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: lJ] \
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CountBean.java /xm#:+Sc
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/* ,{ L;B
* CountData.java qwNKRqT
* LXu"rfp
* Created on 2007年1月1日, 下午4:44 E,D:D3O
* ;ko[(eFN@
* To change this template, choose Tools | Options and locate the template under xAd>",=~
* the Source Creation and Management node. Right-click the template and choose BXK::M+
* Open. You can then make changes to the template in the Source Editor. fByh";<`P
*/ /$Tl#
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package com.tot.count; <X I35\^
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/** ic0v*Y$
* 'f?&EsIV?
* @author n@07$lY@;
*/ R|)2Dg
public class CountBean { _[{:!?-?
private String countType; 97]a-)SA
int countId; 4j/ iG\
/** Creates a new instance of CountData */ qv0
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public CountBean() {} w^dueP7J
public void setCountType(String countTypes){ qzHqj;
this.countType=countTypes; Z?~d']XD
} 4I#eC#"
public void setCountId(int countIds){ C>:/(O
this.countId=countIds; $nfBvf
} (+gL#/u
public String getCountType(){
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return countType; 8G5)o`
} pg?i F1
public int getCountId(){ N,/BudFo
return countId; AJ#m6`M+EK
} jI{~s]Q
} iO9nvM<
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CountCache.java da00p-U
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/* ^)hAVf~E
* CountCache.java kh<pLI >$h
* $/, BJ/9
* Created on 2007年1月1日, 下午5:01 UKKSc>D1
* O/DAf|X|
* To change this template, choose Tools | Options and locate the template under EREolCASb
* the Source Creation and Management node. Right-click the template and choose %K%^ ]{
* Open. You can then make changes to the template in the Source Editor. $*AC>i\
*/ (@KoqwVWc
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package com.tot.count; @q> ktE_
import java.util.*; (Pk"NEP
/** Q5p+ W
* 2/v35| ?
* @author =mHkXHE~:
*/ *t#s$Ga
public class CountCache { zd*3R+>U'>
public static LinkedList list=new LinkedList(); k'[ S@+5
/** Creates a new instance of CountCache */ HDF!`
public CountCache() {} :M22P`:
public static void add(CountBean cb){ Sc1+(z
if(cb!=null){ k]SAJ~bS|
list.add(cb); Dd!Sr8L[
} %s$rP
} 2E`~ qn
} <i_>
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CountControl.java .e`,{G(5q7
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/* <91t`&aWW
* CountThread.java NXzU0
* O^.%C`*
* Created on 2007年1月1日, 下午4:57 *:=];1O
* v!NB~"LQ
* To change this template, choose Tools | Options and locate the template under ^ckj3Y#;
* the Source Creation and Management node. Right-click the template and choose nE/=:{~Ws
* Open. You can then make changes to the template in the Source Editor. Dh2:2Rz=#7
*/ S5i+vUI8C
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package com.tot.count; &EAk
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import tot.db.DBUtils; z 0~j
import java.sql.*; \\=.6cg<K
/** cu[!D}tVU
* >f&xJq
* @author F\>oxttS1
*/ ^C!mCTL1N
public class CountControl{ :e1'o
private static long lastExecuteTime=0;//上次更新时间 x!'7yx
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 mJ)tHv"7
/** Creates a new instance of CountThread */ B{s]juPG
public CountControl() {} ]]>nbgGn#
public synchronized void executeUpdate(){ yZq?B
Connection conn=null; xT W3UY
PreparedStatement ps=null; %$Aqbd
try{ $bk>kbl P
conn = DBUtils.getConnection(); jvu
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conn.setAutoCommit(false); S[vRw]*
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); IuNkfBe4m
for(int i=0;i<CountCache.list.size();i++){ HtxLMzgz<<
CountBean cb=(CountBean)CountCache.list.getFirst(); *5e<\{!
CountCache.list.removeFirst(); 5N\+@grp
ps.setInt(1, cb.getCountId()); :]'q#$!
ps.executeUpdate();⑴ Q~phGD3!~
//ps.addBatch();⑵ +9RJ%i&Ec
} Bb~5& @M|N
//int [] counts = ps.executeBatch();⑶ |V lMmaz
conn.commit(); z; J
}catch(Exception e){ 9hy'DcSy,
e.printStackTrace(); [q'eENG
} finally{ s}wO7Df=+
try{ J==}QEhQ{
if(ps!=null) { 3c b[RQf
ps.clearParameters(); F#su5<d
ps.close(); ' PELf
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ps=null; ;d4y{
} ,(P %z.P@
}catch(SQLException e){} 7{-@}j`
DBUtils.closeConnection(conn); V7:\q^$
} Q\|18wkW
} [UoqIU
public long getLast(){ `$at9
return lastExecuteTime; G;NB\3~X
} g92dw<$>
public void run(){ #7o0dE;Kg9
long now = System.currentTimeMillis(); (k8Z=/N~
if ((now - lastExecuteTime) > executeSep) { fWj@e"G
//System.out.print("lastExecuteTime:"+lastExecuteTime); :9`qogF>
//System.out.print(" now:"+now+"\n"); )A"jVQjI%w
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); 9\AS@SH{^T
lastExecuteTime=now; ugI#ZFjJWE
executeUpdate();
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} jB!W2~Z
else{ .a:Z!KF
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); Pu..NPl+
} Ir27ZP
} _dr*`yXi
} _s*!
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//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 D^u\l
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类写好了,下面是在JSP中如下调用。 <(YF5Xm6$h
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<% j;iL&eo>
CountBean cb=new CountBean(); oIb)
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cb.setCountId(Integer.parseInt(request.getParameter("cid"))); b+Vi3V
CountCache.add(cb); J)*8|E9P
out.print(CountCache.list.size()+"<br>"); j&CZ=?K^c
CountControl c=new CountControl(); c4 5?St
c.run(); (B:uc_+
out.print(CountCache.list.size()+"<br>"); .!yq@Q|=u
%>