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: 6$=>ck P
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CountBean.java (=;'>*L(
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/* w0oTV;yh
* CountData.java =b>TF B=*N
* qHdUnW
* Created on 2007年1月1日, 下午4:44 , QWus"5H
* EPH" 5$8
* To change this template, choose Tools | Options and locate the template under P5oS 1iu*
* the Source Creation and Management node. Right-click the template and choose #$-?[c$>
* Open. You can then make changes to the template in the Source Editor. ab%I&B<b
*/ v;9(FLtL
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package com.tot.count; U5H%wA['m
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/** IF5-@hag,
* UH}lKc=t
* @author ~jzLw@"~$^
*/ :q*w_*w
public class CountBean { R6oD
private String countType; o5DT1>h
int countId; jOrfI-&.G
/** Creates a new instance of CountData */ 1/w8'Kf'u
public CountBean() {} h]t v+\0
public void setCountType(String countTypes){ 2|& S2uq
this.countType=countTypes; F0z7".)
} d~%7A5
public void setCountId(int countIds){ OUF%DMl4
this.countId=countIds; gj
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} Ys}^hy
public String getCountType(){ WPNw")t!
return countType; SJa>!]U'xI
} P-gj SE|yh
public int getCountId(){ .BBJhXtrdu
return countId; qve'Gm)
} La9}JvQoX
} [BJzZ>cY
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CountCache.java BlU&=;#r5>
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/* DC*MB:c#U
* CountCache.java @0P4pt;(
* 9t)Hi qj
* Created on 2007年1月1日, 下午5:01 *8?2+)5"
* L@s6u+uu
* To change this template, choose Tools | Options and locate the template under hx9t{Zi
* the Source Creation and Management node. Right-click the template and choose LOcZadr
* Open. You can then make changes to the template in the Source Editor. !37I2*+4
*/ pgh(~[
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package com.tot.count; S sW<,T
import java.util.*; Aipm=C8
/** lW-h
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* I8)D
* @author u%z'.#r; a
*/ (XmmbAbVom
public class CountCache { `G\Gk|4;2
public static LinkedList list=new LinkedList(); 0 {z8pNrc
/** Creates a new instance of CountCache */ l`N#~<.
public CountCache() {} %\sE \]K
public static void add(CountBean cb){ YCltS!k
if(cb!=null){ O{~Xp!QQt
list.add(cb); G>0d^bx;E
} P4_B.5rrJ
} hN!;Tny
} z=U+FHdh/-
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CountControl.java 6JZ>&HA
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/* v9*+@
* CountThread.java 8CUtY9.
* Gkem _Z
* Created on 2007年1月1日, 下午4:57 / kK*%TP
* /tj]^QspS
* To change this template, choose Tools | Options and locate the template under \}=T4w-e
* the Source Creation and Management node. Right-click the template and choose W@r<4?Oat
* Open. You can then make changes to the template in the Source Editor. W g7
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*/ &(Fm@ksh\
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package com.tot.count; Vlz\n
import tot.db.DBUtils; Lg!E
import java.sql.*; 3\j`g
/** 4Xa]yA =
* nfHjIYid
* @author bk<Rp84vL
*/ "0jwCX
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public class CountControl{ Q%d%Io\-t
private static long lastExecuteTime=0;//上次更新时间 erUK;+2g
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 7afG4
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/** Creates a new instance of CountThread */ U?f-/@fc
public CountControl() {} 83R s1}*
public synchronized void executeUpdate(){ {c_bNYoE
Connection conn=null; |"9&F
PreparedStatement ps=null; grgs r_)[
try{ _d3Z~cH
conn = DBUtils.getConnection(); 0~RD@>]
conn.setAutoCommit(false); mwLf)xt0'
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); PbZ%[F
for(int i=0;i<CountCache.list.size();i++){ 2?q>yL! Gz
CountBean cb=(CountBean)CountCache.list.getFirst(); gdTW
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CountCache.list.removeFirst(); ]R)wBug
ps.setInt(1, cb.getCountId()); 8=L"rekV_
ps.executeUpdate();⑴ {v]L|e%{
//ps.addBatch();⑵ a5t&{ajJ
} 8j70X <R
//int [] counts = ps.executeBatch();⑶ o"BED!/
conn.commit(); F<p`)?
}catch(Exception e){ v LN KX;9
e.printStackTrace(); rD <T
} finally{ H%Vf$1/TF
try{ vA_,TS#Bo
if(ps!=null) { J?m/u6
ps.clearParameters(); KMy"DVqE
ps.close(); ynM~&]fk#k
ps=null; &t<gK
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} +W[f>3`VQ
}catch(SQLException e){} ~$K{E[^<
DBUtils.closeConnection(conn); !q,'k2=b,
} rbdrs
} N9G xJ6
public long getLast(){ .lb]Xa*n
return lastExecuteTime; 1T|")D
} `B3-#!2X
public void run(){ Yl&[_
l
long now = System.currentTimeMillis(); d"?"(Q_8n
if ((now - lastExecuteTime) > executeSep) { m85ZcyW1T
//System.out.print("lastExecuteTime:"+lastExecuteTime); }hg=#*
//System.out.print(" now:"+now+"\n"); myX&Z F_9
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); D8,8j;
lastExecuteTime=now; V;SV0~&
executeUpdate(); [XI:Yf
} bi+M28m
else{ aQL0Sj:,
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); 8Snv, Lb`^
} A+Isk{d
} td%J.&K_*'
} RRS)7fFm
//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 D`^wj FF
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类写好了,下面是在JSP中如下调用。 Q]TZyk
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<% | 8mWR=9fs
CountBean cb=new CountBean(); akr2Os
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); :]F66dh+
CountCache.add(cb); {0F/6GwUC
out.print(CountCache.list.size()+"<br>"); O@@nGSc@
CountControl c=new CountControl(); #$S~QS.g
c.run(); {~O4*2zg;K
out.print(CountCache.list.size()+"<br>"); PUO7Z2
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