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: Hz8`)cv`
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CountBean.java ef&@aB
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/* Jt6J'MOq
* CountData.java bFezTl{M
* 5V~p@vCx
* Created on 2007年1月1日, 下午4:44 A=UIN!
* Fz&ilB
* To change this template, choose Tools | Options and locate the template under 0@lC5-=
* the Source Creation and Management node. Right-click the template and choose o2 d~
* Open. You can then make changes to the template in the Source Editor. suFOc
*/ #@^w>D6W
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package com.tot.count; lM^!^6=v0l
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/** /\cu!yiX
* oh~
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* @author _a$DY,;
*/ I&8SP$S>J
public class CountBean { 2j7d$y*'
private String countType; %J7mZB9
int countId; v8bl-9DQ
/** Creates a new instance of CountData */ xsDa!
public CountBean() {} <C%-IZv$
public void setCountType(String countTypes){ ~88 Tz+
this.countType=countTypes; 'S7@+kJ
} \t# 9zn>
public void setCountId(int countIds){ G.nftp(*}
this.countId=countIds; 5w)^~#'
} 9jGuelwN
public String getCountType(){ n/oipiYx
return countType; d[e:}1
} |$w={N^4
public int getCountId(){ "P5bYq%0v
return countId; $H-D9+8 7
} 1 {x~iZa
} @:+n6
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CountCache.java 6'Yn|A
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/* eH%L?"J~:
* CountCache.java ?lDcaI>+n
* S~Iw?SK3
* Created on 2007年1月1日, 下午5:01 ^[}0&_L
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* w2N3+Tkg
* To change this template, choose Tools | Options and locate the template under >xV<nLf/
* the Source Creation and Management node. Right-click the template and choose ;Z1U@2./
* Open. You can then make changes to the template in the Source Editor. (SsH uNt.
*/ ]Wd`GI
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package com.tot.count; $dTfvd
import java.util.*; 9id~NNr7
/** o1X/<.0+
* GGc_9?h
* @author "Dl9<EZ
*/ ?e y&Un"
public class CountCache { 6!%d-Z7)
public static LinkedList list=new LinkedList(); b^,Mw8KsO
/** Creates a new instance of CountCache */ x)VIA]
public CountCache() {} ;5Vk01R
public static void add(CountBean cb){ +yb$[E*
if(cb!=null){ f'6qJk%J
list.add(cb); )xvx6?Ah|
} R^yZG{?t
} _d[2_b1
} LlA`QLe
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CountControl.java nN=:#4
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/* >!Ap/{2
* CountThread.java nK jeH@
* \gp,Txueb
* Created on 2007年1月1日, 下午4:57 AO}i@YJth
* _Hd1sx
* To change this template, choose Tools | Options and locate the template under <a+eF}*2
* the Source Creation and Management node. Right-click the template and choose X}j'L&{F@
* Open. You can then make changes to the template in the Source Editor. 0?F@iB~1F
*/ MeI2i
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package com.tot.count; noaN@K[GO
import tot.db.DBUtils; !/4V^H
import java.sql.*; c[h'`KXJf-
/** g/l0}%
* &=z1$ih>2\
* @author o7Cnyy#:
*/ lv00sa2z
public class CountControl{ F8S~wW=\w
private static long lastExecuteTime=0;//上次更新时间 ,dZ#,<
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 ^%oG8z,L
/** Creates a new instance of CountThread */ LZQFj/,Jg
public CountControl() {} +f\pk \Ith
public synchronized void executeUpdate(){ i|c`M/) h:
Connection conn=null; ST:
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PreparedStatement ps=null; UN *dU
try{ r ,3Ww2X-
conn = DBUtils.getConnection(); Fp5NRM*-!
conn.setAutoCommit(false); @cu}3>
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); ]@/^_f>D
for(int i=0;i<CountCache.list.size();i++){ ?Rt1CDu
CountBean cb=(CountBean)CountCache.list.getFirst(); x0u?*5-t
CountCache.list.removeFirst(); of+phMev
ps.setInt(1, cb.getCountId()); &ppE|[{
ps.executeUpdate();⑴ 7O8V1Tt
//ps.addBatch();⑵ /OhaERv
} ]Z.<c$
//int [] counts = ps.executeBatch();⑶ m]0^
conn.commit(); iM?I
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}catch(Exception e){ 2H?I'<NoC
e.printStackTrace(); Bbl)3$`,
} finally{ O^X[9vrW
try{ m~Y'$3w
if(ps!=null) { ' 1P=^
ps.clearParameters(); xm}q6>jRV
ps.close(); vbRrk($`
ps=null; (>rS
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} X(r)Z\
}catch(SQLException e){} ?AV&@EX2C
DBUtils.closeConnection(conn); 1Lm].tq
} Ad]<e?oN=
} O)R7t3t
public long getLast(){ H
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return lastExecuteTime; fa!3/X+
} 1u"R=D9p,=
public void run(){ * ?
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long now = System.currentTimeMillis(); ,+ns
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if ((now - lastExecuteTime) > executeSep) { ~K5Cr
//System.out.print("lastExecuteTime:"+lastExecuteTime); Y<p zy8z
//System.out.print(" now:"+now+"\n"); u<l#xud
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); Sni&?tcY
lastExecuteTime=now; a.
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executeUpdate(); -"~L2f"?
} hAV2F#
else{ X'V+^u@W
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); D^66p8t
} k~0#'I9
} u^`eKak"l
} H|PrsGW
//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 *'Z-OY<V
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类写好了,下面是在JSP中如下调用。 uz*d^gr}
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<% KK:N [x
CountBean cb=new CountBean(); eQ$N:]
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); d32@M~vD
CountCache.add(cb); yJnPD/i
out.print(CountCache.list.size()+"<br>"); EKcC+g
CountControl c=new CountControl(); NNwc!x)*
c.run(); .D+RLO z
out.print(CountCache.list.size()+"<br>"); V3##
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%>