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: Rm,[D)D^0N
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CountBean.java RI[7M (
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/* 2d5}`>
* CountData.java pIID=8RJ.
*
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* Created on 2007年1月1日, 下午4:44 r3+<r<gs
* PZ
* To change this template, choose Tools | Options and locate the template under eD*?q7
* the Source Creation and Management node. Right-click the template and choose iXUWIgr
* Open. You can then make changes to the template in the Source Editor.
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*/ D rF
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package com.tot.count; G*P[z'K=
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/** %|: ;Ti
* l?[{?Luq
* @author itqQ)\W
*/ 7>nhIp))
public class CountBean { 2gQY8h8
private String countType; 7.wR"1p#
int countId; _-4n~(
/** Creates a new instance of CountData */ ^?$D.^g
public CountBean() {} |_l<JQvf`E
public void setCountType(String countTypes){ tyc8{t#Z
this.countType=countTypes; C-s>1\I
} { c v;w
public void setCountId(int countIds){ qiG]nCq
this.countId=countIds; ;Ri 3#*a=
} -vyIOH,
public String getCountType(){ $Nj'OJSj%
return countType; _v1bTg"?
} +IwdMJ8&8
public int getCountId(){ 7!O^;]+,
return countId; W0VA'W
} XHWh'G9
} kmZ.U>#
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CountCache.java *e(:["v
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/* \w{@u)h
* CountCache.java Ty`-r5
* 17e=GL
* Created on 2007年1月1日, 下午5:01 mZ`1JO9
* ^dFhg_GhF
* To change this template, choose Tools | Options and locate the template under _L$)2sl1R
* the Source Creation and Management node. Right-click the template and choose }*?yHJ3
* Open. You can then make changes to the template in the Source Editor. $-m@KB
*/ \9046An
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package com.tot.count; PPUEkvH
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import java.util.*; 7sj<|g<h(_
/** =hJfL}&O3
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* @author 5iP8D<;o5
*/ [_j6cj]
public class CountCache { (F/HU"C
public static LinkedList list=new LinkedList();
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/** Creates a new instance of CountCache */ pI
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public CountCache() {} %,33gZzf
public static void add(CountBean cb){ !A~d[</]m
if(cb!=null){ nHrP>zN
list.add(cb); ^gd<lo g
} [6O04"6K
} $2Ka u 1
} :aHcPc:
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CountControl.java ;?0_Q3IML
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/* /j11,O?72
* CountThread.java ^)|&|
* }6<)yW}U
* Created on 2007年1月1日, 下午4:57 =D{B}=D\IM
* VF\{ra;
* To change this template, choose Tools | Options and locate the template under w
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* the Source Creation and Management node. Right-click the template and choose F@<O;b#Ip
* Open. You can then make changes to the template in the Source Editor. hXNH"0VCV
*/ +a #lofhv
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package com.tot.count; Bw6 L;Vu
import tot.db.DBUtils; ~xw5\Y^
import java.sql.*; `n6/ A)
/** Yhe+u\vGs\
* 10?qjjb&
* @author #^Ys{
*/ `-o5&>'nf
public class CountControl{ ,6DD=w 0r
private static long lastExecuteTime=0;//上次更新时间 N ,+(>?yE
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 *_PPrx5
/** Creates a new instance of CountThread */ B=r0?%DX"1
public CountControl() {} vm|!{5l:=y
public synchronized void executeUpdate(){ EA6t36|TX
Connection conn=null; R+d<
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PreparedStatement ps=null; ^xt9pa$f
try{ `YU=~xQ
conn = DBUtils.getConnection(); A?DB#-z.r
conn.setAutoCommit(false); Nl
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ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); $6#
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for(int i=0;i<CountCache.list.size();i++){ yQ'eu;+]
CountBean cb=(CountBean)CountCache.list.getFirst(); "?P[9x}
CountCache.list.removeFirst(); vnTq6:f#M
ps.setInt(1, cb.getCountId()); ^Z#@3=
ps.executeUpdate();⑴ |:N>8%@6c
//ps.addBatch();⑵ @ ICbKg:
} +qhnP$vIe
//int [] counts = ps.executeBatch();⑶ Y87XLvig}
conn.commit(); {c@G$
}catch(Exception e){ }a ^|L"
e.printStackTrace(); qi&D+~Gv!
} finally{ 8 aZ$5^z
try{ N 'i,>
if(ps!=null) { ~,gLplpG0
ps.clearParameters(); nkRK+~>
ps.close(); nVXg,Jl
ps=null; .TJ">?
} Ig9d#c
}catch(SQLException e){} 1%jH^,t/m
DBUtils.closeConnection(conn); ZE
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} f?^S bp
} +I@cO&CY|
public long getLast(){ H2U:@.o2&
return lastExecuteTime; U-g9C.
} HxIoA
public void run(){ \2>?6zs
long now = System.currentTimeMillis(); hVM2/j
if ((now - lastExecuteTime) > executeSep) { I+",b4
//System.out.print("lastExecuteTime:"+lastExecuteTime); 6G}c1nWU
//System.out.print(" now:"+now+"\n"); .,M;huRg
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); AF$\WWrB
lastExecuteTime=now; aMJ;bQD
executeUpdate(); 4,~tl~FD
} ne*#+Q{E
else{ =EpJZt
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); H\#:,s {1
} ,r`UBQ}?
} q@ZlJ3%l,
} 6t7fa<
//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 x8\<qh*:
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类写好了,下面是在JSP中如下调用。 Qqq
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<% ]?&FOzN5$P
CountBean cb=new CountBean(); -DCa
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); ,{KCY[}|
CountCache.add(cb); S4bBafj[I
out.print(CountCache.list.size()+"<br>"); 7&+Ys
CountControl c=new CountControl(); wz=z?AZW
c.run(); cAEok P
out.print(CountCache.list.size()+"<br>"); S
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