvL
} #2Mz.=#G
} nwW`Q>+#U
} 0
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CountControl.java ~pwp B2c
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/* 8(&C0_yD
* CountThread.java b\H~Ot[i
* Zj!S('hSY
* Created on 2007年1月1日, 下午4:57 &eyFApM[Z
* K*p^Gs,
* To change this template, choose Tools | Options and locate the template under mtmtOG_/=
* the Source Creation and Management node. Right-click the template and choose =3""D{l
* Open. You can then make changes to the template in the Source Editor. #^#N%_8
*/ eEupqOF*:W
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package com.tot.count; JF!!)6!2#
import tot.db.DBUtils; 8tLkJOu
import java.sql.*; !!dNp5h`
/** }_XKO\
* SyX>zN!
* @author 'szkn0
*/ \)`\F$CF
public class CountControl{ L}x"U9'C
private static long lastExecuteTime=0;//上次更新时间 ;k!bv|>n
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 >:h
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/** Creates a new instance of CountThread */ rOH8W
public CountControl() {} naM4X@jl
public synchronized void executeUpdate(){ +g\u=&<6
Connection conn=null; a+,)rY9
PreparedStatement ps=null; 6BNOF66kH
try{ D",ZrwyJ
conn = DBUtils.getConnection(); J'Gn M?M
conn.setAutoCommit(false); 3| g'1X}
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); b8Y1 .y"#
for(int i=0;i<CountCache.list.size();i++){ D)f hk!<
CountBean cb=(CountBean)CountCache.list.getFirst(); (9@6M8A
CountCache.list.removeFirst(); 1% EIP-z
ps.setInt(1, cb.getCountId()); vpTS>!i
ps.executeUpdate();⑴ a!xKS8-S==
//ps.addBatch();⑵ # 1I<qK
} &+JV\
//int [] counts = ps.executeBatch();⑶ bWG}>{fj
conn.commit(); *>zr'Tt,W
}catch(Exception e){ O. @_2
e.printStackTrace(); Vg&`f
} finally{ `{8Sr)
try{ H&`p9d*(e
if(ps!=null) { 4s.wQ2m
ps.clearParameters(); %GjF;dJ
ps.close(); h"M}Iz~|V?
ps=null; `N
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} Cm(Hu
}catch(SQLException e){} y!
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DBUtils.closeConnection(conn); a'XCT@B
} P[aB}<1f0
} Vad(PS0
public long getLast(){ ~Og'IRf
return lastExecuteTime; IiS1ubNtZ
} :n{rVn}G
public void run(){ @ U:WWTzf
long now = System.currentTimeMillis(); sw8Ic\vT
if ((now - lastExecuteTime) > executeSep) { o#Rao#bD:
//System.out.print("lastExecuteTime:"+lastExecuteTime);
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//System.out.print(" now:"+now+"\n"); 5qR76iH)/
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); ,5H$Tm,6\S
lastExecuteTime=now; ayHI(4!$j
executeUpdate(); |]Pigi7y-
} #li;L
else{ ^FF{71;
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); jZe]zdml
} p"JITH:G
} hFyN|Dqhds
} }DY^a'wJ-
//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 boJQ3Xc
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类写好了,下面是在JSP中如下调用。 SQW A{f
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<% Cf2rRH
CountBean cb=new CountBean(); YtxBkKiJ2V
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); Z;SRW92@
CountCache.add(cb); UFC.!t-Z
out.print(CountCache.list.size()+"<br>"); $1#|<|
CountControl c=new CountControl(); ^ D?;K8a-l
c.run(); _Ev"/%
out.print(CountCache.list.size()+"<br>"); X*}S(9cg\i
%>