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: _y>drvg
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CountBean.java ~UQ<8`@a
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/* +opym!\
* CountData.java O7LJ-M
* -b8SaLak
* Created on 2007年1月1日, 下午4:44 VYh/URU>
* (4yXr|to}
* To change this template, choose Tools | Options and locate the template under d7QUg6=
* the Source Creation and Management node. Right-click the template and choose s"w^E\>6
* Open. You can then make changes to the template in the Source Editor. GE=S.P;
*/ @"/H
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package com.tot.count; Qy4Pw\
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/** '/9MN;_
* /YJBRU2
* @author J&JZYuuf
*/ D8PC;@m
public class CountBean { L\c3D|
private String countType; I5g|)Y Q
int countId; B1E:P`t
/** Creates a new instance of CountData */ ; !t?*
public CountBean() {} /n>vPJvz
public void setCountType(String countTypes){ G973n
this.countType=countTypes; n<> ^cD
} #DJZ42
public void setCountId(int countIds){ q *Hg-J}
this.countId=countIds; &?5)Jis:
} B~qo^ppVU
public String getCountType(){ /0|1xHs
return countType; \ISg6v{/
} 0]MD?6-
public int getCountId(){ L ed{#+
return countId; j;D$qd'J
} D0kz;X
} Z(R0IW
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CountCache.java Vjo[rUW
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/* =ONM#DxH
* CountCache.java *mWl=J;u
* iCh8e>+
* Created on 2007年1月1日, 下午5:01 rLmc(-q
* 7,Z<PE
* To change this template, choose Tools | Options and locate the template under ZHeq)5C ;f
* the Source Creation and Management node. Right-click the template and choose ;/?w-)n?
* Open. You can then make changes to the template in the Source Editor. 6|3 X*Orn
*/ c{?SFwgd
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package com.tot.count; )Td{}vbIh
import java.util.*; I!1+#0SG
/** #;@I.
* a$^)~2U{
* @author R~[~(`/S
*/ 2Kr>93O
public class CountCache { }opMf6`w
public static LinkedList list=new LinkedList(); HUCJA-OZGL
/** Creates a new instance of CountCache */ >py[g0J
public CountCache() {} d^!3&y&
public static void add(CountBean cb){ 5_L,7\5#
if(cb!=null){ 5|Z8UzL
list.add(cb); F!/-2u5gF
} *HGhm04F{
} v+79#qWK|n
} c9CFGo?)N
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CountControl.java jJt4{c
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/* 5M5vxJ)Lh
* CountThread.java |/%5~=%7
* d&Nji%Ej
* Created on 2007年1月1日, 下午4:57 i^A=nsD`
* P7bb2"_9
* To change this template, choose Tools | Options and locate the template under W$;qhB
* the Source Creation and Management node. Right-click the template and choose ,2 W=/,5A
* Open. You can then make changes to the template in the Source Editor. <]|HGc
*/ .q4$)8[Pg
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package com.tot.count; afD {w*[8
import tot.db.DBUtils; p>3QW3<
import java.sql.*; a;-%C{S9r
/** I\c7V~^hnG
* ONy\/lu|
* @author E.ji;5
*/ #9.%>1{6Y
public class CountControl{ t?Qbi)T=z
private static long lastExecuteTime=0;//上次更新时间 uW FyI"
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 ;PU'"MeB "
/** Creates a new instance of CountThread */ _FcTY5."S
public CountControl() {} UHU ,zgM
public synchronized void executeUpdate(){ aot2F60J,
Connection conn=null; ,RY;dX-#
PreparedStatement ps=null; c|aX4 =Z
try{ W(4$.uZ)
conn = DBUtils.getConnection(); Zby3.=.e
conn.setAutoCommit(false); CQa8I2VF
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ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); cjO%X
for(int i=0;i<CountCache.list.size();i++){ LYd:S
CountBean cb=(CountBean)CountCache.list.getFirst(); oqhJ2
CountCache.list.removeFirst(); xJU]py~o
ps.setInt(1, cb.getCountId()); Q^3{L\6_
ps.executeUpdate();⑴ S&XlMu
//ps.addBatch();⑵ 6\I1J=
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} t?PqfVSq
//int [] counts = ps.executeBatch();⑶ ScD
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conn.commit(); =>evkaj
}catch(Exception e){ 3T,[
e.printStackTrace(); U/cj_}uX
} finally{ jV%=YapF
try{ ]o0]i<:
if(ps!=null) { WvfM.D!
ps.clearParameters(); g"kI1^[nj
ps.close(); UpE+WzY
ps=null; }' Y)"8AIA
} v'Ehr**]+
}catch(SQLException e){} 6~2upy~e
DBUtils.closeConnection(conn); *mJ#|3I<
} p8@&(+z
} J` gG`?
public long getLast(){ V rx,'/IS8
return lastExecuteTime; JsuI&v
} +Ss3Ph
public void run(){ /BQqg08@L
long now = System.currentTimeMillis(); Umz b
if ((now - lastExecuteTime) > executeSep) { >$-YNZA
//System.out.print("lastExecuteTime:"+lastExecuteTime); 4cPZGZ{U
//System.out.print(" now:"+now+"\n"); q165S
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); OgC,oj,!/
lastExecuteTime=now; (EosLn
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executeUpdate(); 8-k`"QI=
} 2fu<s^9dh
else{ :b %2qBv
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); $0 vT_
} xf,A<j(o
} Cc%{e9e*
} {7]maOg>7J
//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 9\WtcLx
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类写好了,下面是在JSP中如下调用。 |W=-/~X
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<% \-[bU6\A\
CountBean cb=new CountBean(); }79jyS-e
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); 2\z|/
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CountCache.add(cb); Y_jc *S
out.print(CountCache.list.size()+"<br>"); D|m3.si
CountControl c=new CountControl(); /VufL+q1
c.run(); gt(p%~
out.print(CountCache.list.size()+"<br>"); srAWet
%>