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: OyF=G^w
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CountBean.java _ERtL5^
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/* M|mfkIk0MB
* CountData.java ]}XDDPbZ}
* zMFTkDY
* Created on 2007年1月1日, 下午4:44 ld@+p
* eIY`RMo
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* To change this template, choose Tools | Options and locate the template under /*T^7Y&
* the Source Creation and Management node. Right-click the template and choose "TZY)\{L
* Open. You can then make changes to the template in the Source Editor. {pIh/0
*/ ]s AuL!
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package com.tot.count; G?'^"ae"Z
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/** z R?R,k)m
* jRU:un4
* @author N*}soMPV^.
*/ m0TV i] v
public class CountBean { JM,%|
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private String countType; 'E3T fM
int countId; 6/mz.,g2
/** Creates a new instance of CountData */ ,<t.Iz%
public CountBean() {} fq6Obh=A#
public void setCountType(String countTypes){ KtL?,zi
this.countType=countTypes; gGL}FNH
} Ne1Oz}
public void setCountId(int countIds){ 0BlEt1e2T
this.countId=countIds; /)sP, 2/
} .EL3}6"A
public String getCountType(){ ,s #~00C|
return countType; vS>'LX
} Vb`Vp(>AU
public int getCountId(){ J&>@>47
return countId; 6+IhI?lI=
} I]v2-rB&-
} P);s0Y|@H
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CountCache.java i *.Y
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/* g2|Myz)
* CountCache.java <J&S[`U!
* ,SR7DiYg
* Created on 2007年1月1日, 下午5:01 QPDh!A3T
* FpRYffT 9u
* To change this template, choose Tools | Options and locate the template under wS*r<zj
* the Source Creation and Management node. Right-click the template and choose #XDgvX >
* Open. You can then make changes to the template in the Source Editor. =#V^t$
*/ Z)`)9]*
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package com.tot.count; \dtiv& x
import java.util.*;
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/** t^~vi'bB
* 8@m$(I+
* @author eUA]OF@
*/ >o?v[:u*
public class CountCache { "#r)NYq`"|
public static LinkedList list=new LinkedList(); u;_h%z5K
/** Creates a new instance of CountCache */ 7EE{*}?0E
public CountCache() {} fZo#:"{/K
public static void add(CountBean cb){ .C%
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if(cb!=null){ )y,^M3$?C
list.add(cb); mQ:{>`
} q,,
} \0b}Z#'0
} $9,&BW_*
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CountControl.java GEWjQ;g
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/* )@N d3Z
* CountThread.java ZZT #V%Q=u
* kcCCa@~v
* Created on 2007年1月1日, 下午4:57 ^HC6v;K
* 6eV#x%z@v'
* To change this template, choose Tools | Options and locate the template under p@Y=6 Bw
* the Source Creation and Management node. Right-click the template and choose 'E_~|C
* Open. You can then make changes to the template in the Source Editor.
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*/ eO!9;dJ
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package com.tot.count; k8w\d+!v
import tot.db.DBUtils; 8z#Qp(he
import java.sql.*; pmNy=ZXx
/** 0kkDlWkzo
* =8\.fp
* @author ~5N}P>4*
*/ P1-eDHYw
public class CountControl{ FDz`U:8
private static long lastExecuteTime=0;//上次更新时间 R/hIXO
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 +X=*>^G(-
/** Creates a new instance of CountThread */ JXB)'d0
public CountControl() {} ,|]JaZq
public synchronized void executeUpdate(){ S[Du
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Connection conn=null; h:?^0b!@
PreparedStatement ps=null; 4@PA+(kvS
try{ 1F@j?)(
conn = DBUtils.getConnection(); yaj dRU
conn.setAutoCommit(false); $v0,)AL i
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); yix[zfQt0
for(int i=0;i<CountCache.list.size();i++){ +=3=% %?C
CountBean cb=(CountBean)CountCache.list.getFirst(); \vA*dQ-
CountCache.list.removeFirst(); a`!Jq'
ps.setInt(1, cb.getCountId()); "n%s>@$
ps.executeUpdate();⑴ Oidf\%!mvR
//ps.addBatch();⑵ +hyOc|5
} ^m qEKy<
//int [] counts = ps.executeBatch();⑶ JusU5 e|
conn.commit(); }s~c(sL?;
}catch(Exception e){ Y sM*d
e.printStackTrace(); 6cH8Jr _
} finally{ ORExI.<`W
try{ }t H$:Z
if(ps!=null) { 0pZvW
ps.clearParameters(); VXeO}>2S
ps.close(); &9yZfp
ps=null; p#@ #$u-
} Cr.YSWg)4
}catch(SQLException e){} KF.{r
DBUtils.closeConnection(conn); 4{P+p!4
} y\?ey'o
} f"ezmZI
public long getLast(){ n|i:4D
return lastExecuteTime; R/vHq36d
} RzEzNV
public void run(){ 6Tl6A>%s
long now = System.currentTimeMillis(); GKBoSSnV&
if ((now - lastExecuteTime) > executeSep) { A8)4nOXM
//System.out.print("lastExecuteTime:"+lastExecuteTime); qe0 D[L
//System.out.print(" now:"+now+"\n"); M8/a laoT
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); 76nH)^%l<
lastExecuteTime=now; ~YYnn7)
executeUpdate(); '75T2Ud
} i>m%hbAk
else{ %*
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//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); KgL!~J
} q/i2o[f'n
} b($hp%+yJ
} -#v~;Ci
//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 Vb0T)C
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类写好了,下面是在JSP中如下调用。 :`bC3Mr
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<% gmGK3am
CountBean cb=new CountBean(); $Z]&3VxxY
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); "=h1gql'
CountCache.add(cb); Xg)8}
out.print(CountCache.list.size()+"<br>"); KkJqqO"EL
CountControl c=new CountControl(); P?0X az
c.run(); <Ky-3:pxeM
out.print(CountCache.list.size()+"<br>"); WZ CI*'
%>