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: ]}R\[F (_%
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CountBean.java ^B2>lx\n
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/* 1R)4[oYN\<
* CountData.java C|c'V-f
* d^X;XVAvP
* Created on 2007年1月1日, 下午4:44 h^ ex?
* D0,U2d
* To change this template, choose Tools | Options and locate the template under 2.O;
* the Source Creation and Management node. Right-click the template and choose i'|rx2]e
* Open. You can then make changes to the template in the Source Editor. xtL_,ug
*/ hKb-l`KO
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package com.tot.count; A P><l@
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/** `,~I*}T>5W
* Kx?3 ]
* @author qve2?,i8hM
*/ D`3m%O(?
public class CountBean { {:c*-+?
private String countType; xn(lkQ6Fm
int countId; w\KO1 Ob
/** Creates a new instance of CountData */ PgAC3%M6
public CountBean() {} b|t` )BF
public void setCountType(String countTypes){ fkWuSGi
this.countType=countTypes; 9mkt.>$
} po+>83/!oq
public void setCountId(int countIds){ HjKj.fV
this.countId=countIds; zC6,m6Dv
} MIasCH>r
public String getCountType(){ 'mj0+c$
return countType; 1HxE0>
} U/&!F
public int getCountId(){ xN0n0
return countId; >5)E\4r-
} A!&p,KfT5+
} A-r-^S0\
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CountCache.java @#Jc!p7)
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/* ! FbW7"yE
* CountCache.java 0V
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* /\_`Pkd3m
* Created on 2007年1月1日, 下午5:01 1pogk0h.:
* N~g@
* To change this template, choose Tools | Options and locate the template under
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* the Source Creation and Management node. Right-click the template and choose ;>Y,b4B;
* Open. You can then make changes to the template in the Source Editor. ,%e.nj9
*/ j`Fsr?]/
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package com.tot.count; ?e9Acc`G5
import java.util.*; 1 *'SP6g
/** U)a}XRS
* x|n2,3%
* @author .ICGGC`O
*/ l'HrU 1_7Y
public class CountCache { gJ cf~@s
public static LinkedList list=new LinkedList(); ta _!
/** Creates a new instance of CountCache */ 5mdn77F_
public CountCache() {} {\
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public static void add(CountBean cb){ ^yg`U(
if(cb!=null){ PpX=~Of~
list.add(cb); 'S\YNLqQ
} @x?7J@:
} #r M/
} ST1PSuC~
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CountControl.java W&dYH 4O
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/* tKgPKWP
* CountThread.java =z^v)=uhp
* 7H~StdL/>
* Created on 2007年1月1日, 下午4:57 i]!CH2\
* `=^;q6f
* To change this template, choose Tools | Options and locate the template under 8?!=/Sc
* the Source Creation and Management node. Right-click the template and choose oUXu;@l
* Open. You can then make changes to the template in the Source Editor. -Wc'k 2oU
*/ AGkk|`
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package com.tot.count; #jn6DL@[{
import tot.db.DBUtils; FI{9k(
import java.sql.*; ,5Jq
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/** &PWz4hZ
* ?khwupdi
* @author
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*/ qwJeeax
public class CountControl{ H/'tSb
private static long lastExecuteTime=0;//上次更新时间 >7.
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private static long executeSep=60000;//定义更新间隔时间,单位毫秒 ;*ebq'D([
/** Creates a new instance of CountThread */ U,S&"`a
public CountControl() {}
*&{M,
public synchronized void executeUpdate(){ eU?SLIof[{
Connection conn=null; .q#2 op
PreparedStatement ps=null; zk= 3L} C
try{ T<kyxbjR
conn = DBUtils.getConnection(); JTB_-J-TU
conn.setAutoCommit(false); e8O[xM
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); m,',luQ
for(int i=0;i<CountCache.list.size();i++){ j/_@~MJBt
CountBean cb=(CountBean)CountCache.list.getFirst(); =FUORj\O
CountCache.list.removeFirst(); i{TErJ{}e
ps.setInt(1, cb.getCountId()); "?a(JC
ps.executeUpdate();⑴ s,>1n0a
//ps.addBatch();⑵ Z'p7I}-qr
} LyR to
//int [] counts = ps.executeBatch();⑶ ?LAKH$t
conn.commit(); G>f-w F6
}catch(Exception e){ ;hU56lfZ)X
e.printStackTrace(); 9v&{;
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} finally{ ?<VahDBS+A
try{ f@Mm{3&.
if(ps!=null) { V4'G%!NY
ps.clearParameters();
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ps.close(); VOH.EK?5
ps=null; l&cYN2T
b
} C^I h"S
}catch(SQLException e){} ciO^2X
DBUtils.closeConnection(conn); `P}T{!P+6
} l1On .s
} @q2If{Tk
public long getLast(){ ] >-#T
return lastExecuteTime; EdxTaR
} zS*GYE(l^
public void run(){ ~t\Hb8o
long now = System.currentTimeMillis(); BoJ@bOe#
if ((now - lastExecuteTime) > executeSep) { 3{B`[$
//System.out.print("lastExecuteTime:"+lastExecuteTime); Iu`eQG
//System.out.print(" now:"+now+"\n"); r#LoBfM;^A
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); . fq[>zG'&
lastExecuteTime=now; Ga0=
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executeUpdate(); #"% ]1={b
} \Ku6gEy
else{ x"0*U9f
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); wQiRj.
} Z[:fqvXQ
} v{9< ATi
} M?pu7wa
//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 '}h[*IB}5
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类写好了,下面是在JSP中如下调用。 Un\h[m
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<% TUzpln
CountBean cb=new CountBean(); vy\;#X!
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); [P`t8
CountCache.add(cb); 3l"7 $B
out.print(CountCache.list.size()+"<br>"); A8Q1x/d(
CountControl c=new CountControl(); |Q2H^dU'rQ
c.run(); &z;F'>"
out.print(CountCache.list.size()+"<br>"); h7mJXS)t|
%>