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: \/jr0):
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CountBean.java ]P TTI\n
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/* u7u8cVF
* CountData.java l`2X'sw[/
* I/bED~Z:a
* Created on 2007年1月1日, 下午4:44 QZBXI3%#s
* PXGS5,
* To change this template, choose Tools | Options and locate the template under ]McLace&
* the Source Creation and Management node. Right-click the template and choose ]1 #& J(
* Open. You can then make changes to the template in the Source Editor. gmfux
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*/ NF1e>O:a<
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package com.tot.count; i0uBb%GMT
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/** 0(s0<9s%
* d\`A
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* @author 0lNVQxG
*/ 7z
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public class CountBean { B$k<F8!%
private String countType; 8T'=lTJ
int countId; L!E/ )#{
/** Creates a new instance of CountData */ =R#K`H66j
public CountBean() {} MN2#
public void setCountType(String countTypes){ BRP9j
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this.countType=countTypes; Q5e ,[1
} %t0Fx
public void setCountId(int countIds){ omM*h{z$$
this.countId=countIds; buo_H@@p{s
} rt%.IQdY
public String getCountType(){ .~V0>r~my
return countType; :X[(ymWNE
} KQ3]'2q
public int getCountId(){ b
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return countId; @v9PI/c
} C
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} S .rT5A[
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CountCache.java TX]4Y953D
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/* "U34D1I)#
* CountCache.java i^(_Gk
* ;C%40;Q
* Created on 2007年1月1日, 下午5:01 59";{"sw
* 4KE"r F
* To change this template, choose Tools | Options and locate the template under SU"-%}~O#,
* the Source Creation and Management node. Right-click the template and choose CG IcuHp
* Open. You can then make changes to the template in the Source Editor. $]4^ENkI
*/ BQv+9(:fQB
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package com.tot.count; s+>""yi
import java.util.*; _`WbR&d2Id
/** *
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* fGJPZe
* @author k
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*/ 3ik
public class CountCache { .ag4i;hS8
public static LinkedList list=new LinkedList(); i 8I%}8
/** Creates a new instance of CountCache */ ;HM&
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public CountCache() {} ~#iRh6^98
public static void add(CountBean cb){ KzZ!
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if(cb!=null){ >2`)S{pBD
list.add(cb); C>Qgd9
} ^.,pq?_
} ilQR@yp*
} Qvs}{h/
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CountControl.java o=?sM q1<
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/* $ud5bT{n
* CountThread.java DW@PPvfs
* y]9
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* Created on 2007年1月1日, 下午4:57 !8vHN=)z
* ys:1%D,,_
* To change this template, choose Tools | Options and locate the template under `pzp(\lc
* the Source Creation and Management node. Right-click the template and choose ?yzhk7j7
* Open. You can then make changes to the template in the Source Editor. ,St#/tu
*/ b9[;qqq@'
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package com.tot.count; _*6nTSL
import tot.db.DBUtils; r_T\%
import java.sql.*; ZA zn-n
/** T F&xiL^
* Z}.N4 /
* @author
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*/ |$#u~<r_
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public class CountControl{ Ol:&cX3G
private static long lastExecuteTime=0;//上次更新时间 KDgJ~T
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 F{ J>=TC
/** Creates a new instance of CountThread */ Ae:(_UJz
public CountControl() {} oC>e'_6_b
public synchronized void executeUpdate(){ npg.*I/>
Connection conn=null; }kI-UEn$EP
PreparedStatement ps=null; on $?c
try{ /HgdTyR)
conn = DBUtils.getConnection(); Oi&.pY:X-
conn.setAutoCommit(false); KgX~PP>
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); q=ZLSBZ
for(int i=0;i<CountCache.list.size();i++){ %TxFdF{A
CountBean cb=(CountBean)CountCache.list.getFirst(); 8I04Nx
CountCache.list.removeFirst(); oAe]/ j$
ps.setInt(1, cb.getCountId()); +ZtqR
ps.executeUpdate();⑴ n(,b$_JK7
//ps.addBatch();⑵ V0z.w:-
} vGO- a2Z
//int [] counts = ps.executeBatch();⑶ Y8`4K* 58%
conn.commit(); W$ #FM$U
}catch(Exception e){ 8AT;9wZqt
e.printStackTrace(); |{+D65R
} finally{ v9INZ1# v
try{ 9=pG$+01OR
if(ps!=null) { g}0}$WgH:
ps.clearParameters(); 1Vt7[L*
ps.close(); _ 0%sYkUc
ps=null; qI\qpWS\
} ii0AhQ
}catch(SQLException e){} q$e2x=?
DBUtils.closeConnection(conn); EcrM`E#kaZ
} u _s
} v'Gqdd-#)
public long getLast(){ Zalgg/.
return lastExecuteTime; Kvv&# eO\
} LGKkT?fcSC
public void run(){ L=3^A'|
long now = System.currentTimeMillis(); @26H;
if ((now - lastExecuteTime) > executeSep) { AZt~ \qf
//System.out.print("lastExecuteTime:"+lastExecuteTime); G+
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//System.out.print(" now:"+now+"\n"); [c]X)
@#S
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); #o_`$'>
lastExecuteTime=now; 12DMb9_rp
executeUpdate(); -}@3,G
} S{{D G
else{ Cq;t;qN,nQ
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); d_gm'
} F=yrqRS=
} +r *f2\S
} 5:E7nqsNhq
//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 kM|akG
G*uy@s:
类写好了,下面是在JSP中如下调用。 e*jt(p[Ge
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<% rc1EJ(c
CountBean cb=new CountBean(); e@*Gnh<&
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); u&?J+
CountCache.add(cb); ]78I
out.print(CountCache.list.size()+"<br>"); *5 ]fjh{
CountControl c=new CountControl(); g
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c.run(); ZN-J!e"`
out.print(CountCache.list.size()+"<br>"); )Yz`
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