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: iVM{ L
h(hb?f@1:
CountBean.java `;L0ax
W?m?r.K?
/* fL7ym,?
* CountData.java ZFy>Z:&S,
* iY~9`Q1E
* Created on 2007年1月1日, 下午4:44 |9)Q =(
* 'vO+,-
* To change this template, choose Tools | Options and locate the template under hia_CuY#
* the Source Creation and Management node. Right-click the template and choose /#?lG`'1
* Open. You can then make changes to the template in the Source Editor. QKYGeT7&Y'
*/ 9k_3=KS3N
euHX7
package com.tot.count; }}v04~
P%5h!Z2m
/** p1p4t40<l
* ;ti{
#(Ux
* @author WY%LeC!t
*/ M>df7.N7%P
public class CountBean { c?L_n=B
private String countType; rm*Jo|eH`
int countId; G0Wzx)3]
/** Creates a new instance of CountData */ _p vL b
public CountBean() {} _s./^B_w!
public void setCountType(String countTypes){ $smzP.V
this.countType=countTypes; &$fe%1#
} F"9f6<ge
public void setCountId(int countIds){ )J+vmY~&
this.countId=countIds; SGMLs'D
} 5gWn{[[e)y
public String getCountType(){ =:(8F*Q
return countType; 8Z>ZjNG
} @p jah(i`
public int getCountId(){ 5H#3PZaQ
return countId; b'fj
} Y418k
} eRllF `*
,R$n I*mf_
CountCache.java F|X-|Co
>lqWni
/* v/f&rK* >
* CountCache.java d[z+/L
* z#b31;A@$
* Created on 2007年1月1日, 下午5:01 _Tyj4t0ElV
* 8"+Re
[
* To change this template, choose Tools | Options and locate the template under 6o&{~SV3
* the Source Creation and Management node. Right-click the template and choose FA\gz?h
* Open. You can then make changes to the template in the Source Editor. 9PEjV$0E2
*/ krm&.J
Y;>0)eP
package com.tot.count; )K\w0sjR
import java.util.*; =
wNul"
/** eHG**@"X
* a
1bu
* @author J?$4Yf
*/ O&]Y.Z9,A
public class CountCache { 1tG,V%iCp
public static LinkedList list=new LinkedList(); <#ujm fD
/** Creates a new instance of CountCache */ %(b`i C9
public CountCache() {} r7sPFM
public static void add(CountBean cb){ Nzz" w_#
if(cb!=null){ ?lCKZm.,(-
list.add(cb); (
3IM7
} 6l IFxc
} s]0x^"#B
} 0Ph,E
4O[T:9mn0
CountControl.java 5B| iBS l
Gs2.}lz
/* Mq]~Ka3q7
* CountThread.java nK Rx_D$d
* yB(^t`)}N
* Created on 2007年1月1日, 下午4:57 ]c8lZO>
* 0Z#&!xTb
* To change this template, choose Tools | Options and locate the template under
(`gqLPx[
* the Source Creation and Management node. Right-click the template and choose ;ej;<7+
* Open. You can then make changes to the template in the Source Editor. vBQ|h
*/ :*TfGV
h,<%cvU=
package com.tot.count; iNf+ -C3
import tot.db.DBUtils; P5Ms
X~mT
import java.sql.*; a;m-Vu!
/** &| el8;D
* `p9h$d
* @author d}%GHvOi
*/ m6Q lIdl
public class CountControl{ yL&F!+(/Ix
private static long lastExecuteTime=0;//上次更新时间 ? e%Pvy<i
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 ZVE q{x1Zc
/** Creates a new instance of CountThread */ ]1rr$f9
public CountControl() {} RUm1;MWs
public synchronized void executeUpdate(){ 9)s=%dL
Connection conn=null; MsCY5g
PreparedStatement ps=null; 31k.{dnm
try{ C/ow{MxA
conn = DBUtils.getConnection(); %v:9_nwO)
conn.setAutoCommit(false); |"DQ^)3Pi
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); Q u2W
for(int i=0;i<CountCache.list.size();i++){ 21M@z(q*
CountBean cb=(CountBean)CountCache.list.getFirst(); /og2+!
CountCache.list.removeFirst(); $@[6j y
ps.setInt(1, cb.getCountId()); azz6_qk8
ps.executeUpdate();⑴ #
9Z];<g
//ps.addBatch();⑵ ( du<0J|PT
} D_`MeqF}C
//int [] counts = ps.executeBatch();⑶ tlu-zUsi
conn.commit(); PoY+Y3
}catch(Exception e){ >F6'^9|
e.printStackTrace(); e?3 S0}
} finally{ D#508{)
try{ $/nU0W
if(ps!=null) { W"YFx*W
ps.clearParameters(); uG&xtN8
ps.close(); eiI}:5~
/g
ps=null; #A@*k}/+
} "n:z("Q*
}catch(SQLException e){} >}GtmnF
DBUtils.closeConnection(conn); LHKawEZ
} wgpu]ooUF&
} QM`A74j0]\
public long getLast(){ T?:Vw laE
return lastExecuteTime; "zL<:TQ"
} <i`Ipj
public void run(){ &,2XrXiFu
long now = System.currentTimeMillis(); 0Pu$1Fp
if ((now - lastExecuteTime) > executeSep) { 3D[IZ^%VtM
//System.out.print("lastExecuteTime:"+lastExecuteTime); [2~Et+r6g
//System.out.print(" now:"+now+"\n"); 8v\BW^z3
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); xRq|W4ay
lastExecuteTime=now; B<J}YN
executeUpdate(); ZJ'#XZpr
} Eic/#j{4
else{ ko*Ir@SDv
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); U-#wFc2N
} I0.{OJ-
} SaMg)s~B
} Ly/"da
//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 nJY#d;
7"wr8
类写好了,下面是在JSP中如下调用。 y|Tb&XPD
:w:hqe|_
<% Ey A}
CountBean cb=new CountBean(); uj,YCJ8UZs
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); *KN ' 0Z@W
CountCache.add(cb); ZGf R:a)wc
out.print(CountCache.list.size()+"<br>"); 3|8\,fO?
CountControl c=new CountControl(); Z\D!'FX
c.run(); LJ`*&J
out.print(CountCache.list.size()+"<br>"); R2yiExw<
%>