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: wMN]~|z>
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CountBean.java *LY8D<:zs
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/* \~ wMfP8
* CountData.java $ ocdI5
* 9lE_nc
* Created on 2007年1月1日, 下午4:44 >yDZw!C
* />>\IR
* To change this template, choose Tools | Options and locate the template under _)-o1`*-
* the Source Creation and Management node. Right-click the template and choose \fe]c :
* Open. You can then make changes to the template in the Source Editor. q5S9C%b
*/ q@2siI~W
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package com.tot.count; I%Z
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/**
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* TD_Oo-+\
* @author *Pg2c(Vg
*/ ySI!d|_
public class CountBean { /qw.p#
private String countType; PPsE${!
int countId; \l3h0R
/** Creates a new instance of CountData */ vZ Lf
public CountBean() {} "kF g
public void setCountType(String countTypes){ e96k{C`j0
this.countType=countTypes; &cTU
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} FVBYo%Ap
public void setCountId(int countIds){ x,V r=FB
this.countId=countIds; 2J;g{95z
} *8XEYZa
public String getCountType(){ @KAI4LP
return countType; Kc(FX%3LU
} 3;Fhg!ZO
public int getCountId(){ :BTq!>s
return countId; 9nbLg5P
} TS5Q1+hWHV
} &kw@,];4Z
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CountCache.java ehY5!D1Q
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/* :Ux_qB
* CountCache.java HpnWoDM
* 8~gLqh8^V
* Created on 2007年1月1日, 下午5:01 "zy7C*)>r
* #LOwGJ$yVz
* To change this template, choose Tools | Options and locate the template under 8\gjST*
* the Source Creation and Management node. Right-click the template and choose v.5+7,4
* Open. You can then make changes to the template in the Source Editor. )dSi/
*/ 4X|zmr:A
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package com.tot.count; :\U{_@?`%
import java.util.*; g=o4Q<
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/** po7q mLq
* @s^-.z
* @author #3d(M
*/ o _H`o&xr
public class CountCache { @\I#^X5lv
public static LinkedList list=new LinkedList(); pb=h/8R
/** Creates a new instance of CountCache */ \uMLY<]P
public CountCache() {} N}YkMJy
public static void add(CountBean cb){ TuqH*{NNy9
if(cb!=null){ gPc=2
list.add(cb); t&DEb_"De
} Ti&z1_u
} 8HdAFRw
} `@|$,2[C
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CountControl.java C"enpc_C/
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/* WMP,\=6k0
* CountThread.java kO-(~];
* S 6,.FYH
* Created on 2007年1月1日, 下午4:57 /H+a0`/
* 'A[dCc8O
* To change this template, choose Tools | Options and locate the template under M&
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* the Source Creation and Management node. Right-click the template and choose 4ss4kp_>
* Open. You can then make changes to the template in the Source Editor. wH6aAV~1
*/ A.w:h;7
5E_YEBO/
package com.tot.count; 2dgd~
import tot.db.DBUtils; !5?<% *
import java.sql.*; *_g$MI
/** da~],MN
* 3{(/x1a,4
* @author sUm'
*/ 7T'B6`-Ox
public class CountControl{ B,fo(kG
private static long lastExecuteTime=0;//上次更新时间 FU<Jp3<%
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 XBw)H
/** Creates a new instance of CountThread */ S#[j )U-
public CountControl() {} :P=(k2
public synchronized void executeUpdate(){ 9JKEw
Connection conn=null; EAby?51+
PreparedStatement ps=null; F1Bq$*'N$w
try{ _t}WsEQ+P
conn = DBUtils.getConnection(); -1@<=jX3_
conn.setAutoCommit(false); $
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ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); b\+`e b8_
for(int i=0;i<CountCache.list.size();i++){ ;P&OX5~V
CountBean cb=(CountBean)CountCache.list.getFirst(); N$:8,9.z
CountCache.list.removeFirst(); w"&n?L
ps.setInt(1, cb.getCountId());
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ps.executeUpdate();⑴ FN) $0
//ps.addBatch();⑵ b*Q&CL
} !_Z&a
//int [] counts = ps.executeBatch();⑶ "G9xMffW
conn.commit(); ?#Q #u|~
}catch(Exception e){ F^fdIZx
e.printStackTrace(); 2T[9f;jM'
} finally{ ps DetP
try{ Xm2z}X(%
if(ps!=null) { S?BG_J6A7
ps.clearParameters(); 26x[X.C:
ps.close(); 1 I",L&S1
ps=null; Ef13Q]9|
} &UlWCOo8
}catch(SQLException e){} CQDkFQq-dq
DBUtils.closeConnection(conn); eO[b1]WLP
} (0kK_k'T
} @2v_pJy^
public long getLast(){ 2gVm9gAHUd
return lastExecuteTime; 2SR: FUV/
} t#eTV@-
public void run(){ !m?-!:
long now = System.currentTimeMillis(); d9|<@A
if ((now - lastExecuteTime) > executeSep) { 3|Xyl`i4o
//System.out.print("lastExecuteTime:"+lastExecuteTime); tcog'nAz
//System.out.print(" now:"+now+"\n"); }?v )N).kW
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); Z>#i**
lastExecuteTime=now; -!]ZMi9
executeUpdate(); 4#hSJ(~7S
} cDkf qcC
else{ dzrio-QU~
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); G?Hdq;
} ~gRf:VXX=_
} 4)o
} ?#UO./ "
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 OprkR
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类写好了,下面是在JSP中如下调用。 w$-6-rE]d
S#}
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<% BsYa3d=}
CountBean cb=new CountBean(); YLn?.sV{[0
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); ~z;FP$U
CountCache.add(cb); O463I.XAP
out.print(CountCache.list.size()+"<br>"); 2*#|Nj=^
CountControl c=new CountControl(); 4d;8`66O
c.run(); <0q;NrvUb
out.print(CountCache.list.size()+"<br>"); by/jYg)+
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