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-qAI&V
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CountBean.java Qs
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/* %a
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* CountData.java %LP4RZ
* , +J)`+pJx
* Created on 2007年1月1日, 下午4:44 MnqT?Cc4$j
* A03io8D6
* To change this template, choose Tools | Options and locate the template under dWiNe!oY2
* the Source Creation and Management node. Right-click the template and choose P ?f${t+
* Open. You can then make changes to the template in the Source Editor. hBnUpYec
*/ F"k`PF*b
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package com.tot.count; i6k6l%
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/** lSaX!${R'T
* yc?L
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* @author #J3o~,t<
*/ \P+^BG!
public class CountBean {
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private String countType; $%\6"P/64
int countId; qMVuFwPhi
/** Creates a new instance of CountData */ !;(Wm6~*ad
public CountBean() {} h[iO'Vq
public void setCountType(String countTypes){ kN1R8| pv
this.countType=countTypes; "*D9.LyM
} FCEmg0qdjD
public void setCountId(int countIds){ "Y L^j~A
this.countId=countIds; t?-a JU
} r'#!w3*Cy
public String getCountType(){
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return countType; JD0s0>q_
} %V]v,
public int getCountId(){ h M7 SGEV
return countId; L5 Cfa-
} i"iy 0?
} K/Yeh<_&
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CountCache.java R|8L'H+1x
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/* (0Br`%!F
* CountCache.java )#M$ov
* Uv>e :U7 ;
* Created on 2007年1月1日, 下午5:01 %i3[x.M
* %.f%Q?P
* To change this template, choose Tools | Options and locate the template under X$\CC18
* the Source Creation and Management node. Right-click the template and choose mxF+Fp~
* Open. You can then make changes to the template in the Source Editor. J5Zz*'av'
*/ %G2g
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package com.tot.count; DFQ`(1Q
import java.util.*; <";1[A%7<
/** w (RRu~J
* TO5y.M|7
* @author HAI)+J
*/ %vy,A*
public class CountCache { Gr&e]M[ l
public static LinkedList list=new LinkedList(); de2G"'F
/** Creates a new instance of CountCache */ fi>.X99(G
public CountCache() {} &x\)] i2f
public static void add(CountBean cb){ 'D`lVUB
if(cb!=null){ qGV(p}$O
list.add(cb); &l]F&-
} +u=VO#IA#
} QOUyD;0IW
} !2HF|x$
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CountControl.java BC_<1
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/* }]dzY(
* CountThread.java 1+-Go}I
* *q=\e 9
* Created on 2007年1月1日, 下午4:57 7J5jf231
* eDP&W$s#
* To change this template, choose Tools | Options and locate the template under n=JV*h0
* the Source Creation and Management node. Right-click the template and choose kG5+kwV=:
* Open. You can then make changes to the template in the Source Editor. Ru#pJb(R
*/ tzd!r7
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package com.tot.count; c-&Q_lB
import tot.db.DBUtils; W&cs&>F#
import java.sql.*; $eT[`r
/** ./3/3&6
* PPV T2;9
* @author *2-b&PQR{
*/ 8$]SvfX
public class CountControl{ _u6NaB
private static long lastExecuteTime=0;//上次更新时间 G$'UK
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 9]ZfSn)
/** Creates a new instance of CountThread */ (-0d@eqw
public CountControl() {} h(AL\9{=}
public synchronized void executeUpdate(){ YU6|/
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Connection conn=null; `u_MdB}<x;
PreparedStatement ps=null; zQ,M795@EA
try{ I>l^lv&[+
conn = DBUtils.getConnection(); X,G"#j^
conn.setAutoCommit(false); n+&8Uk
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); P(I%9
for(int i=0;i<CountCache.list.size();i++){ _i7yyt;h
CountBean cb=(CountBean)CountCache.list.getFirst(); ji4bz#/B0
CountCache.list.removeFirst(); lY@2$q9BT
ps.setInt(1, cb.getCountId()); |ITCw$T
ps.executeUpdate();⑴ ^Tj{}<yT
//ps.addBatch();⑵ 4zhh**]B
} :%AEwRZ
//int [] counts = ps.executeBatch();⑶ C:sgT6
conn.commit(); %wru)
}catch(Exception e){ .
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e.printStackTrace(); NpM;vO
} finally{ tMP"9JE,
try{ Oh10X.)i
if(ps!=null) { -&1P2m/46
ps.clearParameters(); YR/I<m`]}
ps.close(); QX}JQ<8
ps=null; (U$;0`
} /%7&De6Xg
}catch(SQLException e){} 7D>_<)%d=
DBUtils.closeConnection(conn); s{7bu|0
} P"}"q ![
} ]G8"\J4 &
public long getLast(){ F?FfRzZ[
return lastExecuteTime; EQpF:@_
} <VstnJo`Z
public void run(){ ~&<vAgy,
long now = System.currentTimeMillis(); Crj7n/mp]s
if ((now - lastExecuteTime) > executeSep) { Mr4,?Z&`-d
//System.out.print("lastExecuteTime:"+lastExecuteTime); = vF!
//System.out.print(" now:"+now+"\n"); |Bi7:w
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); h$9ut@I
lastExecuteTime=now; *fj]L?,
executeUpdate(); 60ciI,_`
} m}D;=>2$
else{ Q;z!]hjBM
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); RS&BS;
} Vh=U/{Rp1
} Ylu\]pr9|C
} 8BZ&-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 xj8z*fC;
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类写好了,下面是在JSP中如下调用。 `s+kYWg'Z
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<% Z;1r=p#s
CountBean cb=new CountBean(); f<rn't{
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); 9Qu(RbDqC
CountCache.add(cb); =<PEvIn
out.print(CountCache.list.size()+"<br>"); stW
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CountControl c=new CountControl(); s~>1TxJe
c.run(); aqK+ u.H
out.print(CountCache.list.size()+"<br>"); #UwX~
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