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: tBWrL{xLe
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CountBean.java E \EsWb
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/* JPUW6e07o
* CountData.java ,0Hr2*p
* mh#a#<
* Created on 2007年1月1日, 下午4:44 4G0m\[Du
* (Q!}9K3
* To change this template, choose Tools | Options and locate the template under .},'~NM]
* the Source Creation and Management node. Right-click the template and choose 7`Ak)F:V
* Open. You can then make changes to the template in the Source Editor. \fdv]f
*/ `r':by0M
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package com.tot.count; 9};8?mucr
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/** FUb\e-Q=
* Y%^w:|f^
* @author !zpRrx_
*/ k FD;i
public class CountBean { n\'4
private String countType; yYYSeH
int countId; B{#I:Rs9
/** Creates a new instance of CountData */ (gU!=F?#m
public CountBean() {} T/~f~Z z
public void setCountType(String countTypes){ Bahm]2
this.countType=countTypes; |F[+k e
} KqJs?Won
public void setCountId(int countIds){ 50wulGJud
this.countId=countIds; }?i0
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} 69NeQ$](
public String getCountType(){ {duz\k2
return countType; }C?'BRX
} QO~P7r|A
public int getCountId(){ uyWunpT
return countId; 2- h{N
} q:0N<$63
} ((;!<5-`s
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CountCache.java @n /nH?L
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/* $( kF#
* CountCache.java "|q&ea rc
* #q$HQ&k
* Created on 2007年1月1日, 下午5:01 ZJJY8k `
* O
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* To change this template, choose Tools | Options and locate the template under v{N`.~,^
* the Source Creation and Management node. Right-click the template and choose pE0Sw}A:9
* Open. You can then make changes to the template in the Source Editor. 2MIi=c:oqK
*/ ^
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package com.tot.count; BwpqNQN
import java.util.*; 7S:\"A7
/** lb3bm)@:
* xm~`7~nFR
* @author _D&598 xx
*/ |SSSH
public class CountCache { /C:gKy4
public static LinkedList list=new LinkedList(); s!zx}
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/** Creates a new instance of CountCache */ G>}255qY
public CountCache() {} gZXi]m&
public static void add(CountBean cb){ AV]2euyn
if(cb!=null){ :eCwY
list.add(cb); &
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} 3;9^
} Mfuv0P~
} V2EUW!gn
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CountControl.java R) h#Vc(
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/* V=l0(03j~
* CountThread.java V1zmG y
* Gb6 'n$g
* Created on 2007年1月1日, 下午4:57 _N cR)2
* H%tdhu\e
* To change this template, choose Tools | Options and locate the template under (%6P0*
* the Source Creation and Management node. Right-click the template and choose %[TR^Th6
* Open. You can then make changes to the template in the Source Editor. :3Ox~o
*/ |HQW0
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package com.tot.count; !f[_+CD
import tot.db.DBUtils; TIDO@NwF
import java.sql.*; Wn2NMXK
/**
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* hn@08t G
* @author cV6D<,)
*/ ED gag
public class CountControl{ .`eN8Dl1
private static long lastExecuteTime=0;//上次更新时间 h[Y1?ln&h
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 K\r8g=U
/** Creates a new instance of CountThread */ + &Eqk
public CountControl() {} .L~AL|2_
public synchronized void executeUpdate(){ (w3YvG.
Connection conn=null; 2/^3WY1U
PreparedStatement ps=null; </zEg3F\
try{ C,r;VyW6BI
conn = DBUtils.getConnection(); <%eG:n,#
conn.setAutoCommit(false); U8?mc
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); d7upz]K9g
for(int i=0;i<CountCache.list.size();i++){ [z{1*Xc
CountBean cb=(CountBean)CountCache.list.getFirst(); g!|kp?
CountCache.list.removeFirst(); 9Y9GwL]T
ps.setInt(1, cb.getCountId()); :5<UkN)R(
ps.executeUpdate();⑴ #;yZ
//ps.addBatch();⑵ =;
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} N4!O.POP
//int [] counts = ps.executeBatch();⑶ Ti5-6%~&
conn.commit(); 6H$FhJF
}catch(Exception e){ -Q*gW2KmV
e.printStackTrace(); 6cXyJW
} finally{ <]2w n
try{ I\ob7X'Xu!
if(ps!=null) { lymCH
ps.clearParameters(); NXrlk
ps.close(); CD~.z7,LC
ps=null; >kVz49j
} &h/Xku&0
}catch(SQLException e){} a`>B Ly5o
DBUtils.closeConnection(conn); U5de@Y
} h2R::/2.
} 7{*>agQh
public long getLast(){ gM:".Ee
return lastExecuteTime; q 2E_A
} f
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public void run(){ ;e *!S}C,
long now = System.currentTimeMillis(); %h!B^{0
if ((now - lastExecuteTime) > executeSep) { sO@Tf\d
//System.out.print("lastExecuteTime:"+lastExecuteTime); zrb}_
//System.out.print(" now:"+now+"\n"); Q![@c
// System.out.print(" sep="+(now - lastExecuteTime)+"\n");
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lastExecuteTime=now; W'TZ%K) I
executeUpdate(); f-Z/tfC
} 26h21Z16q
else{ t{{QE:/
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); b\2
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} 5$k:t
} [4f{w%~^
} j\M?~=*w
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 @o`AmC.
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类写好了,下面是在JSP中如下调用。 '`Hr}
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<% ?Ir:g=RP*
CountBean cb=new CountBean(); #ABZ&Z
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); tR$NRMZ.
CountCache.add(cb); i/Zd8+.n$
out.print(CountCache.list.size()+"<br>"); -iZ`Y?
CountControl c=new CountControl(); 3Y$GsN4ln
c.run(); #H~64/
out.print(CountCache.list.size()+"<br>"); ~t~|"u"P
%>