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: ieZ$@3#&z
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CountBean.java ihrf/b
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/* Bl b#h
* CountData.java #
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* >+M[!;m}
* Created on 2007年1月1日, 下午4:44 1K Fd
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* LCorT-
* To change this template, choose Tools | Options and locate the template under cMY}Y
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* the Source Creation and Management node. Right-click the template and choose !85bpQ.
* Open. You can then make changes to the template in the Source Editor. @z1QoZ^w
*/ /vSGmW-*
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package com.tot.count; w}3N!jNDv
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/** 'nTlCYT
* 5P!ZGbG
* @author sX1DbEjj[o
*/ eFiG:LS7
public class CountBean { rCPIz<
private String countType; l
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int countId; +#Pb@^6"m
/** Creates a new instance of CountData */ ~B;}jI]d[
public CountBean() {} p1UloG\
public void setCountType(String countTypes){ !n-Sh<8
this.countType=countTypes;
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} =yod
public void setCountId(int countIds){ jEBn"]\D
this.countId=countIds; '[$KG
} Lf9hOMHx
public String getCountType(){ IBa0O|*6
return countType; ZXnacc~s
} wpZ"B+oK!
public int getCountId(){ i@rtt
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return countId; m*y&z'e\
} :E")Zw&sW3
} 3 yx[*'e$
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CountCache.java yQhO-jT
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/* DtANb^
* CountCache.java Q:P)g#suc
* /9_%NR[
* Created on 2007年1月1日, 下午5:01 kK75 (x
* N@|<3R!N*e
* To change this template, choose Tools | Options and locate the template under KdoI
* the Source Creation and Management node. Right-click the template and choose 'l'3&.{Yfk
* Open. You can then make changes to the template in the Source Editor. /r7xA}se^
*/ cSPQ
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package com.tot.count; (2b${ Q@V
import java.util.*; ZxtO.U2
/** dXTD8 )&
* f-M:ap(O
* @author _$UJ'W})/
*/ h7Uj "qH
public class CountCache { ~xqiasE#K
public static LinkedList list=new LinkedList(); 'w,gYW
/** Creates a new instance of CountCache */ ,>B11Z}PH
public CountCache() {} a_Xwi:e<
public static void add(CountBean cb){ GFFwk4n1
if(cb!=null){ zQ+Mu^|u+
list.add(cb); Mxl;Im]!`.
} 3k'Bje?9~
} D&FDPaJM
} HGYTh"R
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CountControl.java 9n(68|^$
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/* LzL)qdL
* CountThread.java aL:|Dr3SX
* ec;
* Created on 2007年1月1日, 下午4:57 yy3x]%KK
* QD7KE6KP'
* To change this template, choose Tools | Options and locate the template under Z]Bv
* the Source Creation and Management node. Right-click the template and choose n$2oM5<
* Open. You can then make changes to the template in the Source Editor. *)RKU),3nL
*/ ZiZ @3O6
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package com.tot.count; ?pZ"7kkD
import tot.db.DBUtils; aV$kxzEc
import java.sql.*; Al?%[-u
/** U5C]zswL
* Dn)yBA%
* @author },d^y:m
*/ bD{tsxm[9
public class CountControl{ v]M:HzP
private static long lastExecuteTime=0;//上次更新时间 S${%T$>
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 8gavcsVE[
/** Creates a new instance of CountThread */ ;+DEU0|pe
public CountControl() {} DinZZ
public synchronized void executeUpdate(){ deAV:c
Connection conn=null; sUlf4<_zW
PreparedStatement ps=null; 81EEYf
try{ X{ x(p
conn = DBUtils.getConnection(); {#kCqjWG
conn.setAutoCommit(false); +(=-95qZ
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); s'yR2JYv
for(int i=0;i<CountCache.list.size();i++){ 7RDmvWd-'?
CountBean cb=(CountBean)CountCache.list.getFirst(); XQ=% a5w
CountCache.list.removeFirst(); q;[HUyY,
ps.setInt(1, cb.getCountId()); R[zN?
ps.executeUpdate();⑴ "m {i`<,
//ps.addBatch();⑵ =Fc]mcJ69
} Ja~8ZrcY
//int [] counts = ps.executeBatch();⑶ {Fwvuk
conn.commit(); se.HA
}catch(Exception e){ ogIu\kiZ
e.printStackTrace(); w)ki<Dudg
} finally{ *f 7rLM*
try{ w<H2#d>5!@
if(ps!=null) { j1`<+YT<#
ps.clearParameters(); (W#CDw<ja
ps.close(); @&G}'6vF!
ps=null; @Y `Z3LiR$
} qRaPh:Q'
}catch(SQLException e){} |= cc >]
DBUtils.closeConnection(conn); &Y^4>y%
} ^1~lnD~0
} L*4"D4V
public long getLast(){ hqln6m
return lastExecuteTime; C!:Lk,Z
} C7F\Y1Wj
public void run(){ 8o+:|V~X
long now = System.currentTimeMillis(); iT:i
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if ((now - lastExecuteTime) > executeSep) { 0S:&wb
//System.out.print("lastExecuteTime:"+lastExecuteTime);
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//System.out.print(" now:"+now+"\n"); o@N[O^Q
V
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); i#4+l$q
lastExecuteTime=now; T%oJmp?0
executeUpdate(); 8x-19#
} /:]<z6R
else{ y0Gblza
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); 2H w7V3q
} 4`"}0:t.
} Ce-=
-
} Q3%]
//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 QGI@5
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类写好了,下面是在JSP中如下调用。 x %`YV):*
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<% x2t&Wpvt
CountBean cb=new CountBean(); i7-i!`<
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); @]IRB1X
CountCache.add(cb); XYR
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out.print(CountCache.list.size()+"<br>"); 9QX!HQ|5y8
CountControl c=new CountControl(); q#AIN`H
c.run(); p*5_+u
out.print(CountCache.list.size()+"<br>"); WZ>nA [/
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