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: =TP(
UJ
]0B|V2D#e
CountBean.java *[eL~oN.c
ySbqnw'
/* W2;N<[wa<u
* CountData.java |KY EK|
* "&Qctk`<P
* Created on 2007年1月1日, 下午4:44 ?8,%LIQ?
* rC_*sx
r^
* To change this template, choose Tools | Options and locate the template under <P%}|@
* the Source Creation and Management node. Right-click the template and choose '<iK*[NW
* Open. You can then make changes to the template in the Source Editor. qEUT90
*/ ._z'g_c(
QMo}W{D
package com.tot.count; qW_u
X~Rl 6/,
/** CJaKnz
* 3ew8m}A{O
* @author fU2qrcVu
*/ ?@6/Alk
public class CountBean { |DF9cd^
private String countType; iv(5&'[p
int countId; utlpY1#q/
/** Creates a new instance of CountData */ r'BAT3
public CountBean() {} 'j%F]CK
public void setCountType(String countTypes){ #kkY@k$4
this.countType=countTypes; RE 3Z%;'
} 2h
{q h
public void setCountId(int countIds){ E3/:.t
this.countId=countIds; 9^F2$+T[:
} 9H]_4?aX
public String getCountType(){ D~K;~nI
return countType; Ap\AP{S4
} rAQF9O[
public int getCountId(){
,%#
return countId; EA<}[4#jS
} |r RG=tG_'
} n,M)oo1G
^4v*W;Q
CountCache.java T_<BVM
c:M$m3Cs?
/* 02JL*
* CountCache.java ?lCd{14Mkh
* N?4q
* Created on 2007年1月1日, 下午5:01 RAs0]K
* io4A>>W==/
* To change this template, choose Tools | Options and locate the template under tZWrz
e^
* the Source Creation and Management node. Right-click the template and choose Fs/?
* Open. You can then make changes to the template in the Source Editor. IxDWJ#k
*/ zGcqzYbuA
(3,.3)%`
package com.tot.count; &B{8uge1
import java.util.*; |-2}j2'
/** IF
k
* &217l2X
/
* @author `BZ&~vJ_
*/ |I[7,`C~
public class CountCache {
'3l$al:H^
public static LinkedList list=new LinkedList(); 3mt%!}S
/** Creates a new instance of CountCache */ 6\dX
public CountCache() {} Md;/nJO~{
public static void add(CountBean cb){ VU!w!GN]Y
if(cb!=null){ -[#n+`M
list.add(cb); M"^K0 .
} yfjXqn[Z4
} iy5R5L2
} w5~i^x
ek-!b!iI
CountControl.java t]_S
6a}r( yP
/* ySNV^+
* CountThread.java }3/~x
* J>S3sP
* Created on 2007年1月1日, 下午4:57 *ftC_v@p5
* h!]"R<QQdu
* To change this template, choose Tools | Options and locate the template under X.|Ygx
* the Source Creation and Management node. Right-click the template and choose v1[_}N9f>H
* Open. You can then make changes to the template in the Source Editor. 0^ !Gib
*/ hY\{|
nZvU'k:
package com.tot.count; J0<p4%Cf
import tot.db.DBUtils; f5dR 5G
import java.sql.*; l`n5~Fs
/** a,Kky^B
* q7]>i!A
* @author R e:T9K'e
*/ /-*hjX$n
public class CountControl{ d;suACW
private static long lastExecuteTime=0;//上次更新时间 0my9l;X
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 ML!9:vz
/** Creates a new instance of CountThread */ {/M\Q@j
public CountControl() {} 7|D|4!i2Y
public synchronized void executeUpdate(){ L-'k7?%(
Connection conn=null; qJs[i>P[W
PreparedStatement ps=null; p%RUHN3G[
try{ oFg'wAO.
conn = DBUtils.getConnection(); }N3`gCy9eN
conn.setAutoCommit(false); XdIah<F2
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); JAb$M{t
for(int i=0;i<CountCache.list.size();i++){ >2-F2E,
CountBean cb=(CountBean)CountCache.list.getFirst(); Z^6#4Q]YC
CountCache.list.removeFirst(); CUhV$A#oo
ps.setInt(1, cb.getCountId()); *=nO
ps.executeUpdate();⑴ 2*[Un(
//ps.addBatch();⑵ @5Qoi~o
} F,Fo}YQX
//int [] counts = ps.executeBatch();⑶ fNhT;Bux
conn.commit(); c;V D}UD'
}catch(Exception e){ P1d,8~;
e.printStackTrace(); 03E3cp"
} finally{ C!UEXj`l9
try{ 1MQ/r*(
if(ps!=null) { DzDj)7
ps.clearParameters(); 1$["79k
ps.close(); 23E0~O
ps=null; 5d
5t9+t
} hLA;Bl
}catch(SQLException e){} GgdlVi 2
DBUtils.closeConnection(conn); APHPN:v
} h(:<(o@<
} VO9f~>`(
public long getLast(){ D!l8l49hLu
return lastExecuteTime; g,?\~8-c
} !k h{9I>M
public void run(){ $N\+,?
long now = System.currentTimeMillis(); M/w{&&
if ((now - lastExecuteTime) > executeSep) { gX/NtO%
//System.out.print("lastExecuteTime:"+lastExecuteTime); EzP#Mnz^
//System.out.print(" now:"+now+"\n"); bXl8v
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); lP0k:
lastExecuteTime=now; iSd?N}2,I
executeUpdate(); m`9^.>]P
} kMS5h~D[
else{ 0eA5zFU7
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); b>=7B6 Aw
} m3?e]nL4W
} hAa[[%wPhU
} u9>6|w+
//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 T +\ B'"
,P{HE8.
类写好了,下面是在JSP中如下调用。 v72,h
?'+8[OHiF^
<% FW^.m?}|
CountBean cb=new CountBean(); n0FYfqH
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); + U5U.f%
CountCache.add(cb); +u#Sl)F
out.print(CountCache.list.size()+"<br>"); D=9}|b/
CountControl c=new CountControl(); V_M@g;<o
c.run(); SQIdJG^:
out.print(CountCache.list.size()+"<br>"); 0^iJlR2
%>