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: u$
vLwJ| o
Qqd +=mgc
CountBean.java 5r0Sl89J
M2A3]wd2a
/* z-|d/#h
* CountData.java >?{>
!#1
* }]pO R&o
* Created on 2007年1月1日, 下午4:44 YCBUc<)
* 9Z:pss@
* To change this template, choose Tools | Options and locate the template under ?' $}k
* the Source Creation and Management node. Right-click the template and choose ai)?RF
* Open. You can then make changes to the template in the Source Editor. ?aZ\Dg{
*/ ^Uldyv/
^.[+)0I
package com.tot.count; PkK#HD
'fIG$tr9X
/** p S!N<;OWr
* &RlYw#*1.
* @author 2yV{y#\
*/ }
ejc
public class CountBean { a]x\e{
private String countType; <h~_7Dn
int countId; (!<G` ;}u
/** Creates a new instance of CountData */ peU1
t:k?
public CountBean() {} 1gH>B5`
public void setCountType(String countTypes){ %U$%x
this.countType=countTypes; Z15b'^)?9
} h='@Q_1Sb
public void setCountId(int countIds){ =!2(7Nr
this.countId=countIds; 9riKSp:5
} ":^cb =
public String getCountType(){ I\VC2U
return countType; LMYO>]dg
} ptpu
u=3"
public int getCountId(){ Oc^bbC
return countId;
av!~B,
} Y.8mgy>
} ]m""ga
86f/R
c
CountCache.java +tFl
&M+fb4:_
/* ,m.IhnCV\
* CountCache.java T8J[B( )L
* C AF{7 `{
* Created on 2007年1月1日, 下午5:01 qXQ7Jg9
* 0t}&32lL&
* To change this template, choose Tools | Options and locate the template under .cm$*>LW:x
* the Source Creation and Management node. Right-click the template and choose :S{+|4pH
* Open. You can then make changes to the template in the Source Editor. Qu@T}Ci
*/ ,(CIcDJ2U_
T>s3s5Y
package com.tot.count; b$'}IWNV
import java.util.*; : w 4Sba3
/** 'x!5fAy
* [O(8izv
* @author nc.X+dx:
*/ 8_F 5c@7
public class CountCache { xA2"i2k9
public static LinkedList list=new LinkedList(); {QTnVS't 0
/** Creates a new instance of CountCache */ -?68%[4lm_
public CountCache() {} cp>1b8l6?
public static void add(CountBean cb){ "i ;c )ZP
if(cb!=null){ ,L}
list.add(cb); %2D9]L2Up
} T#e ;$\
} d%:
} m|w-}s,
YCd[s[
CountControl.java 6vQCghI
4R/cN'-
/* 9vZD?6D,n
* CountThread.java /G h?z
* 5J4'\M
* Created on 2007年1月1日, 下午4:57 8vLaSZ="[
* e1j3X\ \
* To change this template, choose Tools | Options and locate the template under +bw>9VmG
* the Source Creation and Management node. Right-click the template and choose sox0:9Oqnf
* Open. You can then make changes to the template in the Source Editor. (/r l\I
*/ ;L458fYs
_3YuPMaN
package com.tot.count; fGtUr_D
import tot.db.DBUtils; 9=J+5V^qD<
import java.sql.*; (93+b%^[
/** <!s+X_^
* eiV[y^?
* @author pp#xN/V#a
*/ Pu=,L#+F N
public class CountControl{ qQu}4Ye>
private static long lastExecuteTime=0;//上次更新时间 #ONad0T;
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 1sqBBd"=PY
/** Creates a new instance of CountThread */ 69{BJ]q
public CountControl() {} j<-#a^jb
public synchronized void executeUpdate(){ 6{ql.2
Fa
Connection conn=null; W/3,vf1
PreparedStatement ps=null; 0#AS>K5
try{ bZE;}d
conn = DBUtils.getConnection(); N<|_tC+ct
conn.setAutoCommit(false); q*|H*sS
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); IezOal
for(int i=0;i<CountCache.list.size();i++){ Y%FQ]Q=+
CountBean cb=(CountBean)CountCache.list.getFirst(); \<}4D\qz
CountCache.list.removeFirst(); pu:Ie#xTDf
ps.setInt(1, cb.getCountId()); RpAqnDX)
ps.executeUpdate();⑴ &p)]Cl/`
//ps.addBatch();⑵ gkJL=,
} sw={bUr6G`
//int [] counts = ps.executeBatch();⑶ [\ M$a|K
conn.commit(); e'FBV[e
}catch(Exception e){ Ua>lf8w<
e.printStackTrace(); /!l$Y?
} finally{ <QlpIgr
try{ Q M#1XbT
if(ps!=null) { q`HuVilNH
ps.clearParameters(); ''{REFjK7
ps.close(); UE-<
ps=null; h"y~!NWn
} GBl[s,g[|
}catch(SQLException e){} O'Q,;s`uC
DBUtils.closeConnection(conn); <t&Qa~mA
} '~9w<dSB!r
} r;9 V7C
public long getLast(){ &qzy?/i8
return lastExecuteTime; ?Rk[P
cX<
} _o T+x%i
public void run(){ #P1U]@
long now = System.currentTimeMillis(); +MqJJuWB
if ((now - lastExecuteTime) > executeSep) { 1=h5Z3/fj
//System.out.print("lastExecuteTime:"+lastExecuteTime); Uc,J+j0F
//System.out.print(" now:"+now+"\n"); y`i?Qo3
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); '
<?=!&\D
lastExecuteTime=now; h@NC#Iod
executeUpdate(); 8C8S)
;
} \/<VJB
uV
else{ 8Th,C{
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); \QC{38}
} ~tt\^:\3~S
} * 30K}&T
} [|1I.AZ{
//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 Li}5aK
z`t~N
类写好了,下面是在JSP中如下调用。 +|d]\WlJ
1s@QsZ3
<% _qf39fM;\
CountBean cb=new CountBean(); ,lA@C2c
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); +pme]V|<
CountCache.add(cb); Nj3iZD|
out.print(CountCache.list.size()+"<br>"); 0&|0l>wy.
CountControl c=new CountControl(); dt:$:,"
c.run(); cjPXrDl{\
out.print(CountCache.list.size()+"<br>"); {Ba&
%>