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: CvmZW$5Yo
qMYR\4"$
CountBean.java LW_Y
mmY~V:,Kd
/* B;4hI?
* CountData.java F<BhN+U
* FePJ8
* Created on 2007年1月1日, 下午4:44 e;x`C
* z%ljEI"<C
* To change this template, choose Tools | Options and locate the template under V5KAiG<d
* the Source Creation and Management node. Right-click the template and choose .
)Fn]x"<
* Open. You can then make changes to the template in the Source Editor. y[qW>
*/ 25ul,t_Du
x)G/YUv76
package com.tot.count; v0X5`VV
)ty
*_@N0
/** [rTV)JsTb
* HT
A-L>Cee
* @author )_+"
*/ F"hi2@/TI
public class CountBean { \_@u"+,$W
private String countType; C,]Q/6'>
int countId; \#tr4g~u
/** Creates a new instance of CountData */ .^@+$}
public CountBean() {} BxZ}YS:
public void setCountType(String countTypes){ ;}f%b E
this.countType=countTypes; C'n 9n!hR
} $0LlaN@e
public void setCountId(int countIds){ FD|R4 V*3
this.countId=countIds; 7 bsW7;C
} z-7F,$
public String getCountType(){ m>:%[vm
return countType; Zu%_kpW
} 54uTu2
public int getCountId(){ 6J%SkuxR
return countId; 8H;TPa
} l*'8B)vN2
} 0)ST_2Ci
9-Ib+/R0
CountCache.java BC@"WlD
H:[z#f|t
/* 7Fy^K;V"
* CountCache.java i":-g"d
* 0QC*Z (
* Created on 2007年1月1日, 下午5:01 GrM~%ng
* l*X5<b9
* To change this template, choose Tools | Options and locate the template under gmLw. |-
* the Source Creation and Management node. Right-click the template and choose Q&QR{?PMD
* Open. You can then make changes to the template in the Source Editor. G)< k5U4
*/ ;F5B)&/B
zv0RrF^
package com.tot.count; Ccc6 ko_
import java.util.*; u'32nf?
/** >F-J}P
*
}U^9(
* @author ww\/$ |
*/ Ok:@F/ v
public class CountCache { |(P>'fat-p
public static LinkedList list=new LinkedList(); 1H[lf
B
/** Creates a new instance of CountCache */ PTePSj1N
public CountCache() {} vG\Wr.h0!=
public static void add(CountBean cb){ $%t{O[(
if(cb!=null){ fmSw%r|pT
list.add(cb); MfL q
h
} "lz!'~im
} ]a:kP,
} /FYa{.Vlr
ol[{1KT{
CountControl.java d>AVUf<o~
Gf%o|kX]
/* P&F)E#Sa
* CountThread.java hCo&SRC/5
* g{D&|qWj
* Created on 2007年1月1日, 下午4:57 n `n3[
* "RShsJZMH
* To change this template, choose Tools | Options and locate the template under C#r`oZS1
* the Source Creation and Management node. Right-click the template and choose aIfog+Lp
* Open. You can then make changes to the template in the Source Editor. /=3g-$o{`
*/ =Q|}7g8o
C$%QVcf
package com.tot.count; >`NM?KP s
import tot.db.DBUtils; L,D!T&B
import java.sql.*; h)<42Y
/** .i. |wY
* 7}lZa~/
* @author e6_.ID'3
*/ _*;cwMne-
public class CountControl{ J%A`M\
private static long lastExecuteTime=0;//上次更新时间 YT3QwN9
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 <r\)hx0ov
/** Creates a new instance of CountThread */ )RkU='lB "
public CountControl() {} BT#>b@Xub
public synchronized void executeUpdate(){
K8+b\k4E
Connection conn=null; cPN7^*
PreparedStatement ps=null; lLJb3[
e.
try{ 5m bs0GL
conn = DBUtils.getConnection(); FQ87[|
S
conn.setAutoCommit(false); 05zHL j
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); 'qP^MdoE%~
for(int i=0;i<CountCache.list.size();i++){ RSi0IfG5
CountBean cb=(CountBean)CountCache.list.getFirst(); K;97/"
CountCache.list.removeFirst(); #0P<#S^7
ps.setInt(1, cb.getCountId()); -j$l@2g
ps.executeUpdate();⑴ q-o>yjT~
//ps.addBatch();⑵ QbNv+Eu5
} (o:CxhV
//int [] counts = ps.executeBatch();⑶ "p;DQ-V
conn.commit(); ,mX|TI<*
}catch(Exception e){ E*I]v
e.printStackTrace(); sogbD9Jc
} finally{ @uE=)mP@
try{ }?~uAU-
if(ps!=null) { EUn"x'
ps.clearParameters(); R P X`2zr
ps.close(); 6f>l~$
ps=null; }ri*e2y)
} 6^aYW#O<Ua
}catch(SQLException e){} ~ghz%${`
DBUtils.closeConnection(conn); UbibGa=
)
} [s34N+vU
} }F`Tp8/&j
public long getLast(){ &`Di cfD
return lastExecuteTime; q5!l(QL.
} i]-gO
public void run(){ mce`1Tjw
long now = System.currentTimeMillis(); iy#OmI>j
if ((now - lastExecuteTime) > executeSep) { =zjUd 5
//System.out.print("lastExecuteTime:"+lastExecuteTime); cMWO_$
//System.out.print(" now:"+now+"\n"); &v-V_.0(H
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); j>Z]J'P
lastExecuteTime=now; {^kG<v.vV
executeUpdate(); j~E +6f\
} SN{*:\>,
else{ -h@0 1
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); 1a$V{Eag
} DqMK[N,0
} pG( knu
} W^ :/0WR
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 h*KHEg"+
G; [AQ:Iy
类写好了,下面是在JSP中如下调用。 ]k:m2$le
6)U&XWH0
<% 3NN'E$"3
CountBean cb=new CountBean(); <VU4rk^=
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); E.`dk.
CountCache.add(cb);
`,Nn4
out.print(CountCache.list.size()+"<br>"); ^B5cNEO
CountControl c=new CountControl(); GeaDaYh#T
c.run(); f4I#a&DO
out.print(CountCache.list.size()+"<br>"); DjzUH{6O
%>