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: j7"E0Wc^o_
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CountBean.java #1m!,tC
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/* /0@}7+&
* CountData.java q+)KY
* ,QG,tf?
* Created on 2007年1月1日, 下午4:44 Z/Mp=273
* Za=<euc7
* To change this template, choose Tools | Options and locate the template under :Z1_;`>CT
* the Source Creation and Management node. Right-click the template and choose yd>kJk^~/
* Open. You can then make changes to the template in the Source Editor. Z\dILt:#z
*/ lzm9ClkfH
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package com.tot.count; )OjbmU!7
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/** K8e >sU.
* fI"`[cA"]
* @author CGv(dE,G&]
*/ [nG/>Z]W
public class CountBean { iW |]-Ba\
private String countType; Az0Yt31=
int countId; C5XCy%h
/** Creates a new instance of CountData */ M~
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public CountBean() {} hoU&'P8
public void setCountType(String countTypes){ 94K;=5h
this.countType=countTypes; (y(V,kXwa8
} TXrC5AJx
public void setCountId(int countIds){ ](8XC_-U'
this.countId=countIds; Uv%"45&7
} p8F|]6Z
public String getCountType(){ NPf,9c;
return countType; >@ EQarD
} _Zb_9&
public int getCountId(){ '| Ag,x[
return countId; 45ct*w
} P#EqeO
}
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CountCache.java @&h<jM{D
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/* * z{D}L-&
* CountCache.java S6]D;c8GE
* 's&Vg09D,
* Created on 2007年1月1日, 下午5:01 '*)!&4f
* U?>zq!C&R
* To change this template, choose Tools | Options and locate the template under V(w[`^I>~
* the Source Creation and Management node. Right-click the template and choose ^P{'l^CVX
* Open. You can then make changes to the template in the Source Editor. hXMC!~Th
*/ EaP#~x
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package com.tot.count; .cu5h
import java.util.*; 9N'$Y*. d<
/** CQv
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* -R&h?ec
* @author b_wb!_
*/ %lV>Nc|iz=
public class CountCache { .h7b 4J
public static LinkedList list=new LinkedList(); sav2 .w
/** Creates a new instance of CountCache */ CTPn'P=\C
public CountCache() {} );,#H`'
public static void add(CountBean cb){ fcV/co_S6
if(cb!=null){ [5m;L5
list.add(cb); ?*4]LuK6
} LO` (V
} ef,6>xv
} x/9`2X`~
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CountControl.java }8r+&e
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/* 9&2kuLp?P
* CountThread.java c6?5?_ne
* Gjv'$O2_
* Created on 2007年1月1日, 下午4:57 \Dt0
}
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* % yJs"%
* To change this template, choose Tools | Options and locate the template under ShSh/0
* the Source Creation and Management node. Right-click the template and choose x,p|n
* Open. You can then make changes to the template in the Source Editor. |
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*/ px-*uh<
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package com.tot.count; 071wo7
import tot.db.DBUtils; FPcgQ
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import java.sql.*; PE4{;|a }
/** [{Y$]3?}
* KNK0w 5
* @author ("{AY?{{
*/ $s)
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public class CountControl{ j" YJ1R-5
private static long lastExecuteTime=0;//上次更新时间 LW2Sko?Yo
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 ,xR^8G8
/** Creates a new instance of CountThread */ $*2uI?87}:
public CountControl() {} x#ouR+<
public synchronized void executeUpdate(){ Ebq5P$
Connection conn=null; ]-ZD;kOr
PreparedStatement ps=null; y:W$~<E`p
try{ bk>M4l61
conn = DBUtils.getConnection(); w5&UG/z%l
conn.setAutoCommit(false); q.g!WLiI
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); M8g=t[\
for(int i=0;i<CountCache.list.size();i++){ *XNvb ^<
CountBean cb=(CountBean)CountCache.list.getFirst(); c<4pu
CountCache.list.removeFirst(); v4qvqGK
ps.setInt(1, cb.getCountId()); ?rv+ydR/q
ps.executeUpdate();⑴ '!y ^
//ps.addBatch();⑵ }>h?W1
} >i=O =w
//int [] counts = ps.executeBatch();⑶ B!8]\D
conn.commit(); [[bMYD1eO
}catch(Exception e){ (jQL?
e.printStackTrace(); *Qyw
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} finally{ U+'?#"
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try{ vn
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if(ps!=null) { 8`^I.tD
ps.clearParameters(); X*8U%uF
ps.close(); ]jy6C'Mp
ps=null; QU417EV'
} 4y
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}catch(SQLException e){} !UgJ^v
DBUtils.closeConnection(conn); b$B5sKQ
} }}Q|O]e
} jh=:Q P/
public long getLast(){ }K&K{ 9}
return lastExecuteTime; ;Y)?6^"
} Z4t9q`}h
public void run(){ "E'OPR
long now = System.currentTimeMillis(); Xbap'/t
if ((now - lastExecuteTime) > executeSep) { <rCl
//System.out.print("lastExecuteTime:"+lastExecuteTime); YjsaTdZ!&
//System.out.print(" now:"+now+"\n"); _@d.wfM
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); !E$S&zVMQ
lastExecuteTime=now; 55yP.@i9J
executeUpdate(); ^@tn+'.
} ZegsV|
else{ H,\c"
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); X}?cAo2N
} op"Cc
} }uZhoA
} hL8QA!
//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 MiRMjQ2
^ ]`<nO
类写好了,下面是在JSP中如下调用。 qdcCX:Z<
d/* [t!
<% w0
"h,{
CountBean cb=new CountBean(); m&;
t;
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); >~ne(n4qy
CountCache.add(cb); j)J4[j
out.print(CountCache.list.size()+"<br>"); (]iw#m{
CountControl c=new CountControl(); h~F uuL
c.run(); l
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out.print(CountCache.list.size()+"<br>"); VF6@;5p
%>