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: Q2R-z^pd
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CountBean.java w&+\Wo;([b
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/* U$@83?O{iM
* CountData.java 49y*xMn
* 7BrV<)ih{*
* Created on 2007年1月1日, 下午4:44 5\+EHW!o
* 45r|1<R o
* To change this template, choose Tools | Options and locate the template under iiehrK&T!
* the Source Creation and Management node. Right-click the template and choose DrV0V
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* Open. You can then make changes to the template in the Source Editor. |?|K\UF(Y
*/ 6#?NL]A
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package com.tot.count; g(aNyn
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/** Ku&*`dME
* {SHqW5VX
* @author
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*/ iZu:uMoc
public class CountBean { lSs^A@s
private String countType; aC}vJ93i
int countId; xtu]F
/** Creates a new instance of CountData */ n1JC?+
public CountBean() {} UJ9q-r
public void setCountType(String countTypes){ $KH@,;Xz
this.countType=countTypes; wC(XRqlE
} 0JrK/Ma3
public void setCountId(int countIds){ AAdD\%JZ
this.countId=countIds; _p$"NNFN
} HcDyD0;L.
public String getCountType(){ "sSjVu
return countType; S--/<a2
} K#iK6)tS
public int getCountId(){ #EEG>M*xB
return countId; s|BX>1
} Y)5)s0}
} @>gD1Q7v b
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CountCache.java gRw.AXRa
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/* dqL-'
* CountCache.java KWtu,~O_u
* Sn+FV+D
* Created on 2007年1月1日, 下午5:01 u% r!?-z
* nh?9R&
* To change this template, choose Tools | Options and locate the template under 4*YOFU}l
* the Source Creation and Management node. Right-click the template and choose L;4[ k;5
* Open. You can then make changes to the template in the Source Editor. QId"Cl)3
*/ d~vTD|Et
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package com.tot.count; d"LoK,p#
import java.util.*; tru;;.lj8K
/** fuQ4rt[i
* o- cj&Cv%
* @author X9DM^tt
*/ ?' TA!MR
public class CountCache { 3^j~~"2,w
public static LinkedList list=new LinkedList(); y @]8Ep
/** Creates a new instance of CountCache */ V^9$t/c&
public CountCache() {} |K'Gw}fX/
public static void add(CountBean cb){ ,^n-L&
if(cb!=null){ 3j]UEA^
list.add(cb); d.LOyO
} Dl>*L
} :h^O{"au^
} 3$MYS^D
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CountControl.java T$#FAEz
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/* Bm65W
* CountThread.java 9k(*?!\;
* rSM$E
* Created on 2007年1月1日, 下午4:57 kQqBHA
* 2Px$0&VN
* To change this template, choose Tools | Options and locate the template under XhQw+j~1.
* the Source Creation and Management node. Right-click the template and choose z"G`o"4
V
* Open. You can then make changes to the template in the Source Editor. $'WapxF
*/ r'Hy}HWuF
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package com.tot.count; uWJ#+XK.
import tot.db.DBUtils; N8Rm})
import java.sql.*; deR$
/** L$oia)%t-
* ;,Of\Efc|
* @author 7KvXTrN!9
*/ CsJ)Z%4_
public class CountControl{ % JgRcx
private static long lastExecuteTime=0;//上次更新时间 iSSc5ek4
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 e{^:/WcYB
/** Creates a new instance of CountThread */ .Z(S4wV
public CountControl() {} stf,<W
public synchronized void executeUpdate(){ +a7EsR
Connection conn=null; U:s}/to
PreparedStatement ps=null; 5KL9$J9k
try{
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conn = DBUtils.getConnection(); Bf D,z
conn.setAutoCommit(false); [[";1l
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); OqEg{o5 a&
for(int i=0;i<CountCache.list.size();i++){ {^PO3I
CountBean cb=(CountBean)CountCache.list.getFirst(); Fw(b1 d>E
CountCache.list.removeFirst(); ZXFAuF
ps.setInt(1, cb.getCountId()); &:!ZT=
ps.executeUpdate();⑴ &4w\6IR
//ps.addBatch();⑵ V6DBKq
} d,GtH)( s
//int [] counts = ps.executeBatch();⑶ [ u`17hyX
conn.commit(); o2[vM$]
}catch(Exception e){ .g6PrhzFbk
e.printStackTrace(); Pg!;o=
{M
} finally{ n"^/UQ|#j
try{ h,!G7V
if(ps!=null) { h|(ZXCH
ps.clearParameters(); e>])m3xvn
ps.close(); rW=k%#
p
ps=null; hQd@bN8
} }}4sh5z
}catch(SQLException e){} 4yJ*85e]
DBUtils.closeConnection(conn); @%I_&!d
} >?\v@
} zIAu3
public long getLast(){
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return lastExecuteTime; X/-
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} = )JVT$]w
public void run(){ yr/]xc$
long now = System.currentTimeMillis(); vp )}/&/
if ((now - lastExecuteTime) > executeSep) { I =tyQ`
//System.out.print("lastExecuteTime:"+lastExecuteTime); 4~MJ4:
//System.out.print(" now:"+now+"\n"); Yj^avO=;
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); 1sIy*z
lastExecuteTime=now; 7dM6;`V^
executeUpdate(); &;~2sEo,
}
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else{ LK
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); ei+9G,
} Tc'{i#%9j
} #f|NM7
} 'XZI{q2i
//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 0i5T]
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类写好了,下面是在JSP中如下调用。 EMVoTW)z
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<% *MnG-\{j
CountBean cb=new CountBean(); pr[B$X.V
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); i&}zcGC
CountCache.add(cb); tn:/pPap
out.print(CountCache.list.size()+"<br>"); ~7,2N.vO2
CountControl c=new CountControl(); azR;*j8Q'
c.run(); QKUBh-QFK
out.print(CountCache.list.size()+"<br>"); 6h0U
%>