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: w o9f99
}@6
%yR
CountBean.java uL AXN
%"fKZ
/* ]}y'3aW
* CountData.java f+~!s 2uw
* K8c#/o
* Created on 2007年1月1日, 下午4:44 &J M;jSz
* B;_3IHMO
* To change this template, choose Tools | Options and locate the template under TBT*j&!L
* the Source Creation and Management node. Right-click the template and choose Q
kpmPQK
* Open. You can then make changes to the template in the Source Editor. _oVA0@#n
*/ =6YO!B>7
V3UGx'@^y
package com.tot.count; 'PbA/MN
2=+ ,jX{
/** Ih"Ol(W
* U#
B
* @author AE
_~DZ:%c
*/ E=trJge
public class CountBean { XjU; oh4:.
private String countType; 1zW6Pb
int countId; 7?] p\`
/** Creates a new instance of CountData */ RVx<2,['
public CountBean() {} RL9BB.
public void setCountType(String countTypes){ 6<nO2 GW
this.countType=countTypes; OG`Oi^2
} *X=-^\G
public void setCountId(int countIds){ 3zHiu*2/!
this.countId=countIds; tYa8I/HpT
} MEUqQ4/Gl
public String getCountType(){ AFED YRX
return countType; oFp&j@`k8j
} Z.JTq~`I
public int getCountId(){ l si8?91
return countId; _AHVMsz@
} *JXJ
2
} jp`N%O]6
~!kbB4`WK
CountCache.java D IN
PAyY
-Ma"V
/* $)V4Eu;
* CountCache.java v g]&T
* <
.!3yy
* Created on 2007年1月1日, 下午5:01 'h6RZKG T
* gId+hxFa:r
* To change this template, choose Tools | Options and locate the template under pnU
g:R@
* the Source Creation and Management node. Right-click the template and choose lR!$+atW
* Open. You can then make changes to the template in the Source Editor. C-Z,L#
*/ y"ck;OQD
r~!lD9R~
package com.tot.count; k_B^2=
import java.util.*; 'CX
KphlWs
/** HV(Kz
* T\>=o]
* @author ?Dm&A$r
*/ IpxjP\
public class CountCache { Y')+/<Q2E
public static LinkedList list=new LinkedList(); 7F4]EA^
/** Creates a new instance of CountCache */ 7SCI_8`
public CountCache() {} U?QO'H5
public static void add(CountBean cb){ C0RwW??t
if(cb!=null){ cx|j
_5%i
list.add(cb); )[1m$>
} =j0V/=
} jVz1`\Nje
} %#,BvQz~
~CA+'e%~~
CountControl.java BlUY9`VWh@
$$@Tgkg?o
/* 5kF5`5+Vj
* CountThread.java Tx5L
* G u=Rf`o
* Created on 2007年1月1日, 下午4:57 N5\<w>
* LjH];=R
* To change this template, choose Tools | Options and locate the template under nCrNZ&P
* the Source Creation and Management node. Right-click the template and choose 4jpF^&y7u^
* Open. You can then make changes to the template in the Source Editor. <Yc:,CU
*/ i,'~Ds
oC
[g
package com.tot.count; ezn>3?S
import tot.db.DBUtils; ?P5D!b:(
import java.sql.*; 9\8""-
/** &a`-NRU#
* )~`zjVx_
* @author Ssj'1[%
*/ .\VjS^o&Z&
public class CountControl{ uMI2Wnnc:/
private static long lastExecuteTime=0;//上次更新时间 2B4c:jJ
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 K +~
/** Creates a new instance of CountThread */ 181P;R=}<
public CountControl() {} t]x HM
public synchronized void executeUpdate(){ L!5f*
Connection conn=null; UZ1lI>
PreparedStatement ps=null; ?]t8$^m,;
try{ $?\],T
conn = DBUtils.getConnection(); vZ08/!n
conn.setAutoCommit(false); =9c24j
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); B;m18LDu
for(int i=0;i<CountCache.list.size();i++){ ^Z*_@A _v
CountBean cb=(CountBean)CountCache.list.getFirst(); _VlNZ/V
CountCache.list.removeFirst(); i`Tne3)
ps.setInt(1, cb.getCountId()); 9K49<u0O
ps.executeUpdate();⑴ 0^m02\Li
//ps.addBatch();⑵ /$n${M5!
} <fw[7=_)^
//int [] counts = ps.executeBatch();⑶ @:[/uqL
conn.commit(); [ACYd/
}catch(Exception e){ sJr$[?
e.printStackTrace(); Rww KPE
} finally{ #_E8>;)k
try{ 8[DD=[&
if(ps!=null) { /eI38>v
ps.clearParameters(); Rwr0$_A
ps.close(); =y':VIVJC
ps=null; MwuH.# Ez
} {?C7BClB
}catch(SQLException e){} -X=f+4j
DBUtils.closeConnection(conn); sLTf).xh
} 8]Pf:_e,+
} )S%mKdOm
$
public long getLast(){ Bq!P.%6p4
return lastExecuteTime; '.iUv#j4Sh
} 4uz\Me(
public void run(){ C{c (K!
long now = System.currentTimeMillis(); VHJr+BQ1K/
if ((now - lastExecuteTime) > executeSep) { b#P8Je`;9
//System.out.print("lastExecuteTime:"+lastExecuteTime); ENGw <
//System.out.print(" now:"+now+"\n"); GL /\uq
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); 'g^]ZTxb
lastExecuteTime=now; PC9:nee
executeUpdate(); X)yTx8v4
} JK1b68n
else{ KAe)
X_R7
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); sST6_b
} H&GMq5)B
} 'C[gcp
} b*bR<|dT j
//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 9u:MF0:W
eSvu:euv
类写好了,下面是在JSP中如下调用。 9oaq%Sf
BFMM6-Ve
<%
W6a2I
CountBean cb=new CountBean(); 5Zq- |"|
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); -<|Ebh d3
CountCache.add(cb); LJBoS]~
out.print(CountCache.list.size()+"<br>"); 4TLh'?Xu9
CountControl c=new CountControl(); !0w'S>e
c.run(); ]03!KE
out.print(CountCache.list.size()+"<br>"); ]$z~;\ T
%>