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: Kob,}NgqZ
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CountBean.java [p`5$\e
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/* K SOD(
* CountData.java y5m2u8+
* l&qCgw
* Created on 2007年1月1日, 下午4:44 _"yA1D0d_
* bD:0k.`
* To change this template, choose Tools | Options and locate the template under L1/`/
* the Source Creation and Management node. Right-click the template and choose Cg]),S
* Open. You can then make changes to the template in the Source Editor. wL
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*/ '= fk;AiQ
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package com.tot.count; I_u/
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/** @&O4a2+
* HRDpFMA/~
* @author uy3<2L#.
*/ wAprksZL#
public class CountBean { &gY) x{
private String countType; L8PX SJ
int countId; tMiIlf!>p
/** Creates a new instance of CountData */ }\7UU?@ n
public CountBean() {} ~!r;?38V`
public void setCountType(String countTypes){ 4#0 3x:/<\
this.countType=countTypes; =ZIT!B?4
} f=R+]XPzz
public void setCountId(int countIds){ crP2jF!
this.countId=countIds; d"#Zp
} j"69uj` R
public String getCountType(){ r%ES#\L6+|
return countType; "/i$_vl
} - Fbp!*.
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public int getCountId(){ YoKyiO!
return countId; UlE%\L0GD&
} EaO@I.[
} DdgiY9a.
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CountCache.java :V)jm`)#+
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/* =79R;|5
* CountCache.java Z,38eQpM
* 0d9z8y
* Created on 2007年1月1日, 下午5:01 -Qn7+?P
* ]19VEH
* To change this template, choose Tools | Options and locate the template under 2L^)k?9>g+
* the Source Creation and Management node. Right-click the template and choose @ivd|*?k0
* Open. You can then make changes to the template in the Source Editor. L9D`hefz
*/ d7X&3L%Oq
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package com.tot.count; p%"dYH%]&0
import java.util.*; x.?5-3|d$
/** ,JV0ib,
* RU:Rt'
* @author e /JQ #A
*/ %x$U(I}
public class CountCache { y~
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public static LinkedList list=new LinkedList(); `um,S
/** Creates a new instance of CountCache */ ^hC'\09=c
public CountCache() {} 2ndn8_l
public static void add(CountBean cb){ \j>7x
if(cb!=null){ 37/n"\4
list.add(cb); `@h|+`h
} +tqErh?Al
} 85GIEUvH/
} %T{]l;5
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CountControl.java AC)
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/* =^nb+}Nz(
* CountThread.java _95296
* DYD<?._I
* Created on 2007年1月1日, 下午4:57 .w9LJ
* BPba3G9H
* To change this template, choose Tools | Options and locate the template under Ic#xz;elM
* the Source Creation and Management node. Right-click the template and choose JQ&t"`\k
* Open. You can then make changes to the template in the Source Editor. u]J@65~'b
*/ *x"80UXL
#.bW9j/
package com.tot.count; $"^K~5Q
import tot.db.DBUtils; qos7u91z
import java.sql.*; u*l|MIi6J
/** L_8zZ8 o
* Z'JS@dV
* @author B[t^u\Fk
*/ TC\+>LXiZ
public class CountControl{ 9t"Rw ns
private static long lastExecuteTime=0;//上次更新时间 ?['!0PF
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 }vd*eexA
/** Creates a new instance of CountThread */ %a;#]d
public CountControl() {} RdTM5ANT
public synchronized void executeUpdate(){ =Ph8&l7~sp
Connection conn=null; ut{T:kT
PreparedStatement ps=null; j9+$hu#a
try{ _!\d?]Ya
conn = DBUtils.getConnection(); +2~kHrv
conn.setAutoCommit(false); (\9`$
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); e#(Ck{e
for(int i=0;i<CountCache.list.size();i++){ X
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CountBean cb=(CountBean)CountCache.list.getFirst(); Kx__&a
CountCache.list.removeFirst(); &XP(D5lf`B
ps.setInt(1, cb.getCountId()); Bh>L"'.2
ps.executeUpdate();⑴ d8j1L/e
//ps.addBatch();⑵ J-F".6i5
} G 6sK3K
//int [] counts = ps.executeBatch();⑶ XIeLu"TSL
conn.commit(); ~Iu! B
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}catch(Exception e){ ggr
e.printStackTrace(); ;;Q^/rkC
} finally{ )O]T}eI
try{ WSkGVQu
if(ps!=null) { =l,P'E
ps.clearParameters(); 0B
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ps.close(); xt{'Be&Ya+
ps=null; H",B[
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} &NE e-cb[
}catch(SQLException e){} EdJL&*
DBUtils.closeConnection(conn); )D)5
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} /:&!o2&1H
} C6_(j48&
public long getLast(){ ;?-AFd\i
return lastExecuteTime; 24mdhT|
} H"C'<(4*\
public void run(){ 5,RUPaE
long now = System.currentTimeMillis(); @fL ^I&++
if ((now - lastExecuteTime) > executeSep) { (!os&/",
//System.out.print("lastExecuteTime:"+lastExecuteTime); uy'ghF
//System.out.print(" now:"+now+"\n"); W?
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// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); Qw5nfg3T
lastExecuteTime=now; Wgq|Q*
executeUpdate(); OG,P"sv
} sGvbL-S-f:
else{ `&$8/_`
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); S:\i
M:
} c8qr-x1HG
} !liV Y]
} 30Q
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//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 :QCL9QZ'
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类写好了,下面是在JSP中如下调用。 #x%'U}sF
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<% L"L3n,%F
CountBean cb=new CountBean(); &J[a.:..
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); 8s%/5v"
CountCache.add(cb); ^S9y7b^;r
out.print(CountCache.list.size()+"<br>"); 4JSPD#%f
CountControl c=new CountControl(); mYBEjZB
c.run(); 5sD,gZ7
out.print(CountCache.list.size()+"<br>"); g;IlS*Ld
%>