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: :<l(l\MC
Q%61_l
CountBean.java (a0q*iC%
m0+X 109
/* :|3n`,
* CountData.java SnsOuC5Ah
* kYBy\
* Created on 2007年1月1日, 下午4:44 t(YrF,
* j^
VAA\
* To change this template, choose Tools | Options and locate the template under _zq"<Q c
* the Source Creation and Management node. Right-click the template and choose u/3[6MIp
* Open. You can then make changes to the template in the Source Editor. iO)FZ%?"
*/ 4vi P lO
dGU io?
package com.tot.count; AvF:$kG
M}|<#
i7u
/** L P?E
* .'QE o
* @author !PX`sIkT
*/ bM[!E 8dF
public class CountBean { Ergh]"AD6-
private String countType; Y;ytm
#=
int countId; fG2hCP+
/** Creates a new instance of CountData */ B2\R#&X.
public CountBean() {} a[;TUc^I1F
public void setCountType(String countTypes){ MYgh^%w:
this.countType=countTypes; 5 Z+2
} $Fx:w
public void setCountId(int countIds){ :r%Hsur(
this.countId=countIds; <smi<syx
} 41f4zisZ
public String getCountType(){ $\BRX\6(-
return countType; dHp(U
:)
} o";5@NH
public int getCountId(){ UruD&=AMK
return countId; es}j6A1
} EHk(\1!V
} cNX,%
% c[Q_
CountCache.java 7#K%Bo2pG
wLyQ <[$
/* K?[*9Q'\
* CountCache.java Ml`tDt|;
* R[Y]B$XO
* Created on 2007年1月1日, 下午5:01 :<$B o
* y{CyjYpz^
* To change this template, choose Tools | Options and locate the template under _&!%yW@
* the Source Creation and Management node. Right-click the template and choose <i9pJGW
* Open. You can then make changes to the template in the Source Editor. ~Pq(Ta
*/ Q>qx?
g
u~MD?!LV
package com.tot.count; ~ZbEKqni2
import java.util.*; F/c7^
/** l
AF/O5b
* !Z+4FwF
* @author {k.Dy92
*/ L'XX++2
public class CountCache { nO{@p_3mi
public static LinkedList list=new LinkedList(); Rv R,V
/** Creates a new instance of CountCache */ Sn 3@+9J
public CountCache() {} b'\a
4
public static void add(CountBean cb){ /">A3bq
if(cb!=null){ 6")co9
list.add(cb); ;4DqtR"7Y
} *LnY}#
} ,0ZkE}<=w
} uYW9kw>$
tEEeek(!
CountControl.java 99Jk<x
k
0@;kD]Z
/* ZZ 1s}TG
* CountThread.java -&87nR(eW
* VT.BHZ
* Created on 2007年1月1日, 下午4:57 ^<L;"jl%
* 1o5DQ'~n
* To change this template, choose Tools | Options and locate the template under 6n9;t\'Gt
* the Source Creation and Management node. Right-click the template and choose -P!_<\q\l
* Open. You can then make changes to the template in the Source Editor. TUeW-'/1
*/ 7bBOV(/s
56!>}!8!
package com.tot.count; -]=-IiC#
import tot.db.DBUtils; rN3i5.*/t
import java.sql.*; sD V*k4
/** utk'joo
* Vg1!
u+`<
* @author _ PC}`Y'&
*/ =Rnx!E
public class CountControl{ Al?LO;$Pa?
private static long lastExecuteTime=0;//上次更新时间 s^nPSY!
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 ni @Mqb
/** Creates a new instance of CountThread */ CV<@Rgoa
public CountControl() {} 6*@\Qsp615
public synchronized void executeUpdate(){ "52nT
Connection conn=null; mG,%f"b0
PreparedStatement ps=null; &=SP"@D
try{ bJ8~/d]+
conn = DBUtils.getConnection(); DwTqj=l
conn.setAutoCommit(false); @D.]PZf
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); 1iOQ8hD
for(int i=0;i<CountCache.list.size();i++){ Mp;yvatO
CountBean cb=(CountBean)CountCache.list.getFirst(); .BLF7>
M1
CountCache.list.removeFirst(); fneg[K
ps.setInt(1, cb.getCountId()); :v/6k
ps.executeUpdate();⑴ }@Mx@ S
//ps.addBatch();⑵
0>D:
} D8+68_BEM
//int [] counts = ps.executeBatch();⑶ ^Pc>/lY$Q%
conn.commit(); G$\2@RT9[
}catch(Exception e){ BV=L.*
e.printStackTrace(); LM_/:
} finally{ Pw4j?pv2
try{ p_hljgOV
if(ps!=null) { *|c*/7]<
ps.clearParameters(); mPR(4Ol.
ps.close(); t
>89(
k
ps=null; :P$I;YY=A
} ,}&E=5MF\
}catch(SQLException e){} 'TPRGX~&
DBUtils.closeConnection(conn); ?L|Jc_E
} +cAN4
} T7W*S-IW
public long getLast(){ \Fhk>
return lastExecuteTime; hv xvwV1
} z~d\d!u1
public void run(){ )r
O`K
long now = System.currentTimeMillis(); 5BKmp-m
if ((now - lastExecuteTime) > executeSep) { y%T5"p$,
//System.out.print("lastExecuteTime:"+lastExecuteTime); {b@rQCre7
//System.out.print(" now:"+now+"\n"); amI$0
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); &lYKi3}x
lastExecuteTime=now; Zp|LCE"
executeUpdate(); f[)_=T+
} s)]Z*#ZZ
else{ M,[u}Rf^w
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); (]BZ8GOx
} *"E?n>b
} UV>^[/^O
} #&\hgsw/T
//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 tK&.0)*=
)2X ng_,
类写好了,下面是在JSP中如下调用。 X-di^%<
ZyqTtA!A
<% JL1%XQ
i
CountBean cb=new CountBean();
z"BV+
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); rVkoj;[
CountCache.add(cb); |Iy55~hK`
out.print(CountCache.list.size()+"<br>"); S EY
CountControl c=new CountControl(); Fi{~UOZg
c.run(); 0|X!Uw-Q%_
out.print(CountCache.list.size()+"<br>"); 2tvMa%1^
%>