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: m NUN6qVP~
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CountBean.java bqZ?uvc3
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/* Ff)~clIK '
* CountData.java H3
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* C$N4
* Created on 2007年1月1日, 下午4:44 '<RB
* V\iIvBpWg
* To change this template, choose Tools | Options and locate the template under q;1VF;<"vH
* the Source Creation and Management node. Right-click the template and choose oiTMP`Y
* Open. You can then make changes to the template in the Source Editor. ]>VJ--fH
*/ ~|aeKtCs(.
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package com.tot.count; "}]GQt< F
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/** d&[M8(
* *pcbwd!/
* @author ;55tf
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*/ ?L<UOv7;t
public class CountBean { vWnHC
private String countType; vOvxQS}dBp
int countId; &J5-'{U|0
/** Creates a new instance of CountData */ u7WTSL%
public CountBean() {} bWX[<rh'
public void setCountType(String countTypes){ k$UzBxR
this.countType=countTypes; Mm>zpB`qP
} +LQs.*
public void setCountId(int countIds){ :=iM$_tp'
this.countId=countIds; !T#8N7J>
} /ygUd8@
public String getCountType(){ SU_]C+
return countType; [T}%q"<
} %#S "~)
public int getCountId(){ @w#gRQCl
return countId; ijZydn
} + e5
} ]AFM Y<mB
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CountCache.java %U=S6<lbj;
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/* *oX
* CountCache.java Up/eV}C
* q/rHHuY}
* Created on 2007年1月1日, 下午5:01 # o;CmB
* 8ACYuN\
* To change this template, choose Tools | Options and locate the template under HdY3DdC%q
* the Source Creation and Management node. Right-click the template and choose 07T;IV3#C5
* Open. You can then make changes to the template in the Source Editor. uDy>xJ|
*/ "a0u-}/D
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package com.tot.count; f}9PEpa,Z
import java.util.*; H/^TXqQ8
/** lH,]ZA./
* XoH[MJC
* @author *Lb(urf
*/ <QkN}+B=
public class CountCache { V~]'+A
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public static LinkedList list=new LinkedList(); 6'No4[F
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/** Creates a new instance of CountCache */ T
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public CountCache() {} !F7EAQn{(
public static void add(CountBean cb){ s5zGg]0
if(cb!=null){ RIVL 0Ig
list.add(cb); [c
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} f)AW !/
} Il&"=LooZ
} 5uD#=/oV
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CountControl.java ?*z(1!
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/* "zeJ4f
* CountThread.java O=#/DM;
* &,Zz
* Created on 2007年1月1日, 下午4:57 -u3SsU)_%N
* ?ck^? p7
* To change this template, choose Tools | Options and locate the template under 1EAVMJ
* the Source Creation and Management node. Right-click the template and choose jy__Y=1}
* Open. You can then make changes to the template in the Source Editor. @E"+qPp.3
*/ FSYjp{z5
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package com.tot.count; %<ptkZK#
import tot.db.DBUtils; =-Q
import java.sql.*; %)6:eIS
/** zfr (dQ
* 3 R:7bex
* @author Qq FfR#
*/ g]@R'2:1
public class CountControl{ Cs1%g
private static long lastExecuteTime=0;//上次更新时间 ko+M,kjwR
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 a`@<Z sR
/** Creates a new instance of CountThread */ S]K6qY
public CountControl() {} X_tW#`
public synchronized void executeUpdate(){ 53u.pc
Connection conn=null; kq1M<lk
PreparedStatement ps=null; tEWj}rX
try{ N5w]2xz!
conn = DBUtils.getConnection(); R/Dy05nloe
conn.setAutoCommit(false); (g)lv)4P
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); G|PIH#
for(int i=0;i<CountCache.list.size();i++){ R0YC:rAt
CountBean cb=(CountBean)CountCache.list.getFirst(); Dho^^<`c+
CountCache.list.removeFirst(); P B6/<n9#
ps.setInt(1, cb.getCountId()); c@o/Cv
ps.executeUpdate();⑴ /P8eI3R
//ps.addBatch();⑵ EhP&L?EL
} Bn#HJ17/#
//int [] counts = ps.executeBatch();⑶ |E_+*1l q.
conn.commit(); r/q1&*T
}catch(Exception e){ cV,03]x
e.printStackTrace(); YZ%f7BUk
} finally{ fssL'DD
try{ P#2TM
if(ps!=null) { $OFFH[_z
ps.clearParameters(); 1:{O RX[;
ps.close(); jXDzjt94J
ps=null;
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} RJ@e5A6_
}catch(SQLException e){} n xh/&%
DBUtils.closeConnection(conn); G`9F.T_Z^)
} IrwF
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} h&)vdCCk
public long getLast(){ :jKXKY+T
return lastExecuteTime; #u=O 5%.
} M4hN#0("4
public void run(){ fN*4(yw
long now = System.currentTimeMillis(); ubC JZ"!
if ((now - lastExecuteTime) > executeSep) { k#=leu"I
//System.out.print("lastExecuteTime:"+lastExecuteTime); 7quwc'!
//System.out.print(" now:"+now+"\n"); r+#V{oE_
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); = cI\OsV&?
lastExecuteTime=now; Y`O}]*{>8R
executeUpdate(); 1\608~ZH
} k}0
else{ ={i&F
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); M"$RtS|h
} ]MA)='~
} bQN4ozSi
} f+*2K^B
//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 O"-PNF,J
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类写好了,下面是在JSP中如下调用。 &\]f!'jV
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<% zQ|x>3
CountBean cb=new CountBean(); ^nm!NL{z^
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); Boj{+rE0
CountCache.add(cb); owY_cDzrH
out.print(CountCache.list.size()+"<br>"); cSs/XJZ
CountControl c=new CountControl(); 0!'M#'m
c.run(); -JO46
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out.print(CountCache.list.size()+"<br>"); o(SJuZC/U
%>