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: j{00iA}
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CountBean.java WqX#T
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/* %Q9
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* CountData.java NV 6kj=r
* EugQr<sM#
* Created on 2007年1月1日, 下午4:44 X=O}k&
* /5 rWcX
* To change this template, choose Tools | Options and locate the template under `NIc*B4q.
* the Source Creation and Management node. Right-click the template and choose gd~# uR\
* Open. You can then make changes to the template in the Source Editor. zrD];DP
*/ |DAe2RK
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package com.tot.count; 2$8#ePyq*
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/** 2
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* "vVL52HwB
* @author :2#8\7IU^'
*/ MRzrZZ%LQ
public class CountBean { Q"UWh~
private String countType; ^6*LuXPv
int countId; 2,.%]U
/** Creates a new instance of CountData */ TG ,T>'
public CountBean() {} 0Y7b$~n'Y
public void setCountType(String countTypes){ Xq"@Z
this.countType=countTypes; WR'm<u
} r?Y+TtF\e
public void setCountId(int countIds){ (x7AV$N
this.countId=countIds; P} =eR
} |)'gQvDM
public String getCountType(){ 5r1{l%?
return countType; 2p3ep,
} " jefB6k9h
public int getCountId(){ rG7S^,5o
return countId; !Gwf"-TQ
} >y<yFO{
} K}^Jf;
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CountCache.java S,&tKDJn
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/* iO^z7Y7
* CountCache.java &%YFO'>>}
* 4}nsW}jCc
* Created on 2007年1月1日, 下午5:01 jn+NX)9
* 2I!STP{ !l
* To change this template, choose Tools | Options and locate the template under `? ayc/TK
* the Source Creation and Management node. Right-click the template and choose 8ut:cCrmg
* Open. You can then make changes to the template in the Source Editor. b?&=gm%oU
*/ zPwU'TbF
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package com.tot.count; G/tah@N[7
import java.util.*; rSTc4m1R
/** 3wRk -sl
* 7 ky$9+~
* @author d~[^D<5,D
*/ |E+tQQr%'
public class CountCache { v] *(Wd~|
public static LinkedList list=new LinkedList(); FS.z lk\D=
/** Creates a new instance of CountCache */ _;*|"e@^
public CountCache() {} =}@m$g
public static void add(CountBean cb){ }hT1@I
if(cb!=null){ z!09vDB^
list.add(cb); '8g/^Y@
} k:(i sKIA
} B Z:H$v
} @&f3zq
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CountControl.java Ve<3XRq|8
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/* !A>VzW
* CountThread.java Y~=]RCg
* s
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* Created on 2007年1月1日, 下午4:57 A=X2zm>9
* {V&
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* To change this template, choose Tools | Options and locate the template under ,Mwyk1:xix
* the Source Creation and Management node. Right-click the template and choose M,Y lhL
* Open. You can then make changes to the template in the Source Editor. 3HsjF5?W
*/ ,6[}qw)*
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package com.tot.count; kqYvd]ss
import tot.db.DBUtils; , WF)GS|7V
import java.sql.*; PPCZT3c=
/** Uk5O9D0
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* 5- Q`v/w;
* @author H!dUQ
*/ MxiU-
public class CountControl{ ailje
private static long lastExecuteTime=0;//上次更新时间 dvUBuY^[
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 K`PmWxNPh
/** Creates a new instance of CountThread */ V'h
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public CountControl() {} 7#Qa/[? D
public synchronized void executeUpdate(){ W'{q
Connection conn=null; g%w@v$
PreparedStatement ps=null;
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try{ SfE^'G\
conn = DBUtils.getConnection(); W-Cf#o
conn.setAutoCommit(false); EXz5Rue
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ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); I>b-w;cC
for(int i=0;i<CountCache.list.size();i++){ qL^}t_>
CountBean cb=(CountBean)CountCache.list.getFirst(); W%]sI n
CountCache.list.removeFirst(); 6p/gvpZ
ps.setInt(1, cb.getCountId()); 7lpd$Y
ps.executeUpdate();⑴ aE^tc'h~
//ps.addBatch();⑵ ?v2OoNQ
} 3Lwl~h!
//int [] counts = ps.executeBatch();⑶ fM]McZ9)D
conn.commit(); ki6`d?
}catch(Exception e){ ~Z5?\a2Ld
e.printStackTrace(); H[ %Fo
} finally{ .kM74X=S
try{ to Ei4u)m
if(ps!=null) { (^g?/i1@d
ps.clearParameters(); !x. ^ya
ps.close(); 9E_C
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ps=null; 3uwZ#
} $ 1(u.Ud
}catch(SQLException e){} tkdhT8_
DBUtils.closeConnection(conn); JbYv <
} [|{yr
} d"78w-S
public long getLast(){ [~)i<V|qJ
return lastExecuteTime; 5| 2B@6-
} zY8"\ZB
public void run(){ ~MY7Ic%
long now = System.currentTimeMillis(); -"5x? \.{m
if ((now - lastExecuteTime) > executeSep) { o}5:vi]
//System.out.print("lastExecuteTime:"+lastExecuteTime); Yfy6o6*:
//System.out.print(" now:"+now+"\n"); $4kc i@.
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); XKp %7;
lastExecuteTime=now; yz-IZt(
executeUpdate(); sZ-]yr\E"
} uVqJl{e\
else{ ovCk:Vz
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); ,TU!W|($
} 1G|Q~%cv
} bl\44VK2'
} $X5~9s1Wl
//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 -mZo`
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类写好了,下面是在JSP中如下调用。 kETA3(h'
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<% <Q=ES,M
CountBean cb=new CountBean(); ^e8R43w:!
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); 5h[u2&;G
CountCache.add(cb); p)tac*US
out.print(CountCache.list.size()+"<br>"); QN-n9f8
CountControl c=new CountControl(); c}mJ6Pt
c.run(); :LVM'c62c>
out.print(CountCache.list.size()+"<br>"); &+`l
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