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: ,sSo\%
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CountBean.java ! (lF#MG}
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/* 7WH'GoBh
* CountData.java 'qEw]l
* w_>\Yd [
* Created on 2007年1月1日, 下午4:44 r'nPP6`
* pf'DbY!
* To change this template, choose Tools | Options and locate the template under -zYa@PW
* the Source Creation and Management node. Right-click the template and choose 423%K$710
* Open. You can then make changes to the template in the Source Editor. cvy
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*/ LhKbZoPp
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package com.tot.count; 00D.Jn
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/** Cxq|N]E
* 68GH$ji
* @author '*XIp:
*/
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public class CountBean { U}:+Hz9
private String countType; 93D}0kp
int countId; 5JaLE5-
/** Creates a new instance of CountData */ DqY"N]
public CountBean() {} 2He R1m<
public void setCountType(String countTypes){ Hd;NvNS
this.countType=countTypes; 9c4p9b!
} >lM/\HO2
public void setCountId(int countIds){ U"|1@W#
this.countId=countIds; =D0d+b6
} M
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public String getCountType(){ m$W2E.-$'#
return countType; zQ:nL*X'Z"
} zmZU"eWp)
public int getCountId(){ p:b{>lM
return countId; Z] r9lC
} +JG05h%'
} WFc4(Kl
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CountCache.java \nP79F0%2
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/* (rJ-S"^u
* CountCache.java yuC$S&Y>!
* 6d8)]
* Created on 2007年1月1日, 下午5:01 bxPa|s?
* KM)MUPr
* To change this template, choose Tools | Options and locate the template under cXt&k
* the Source Creation and Management node. Right-click the template and choose |1
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* Open. You can then make changes to the template in the Source Editor. J
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*/ 8IL5:7H8
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package com.tot.count; :9L}jz
import java.util.*; yqK_|7I+
/** $X:,Q,?
* m;"[b (u
* @author `K0.6i [p
*/ U) xeta+
public class CountCache { %!-t7K^mFq
public static LinkedList list=new LinkedList(); k>MXOUaW.
/** Creates a new instance of CountCache */ w(_:+-rqQ<
public CountCache() {} L-U4
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public static void add(CountBean cb){ p`&{NR3+
if(cb!=null){ ?>ZrdfTwz,
list.add(cb); c8]%,26.
} h*KDZ+{)
} ik?IC$*n3i
} .e5@9G.jb
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CountControl.java BQUYT/$(
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/* jxW/"Q
* CountThread.java xS/=9l/G
* X`&Us
* Created on 2007年1月1日, 下午4:57 n::i$ZUdK
* =;n>#<
* To change this template, choose Tools | Options and locate the template under `_/1zL[
* the Source Creation and Management node. Right-click the template and choose _"D J|j
* Open. You can then make changes to the template in the Source Editor. }Gb^%1%M
*/ 1$# r)S[*
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package com.tot.count; PDc4ok`)
import tot.db.DBUtils; VIGLl'8p
import java.sql.*; =&-.] |t
/** aVVE2:M
* gjK: a@{
* @author
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*/ NI:OL
public class CountControl{ | 9 *$6Y
private static long lastExecuteTime=0;//上次更新时间 D5@}L$u
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 |@b|Q,
/** Creates a new instance of CountThread */ ?vD<_5K;I
public CountControl() {} d_:tiHw$
public synchronized void executeUpdate(){ 4E!Pxjl 3a
Connection conn=null; >~_>.R+{
PreparedStatement ps=null; /;Cx|\
try{ V^D1:9i
conn = DBUtils.getConnection(); #0*I|gfV
conn.setAutoCommit(false); n|=yw6aV'
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); b!SIs*
for(int i=0;i<CountCache.list.size();i++){ V^.Z&7+E`_
CountBean cb=(CountBean)CountCache.list.getFirst(); 2&s(:=
CountCache.list.removeFirst(); j _E(h.
ps.setInt(1, cb.getCountId()); |C+
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ps.executeUpdate();⑴ KVoi>?a
//ps.addBatch();⑵ )i39'0a
} <;+QK=f
//int [] counts = ps.executeBatch();⑶ Lrx"Hn{
conn.commit(); |M<R{Tt}nf
}catch(Exception e){ }
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e.printStackTrace(); ou|3%&*"
} finally{ b1e)w?n
try{ :/Y4I)'
if(ps!=null) {
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ps.clearParameters(); Q3)[
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ps.close(); E9 #o0Di
ps=null; I[ZWOi\-
;
} hoPh#? G
}catch(SQLException e){} $:DL+E-}
DBUtils.closeConnection(conn); 0B`rTLwB
} _#P5j#
} aC'#H8e|j
public long getLast(){ CS"k0V44}
return lastExecuteTime; .d)H2X
} wE <PXBl\b
public void run(){ M@.?l=1X
long now = System.currentTimeMillis(); :e_yOT}}
if ((now - lastExecuteTime) > executeSep) { T5-'|+
//System.out.print("lastExecuteTime:"+lastExecuteTime); ).C>>1ZC
//System.out.print(" now:"+now+"\n"); p_3VFKq>0
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); 5bK:sht
lastExecuteTime=now; a5g1.6hF
executeUpdate(); sD XJXJZ
} X.)1>zk
else{ #>$w9}gFi
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); =U~\iJ
} vs.}Bou]
} LrV4^{9(
} V SH64
//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 FRE${~Xd
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类写好了,下面是在JSP中如下调用。 c*>SZ'T\
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<% 6^p>f:5
CountBean cb=new CountBean(); 3o__tU)B
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); ##NowO
CountCache.add(cb); O~#OVFJ9=
out.print(CountCache.list.size()+"<br>"); 5U l=Nv]
CountControl c=new CountControl(); 9c@\-Z'
c.run(); f9E.X\"
out.print(CountCache.list.size()+"<br>"); bzMs\rj\
%>