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: D n^RZLRhy
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CountBean.java 7@:uVowQ
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/* F"_SCA?9?
* CountData.java ~FJd{$2x`
* (RQ kwu/
* Created on 2007年1月1日, 下午4:44 Vki3D'.7N
* Gg_i:4F
* To change this template, choose Tools | Options and locate the template under nI-\HAX
* the Source Creation and Management node. Right-click the template and choose v vFX\j3
* Open. You can then make changes to the template in the Source Editor. yzYPT}t
*/ 9G&l{7 =
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package com.tot.count; tjGQ0-Lo
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/** n-uoY<;hp
* IRLT-
* @author C{4[ 7
*/ 3ILEc:<0J
public class CountBean { mZm wCS8
private String countType; dx|j,1e
int countId; I~Ziq10
/** Creates a new instance of CountData */ #=h~Lr'UH
public CountBean() {} V^"5cW
public void setCountType(String countTypes){ 7JjTm^bu
this.countType=countTypes; 8uNq353
} r'"H8>UZ%
public void setCountId(int countIds){ J 5~bs*a8
this.countId=countIds; 8^2Q ~{i
} hl8[A-d(R
public String getCountType(){ `uY77co6
return countType; w18kTa!4@
} HI55):Eb
public int getCountId(){ Z{|wjZb(
return countId; )jvYJ9s
} 2!}5shB
} N|wI=To
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CountCache.java X180_Kt2
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/* oJEind>8O
* CountCache.java BTqY_9
* ;V@o 2a
* Created on 2007年1月1日, 下午5:01 =5isT
* ;BsyN[bF
* To change this template, choose Tools | Options and locate the template under w(0's'
* the Source Creation and Management node. Right-click the template and choose ]FP(,:Yw
* Open. You can then make changes to the template in the Source Editor. R]H/Jv\'
*/ R!5j1hMN`
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package com.tot.count; It&$R`k
import java.util.*; !;>j(xc
/** e2~&I`ct
* "{Lp'+wNw
* @author [WW3'= e^
*/ 0@k)Cz[0;
public class CountCache { DHQavHqbZ
public static LinkedList list=new LinkedList(); Dm2&}{&K
/** Creates a new instance of CountCache */ qf-0 | w
public CountCache() {} ]hRCB=G
public static void add(CountBean cb){ !/2uO5
if(cb!=null){ B*W)e$
list.add(cb); ?U$H`[VF}
} 4CCtLHb
} ?hHVawt
} K?`Fpg(
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CountControl.java ,6J]oX
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/* {B+|",O5)
* CountThread.java u 6A!Sw
* +es|0;Z4yP
* Created on 2007年1月1日, 下午4:57 4Qwv:4La
* F/}(FG<'>I
* To change this template, choose Tools | Options and locate the template under }&!fT\4
* the Source Creation and Management node. Right-click the template and choose hhRUC&Y%V
* Open. You can then make changes to the template in the Source Editor. Qu]F<H*Y|
*/ <a_ytSoG1
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package com.tot.count; xO3-I@
import tot.db.DBUtils; U~H]w,^
import java.sql.*; o y{
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/** *7cc4 wGQ
* \+3amkBe
* @author NFsj
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*/ IHC
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public class CountControl{ @,kR<1
private static long lastExecuteTime=0;//上次更新时间 B bP&-c
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 `0)'&HbLY
/** Creates a new instance of CountThread */ : ZehBu
public CountControl() {} N#C,q&;
public synchronized void executeUpdate(){ .A%*AlX
Connection conn=null; }*Z *wC
PreparedStatement ps=null; z"D'rHxy
try{ s&.VU|=VQ@
conn = DBUtils.getConnection(); !I)wI~XF)5
conn.setAutoCommit(false); 3pU/Zbb,:
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); Xlg0u.
for(int i=0;i<CountCache.list.size();i++){ 4Kl{^2
CountBean cb=(CountBean)CountCache.list.getFirst(); ?azi(ja
CountCache.list.removeFirst(); s[2>r#M
ps.setInt(1, cb.getCountId()); 8>4@g!9E
ps.executeUpdate();⑴ ]&+,`1_q
//ps.addBatch();⑵ S~GL_#a
} I)s~kA.e
//int [] counts = ps.executeBatch();⑶ zfGS=@e]G
conn.commit(); ZlEQzL~
}catch(Exception e){ ?R#?=<VkG
e.printStackTrace(); *gGL5<%T:
} finally{ S29k IJ
try{ 3]MSS\uB
if(ps!=null) { @3g$H[}
ps.clearParameters(); dAba'|Y
ps.close(); xr yXO(
ps=null; E'KKR1t
} E=3UaYr
}catch(SQLException e){} S:F8`Gh
DBUtils.closeConnection(conn); Aq3.%,X2H
} u*w'.5l
} FV~ENpncP
public long getLast(){ d$f3Cre
return lastExecuteTime; (,P6cWt}"
} o W<Z8s;p
public void run(){ )y#~eYn
long now = System.currentTimeMillis(); zLt7jxx
if ((now - lastExecuteTime) > executeSep) { x9Oo.[
//System.out.print("lastExecuteTime:"+lastExecuteTime); `2I<V7SF$
//System.out.print(" now:"+now+"\n"); v$JhC'
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); {BI5lvx:
lastExecuteTime=now; 1ZZ}ojq
executeUpdate(); P70]Ju
} | >
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else{ D #Ku5~j
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); 3q}fDM(@J
} x )w6
} ~[*\YN);
} gR#lRA/
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 wgPkSsuBuC
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类写好了,下面是在JSP中如下调用。 z
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<% :i};]pR
CountBean cb=new CountBean(); X}5}M+'~
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); \g;o9}@3~
CountCache.add(cb); ud`!X#e~
out.print(CountCache.list.size()+"<br>"); c|hT\1XR,
CountControl c=new CountControl(); <$+Cd=71\
c.run(); N3U.62
out.print(CountCache.list.size()+"<br>"); \ )'`F;
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