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: ^
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CountBean.java qlUYu"`i
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/* v | /IN
* CountData.java M%7H-^{
* aE^tc'h~
* Created on 2007年1月1日, 下午4:44 QjfQoT F
* K[LTw_oE
* To change this template, choose Tools | Options and locate the template under U5mec167
* the Source Creation and Management node. Right-click the template and choose }I7/FqrD
* Open. You can then make changes to the template in the Source Editor. WG
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*/ WNTm
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package com.tot.count; ?r@euZ&
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/** f}bUuQrH-!
* amf=uysr
* @author V"VWHAu*.w
*/ 3nBbPP_
public class CountBean { r
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private String countType; /qF7^9LtaY
int countId; okX\z[X
/** Creates a new instance of CountData */ U'LO;s04m
public CountBean() {} A"Rzn1/
public void setCountType(String countTypes){ uVqJl{e\
this.countType=countTypes; uAyj##H
} uMF\3T(x4
public void setCountId(int countIds){ +7<{yP6wU
this.countId=countIds; W0$G7s
} PK C``+Ki
public String getCountType(){ q9qmz[
return countType; kETA3(h'
} #RJy
public int getCountId(){ '2]u{rr~+
return countId; }M/w 0U0o
} &tZ?%sr
} 0[D5]mcv
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CountCache.java GT%V,OJ
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/* aEdFZ
* CountCache.java 5 LX3.
* @.*[CC;&
* Created on 2007年1月1日, 下午5:01 >^:g[6Sj
* ,@='.Qs4g
* To change this template, choose Tools | Options and locate the template under ~N[hY1}X[
* the Source Creation and Management node. Right-click the template and choose t@.gmUUA
* Open. You can then make changes to the template in the Source Editor. LO.4sO
*/ h9+ylHW_cp
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package com.tot.count; +nuv?QB/
import java.util.*; 94APjqV6'
/** 8tA.d.8
* (%#d._j>fZ
* @author N/{A'
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*/ 77i |a]Kd
public class CountCache { $%r|V*5
public static LinkedList list=new LinkedList();
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/** Creates a new instance of CountCache */ #j-,#P@
public CountCache() {} ,zXL8T
public static void add(CountBean cb){ a
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if(cb!=null){ ZX'{o9+w5
list.add(cb); $:u,6|QsS=
} ]Vb#(2<2
} 5.?O PK6
} ,;+\!'lS
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CountControl.java 8~HC0o\2
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/* {Y/|7Cl0
* CountThread.java v9inBBC q
* ;g*X.d
* Created on 2007年1月1日, 下午4:57 tMAa$XrZj
*
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* To change this template, choose Tools | Options and locate the template under yFpHRfF}
* the Source Creation and Management node. Right-click the template and choose ,o9)ohw
* Open. You can then make changes to the template in the Source Editor. s=%HT fw
*/ i[\[xfk
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package com.tot.count; raqLXO!j
import tot.db.DBUtils; :W1,s53
import java.sql.*; 0'py7
/** \^#1~Kx
* DGd&x^C
* @author L//sJe
*/ 5ef&Ih.3
public class CountControl{ ;~1r{kXxA"
private static long lastExecuteTime=0;//上次更新时间 ^1~/FU
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 6\TstY3
/** Creates a new instance of CountThread */ 'nT#3/rL
public CountControl() {} Q?"[zX1
public synchronized void executeUpdate(){ Q5<vK{
Connection conn=null; &)X<yd0
PreparedStatement ps=null; -:~`g*3#
try{ L}21[ N~ky
conn = DBUtils.getConnection(); i*^K)SI8
conn.setAutoCommit(false); cbwzT0
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); ~qqtFjlG^
for(int i=0;i<CountCache.list.size();i++){ _yoG<qI
CountBean cb=(CountBean)CountCache.list.getFirst(); 1|nB\xgu
CountCache.list.removeFirst(); <>e<Xd:77{
ps.setInt(1, cb.getCountId()); @ [FFYVru
ps.executeUpdate();⑴ >bZ#
//ps.addBatch();⑵ U3V<ITZI8t
} xg^fM@#m
//int [] counts = ps.executeBatch();⑶ kdHql>0
conn.commit(); :5*<QJuI#A
}catch(Exception e){ )F$Stg3e
e.printStackTrace(); L_.}z)S[\
} finally{ p!a%*LfND
try{ <+b:
if(ps!=null) { F0JFx$AoD
ps.clearParameters(); ?hmb"^vlG
ps.close(); ,9pi9\S
ps=null; kp6x6%{K\
} &q<8tTW5
}catch(SQLException e){} {Psj#.qP1
DBUtils.closeConnection(conn); -J30g\
} 5`uS<[vA
} p)jxqg
public long getLast(){ q
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return lastExecuteTime; sWC"^ S o
} u l%bo%&~
public void run(){ #TWc` 8
long now = System.currentTimeMillis(); A;!FtD/
if ((now - lastExecuteTime) > executeSep) { sZH7EK
//System.out.print("lastExecuteTime:"+lastExecuteTime); q"Md)?5N
//System.out.print(" now:"+now+"\n"); %:,=J
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); aOHCr>po,
lastExecuteTime=now; x-pMT3m\D#
executeUpdate(); qck/b
} U %ESuq#
else{ DPwSg\*)
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); PWMaB
} 9CNHjs+-}s
} l(5-Cr
} 5);#\&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 Wj:QC<5
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类写好了,下面是在JSP中如下调用。 ;Kf|a}m -
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<% C6VoOT)\
CountBean cb=new CountBean(); g5Dx9d{
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); Q
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CountCache.add(cb); W/>?1+r.Z
out.print(CountCache.list.size()+"<br>"); gQuw|u
CountControl c=new CountControl(); i .N1Cvp&
c.run(); 4l''/$P
out.print(CountCache.list.size()+"<br>"); Nd_@J&
%>