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: +Z<Q^5w@
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CountBean.java x0h3jw+6
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/* )c >B23D
* CountData.java <ii1nz
* E5BgQ5'
* Created on 2007年1月1日, 下午4:44 'b?.\Bm;
* <N=p:e,aN,
* To change this template, choose Tools | Options and locate the template under q[OTaSQ~u^
* the Source Creation and Management node. Right-click the template and choose .7gE^
* Open. You can then make changes to the template in the Source Editor. Qb't*2c%
*/ r82o[+$u0K
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package com.tot.count; UnWGMo?JEi
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/** 1 j^c
* -A%?T"
* @author H'GYJ ?U"
*/ k\#-6evT
public class CountBean { .83v~{n
private String countType; -y*_.Ws9
int countId; `$sY^EX
/** Creates a new instance of CountData */ 1H4Zgh
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public CountBean() {} /3[9{r
public void setCountType(String countTypes){ 42>m,fb2[
this.countType=countTypes; Fv);5LD
} ^_KD&%M6
public void setCountId(int countIds){ bxdXZBn
this.countId=countIds; iE^a%|?}
} !ObE{2Enf
public String getCountType(){ zYG,x*IH
return countType; "8muMa8Q%
} IiK(^:~%
public int getCountId(){ Lcs{OW,
return countId; \FoxKOTp
} ,#bb8+z&p
} 4iv]N 4
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CountCache.java !b]2q%XM
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/* jfY{z=*]u
* CountCache.java OOBcJC
* .K@x4
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* Created on 2007年1月1日, 下午5:01 q#(/*AoU
* HD:%Yv
* To change this template, choose Tools | Options and locate the template under |N$?_<H
* the Source Creation and Management node. Right-click the template and choose <P^hYj-swh
* Open. You can then make changes to the template in the Source Editor. mheU#&|
*/ 1n`1o-&l-
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package com.tot.count; q^N0abzgP
import java.util.*; ;sChxQ=.^
/** SCurO9RN
* WR
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* @author Itr7lv'5xx
*/ e*P=2*]M
public class CountCache { A} -&C
public static LinkedList list=new LinkedList(); \POnsM)+l
/** Creates a new instance of CountCache */ \|~?x#aA
public CountCache() {} ^b"bRQqm
public static void add(CountBean cb){ 1O9p YW5J
if(cb!=null){ q qe2,X?
list.add(cb); o3F|#op
} ``|gcG
} o'eI(@{F=
} G;Wkm|
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CountControl.java EDHg'q
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/* !eR-Kor
* CountThread.java g %\$ !b
* }(ma__Ao
* Created on 2007年1月1日, 下午4:57 0F+zG)G"
* W`N}
* To change this template, choose Tools | Options and locate the template under W]O@DS zR
* the Source Creation and Management node. Right-click the template and choose wHtJ_Y
* Open. You can then make changes to the template in the Source Editor. Zlk,])9 Q
*/ zkh hN"bX
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package com.tot.count; oQ%\[s$
import tot.db.DBUtils; g8I!E$
import java.sql.*; *qPdZ
/** M?Ndy*]
* qx2E-PDL;<
* @author |.(CIu~b
*/ W-z90k4Z5
public class CountControl{ i,#k}CNu
private static long lastExecuteTime=0;//上次更新时间 q]eFd6
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 [0&'cu>
/** Creates a new instance of CountThread */ M@~~f
public CountControl() {} Dn_"B0$lk
public synchronized void executeUpdate(){ 2~!R*i
Connection conn=null; R<;OEN
PreparedStatement ps=null; x6^l6 N
try{ tlV &eN
conn = DBUtils.getConnection(); D0/DI
conn.setAutoCommit(false); veUa|Bx.(v
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); J3e:Y!
for(int i=0;i<CountCache.list.size();i++){ /2;dH]o0
CountBean cb=(CountBean)CountCache.list.getFirst(); E dn[cH7
CountCache.list.removeFirst(); yB,{#nM>8
ps.setInt(1, cb.getCountId()); FxCZRo&
ps.executeUpdate();⑴ 7v_i>_m]
//ps.addBatch();⑵ JiFA]M`^Q
} ebN(05ZV
//int [] counts = ps.executeBatch();⑶ wjTNO0hj
conn.commit(); :zdEq")v
}catch(Exception e){ 2W^B{ZS;
e.printStackTrace(); u5w&X8x
} finally{ jzs.+dAg
try{ IKi{Xh]\
if(ps!=null) { 9u,8q:I.?
ps.clearParameters(); KVB0IXZC~
ps.close(); w66v\x~
ps=null; u8YB)kG
} E6Q]A~
}catch(SQLException e){} A8pj~I/*-
DBUtils.closeConnection(conn); T[;;9z
} 1 -ZJT
} i;o}o*=
public long getLast(){ I^~=,D
return lastExecuteTime; l|YT[LR7
} $. %L
public void run(){ LY]nl3{E
long now = System.currentTimeMillis(); 'K@-Z]
if ((now - lastExecuteTime) > executeSep) { TUh&d5a9H
//System.out.print("lastExecuteTime:"+lastExecuteTime); ]^=|Zd-
//System.out.print(" now:"+now+"\n"); qib7Z]j
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); 6HoqEku/Q
lastExecuteTime=now; [X,A'Q
executeUpdate(); AR%hf
} "8 N"Udu
else{ TQP+>nS,
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); XZS5B~E
'
} 8|O=/m ^]
} N&T:Lt_N
} yN*:.al
//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=pt_!i/
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类写好了,下面是在JSP中如下调用。 <i{K7}':
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<% !;%y$$gxh
CountBean cb=new CountBean(); &lAQ &
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); wGvhB%8K
CountCache.add(cb); zJ9v%.e
out.print(CountCache.list.size()+"<br>"); dUS ZNY
CountControl c=new CountControl(); )QmGsU}?
c.run(); h#i\iK&A
out.print(CountCache.list.size()+"<br>"); >':5?\C+-
%>