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: H{ $ yy)@F
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CountBean.java bQeYFY#^
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/* 34l=U?
* CountData.java D@ lJ^+
* .s9Iymz
* Created on 2007年1月1日, 下午4:44 $fn^i.
* 4C[gW
* To change this template, choose Tools | Options and locate the template under JC+VG;kcs
* the Source Creation and Management node. Right-click the template and choose w'eenIX^^
* Open. You can then make changes to the template in the Source Editor. QMsnfG
*/ 07MLK8jS
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package com.tot.count; u4nXK
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/** wvYxL
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* Bl1I "B
* @author W>Kwl*Cis"
*/
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public class CountBean { x$p\ocA
private String countType; J+4uUf/d!
int countId; ejQCMG7
/** Creates a new instance of CountData */ Z:OO|x
public CountBean() {} E:tUbWVp
public void setCountType(String countTypes){ ^49moC-
this.countType=countTypes; 8]L.E
} R.QcXz?d
public void setCountId(int countIds){ Eg:p_F*lr
this.countId=countIds; Y\=:j7'
} 3k(?`4JJ
public String getCountType(){ S`^W#,rj
return countType; t2gjhn^p
} e8# 3Y+Tc
public int getCountId(){ \r2qH0B
return countId; 2u:j6ic
} Ue7W&N^E
} .`p_vS9
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CountCache.java g:)vthOs
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/* e{O5y8,
* CountCache.java :Ry24X
* {V&7JZl,/
* Created on 2007年1月1日, 下午5:01 c%dy$mkqgK
* b(VU{cf2d
* To change this template, choose Tools | Options and locate the template under ~_&.A* Jh
* the Source Creation and Management node. Right-click the template and choose +!Ltn
* Open. You can then make changes to the template in the Source Editor. ig,|3(
*/ LKZI@i)
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package com.tot.count; QUDVsN#
import java.util.*; vB{b/xmah
/** ?uN(" I
* )-{~7@yqZ
* @author a8 1%M
*/ @rMW_7[y
public class CountCache { 9|`@czw
public static LinkedList list=new LinkedList(); #jJcgR<
/** Creates a new instance of CountCache */ MocH>^,
public CountCache() {} &1{k^>oz
public static void add(CountBean cb){ l1[IXw?
if(cb!=null){ ("6W.i>
list.add(cb); Y<+4>Eh
} yd~fC:_ ]
} t;]egk
} bij?q\
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CountControl.java 6~S0t1/t?
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/*
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* CountThread.java )8SP$
* {+:XVT_+
* Created on 2007年1月1日, 下午4:57 &>{>k<z
* m { fQL
* To change this template, choose Tools | Options and locate the template under ar|[D7Xrq\
* the Source Creation and Management node. Right-click the template and choose \gkajY-?
* Open. You can then make changes to the template in the Source Editor. yh:,[<q
*/ cZ >W8{G
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package com.tot.count; 3c3Z"JV
import tot.db.DBUtils; ^j %UZ
import java.sql.*; nS4S[|w"
/** q#`^EqtUF
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* @author
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*/ ArYF\7P
public class CountControl{ Z L</
private static long lastExecuteTime=0;//上次更新时间 ([*t.
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 DcA'{21
/** Creates a new instance of CountThread */ ~S6 {VK.
public CountControl() {} njMy&$6a##
public synchronized void executeUpdate(){ ~P_kr'o
Connection conn=null; P{eRDQ=
PreparedStatement ps=null; #pSOZX
try{ sCQup^\
conn = DBUtils.getConnection(); oNZW#<K
conn.setAutoCommit(false); [{F7Pc
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); c5e\ckqm^
for(int i=0;i<CountCache.list.size();i++){ S$52KOo
CountBean cb=(CountBean)CountCache.list.getFirst(); ]gksyxn3
CountCache.list.removeFirst(); ?8@*q6~8
ps.setInt(1, cb.getCountId()); C4tl4df9
ps.executeUpdate();⑴ E{s|#
//ps.addBatch();⑵ |vz;bJG
} zDyeAxh4
//int [] counts = ps.executeBatch();⑶ x Ui!|c
conn.commit(); (N|xDl&;
}catch(Exception e){ &o@5%Rz2/
e.printStackTrace(); k+$4?/A
} finally{ 8
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try{ 3gy;$}Lq T
if(ps!=null) { L0b]^_tI
ps.clearParameters(); }27Vh0v
ps.close(); %E"/]!}3
ps=null; "NH+qQhs
} :QV6z*#zD
}catch(SQLException e){} T zYgH
DBUtils.closeConnection(conn); gsWlTI
} -_DiD^UcXn
} ;}~Bv<#
public long getLast(){ YwWTv
return lastExecuteTime; }#*zjMOz
} Z'dI!8(Nf
public void run(){ sFCs_u1tNN
long now = System.currentTimeMillis(); j :Jdwf
if ((now - lastExecuteTime) > executeSep) { E)wT+\
//System.out.print("lastExecuteTime:"+lastExecuteTime); zl
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//System.out.print(" now:"+now+"\n"); ;n{j,HB
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); dG>Wu o
lastExecuteTime=now; 8/?uU]#Q
executeUpdate(); }|"*"kxi!
} `OReSg
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else{ Z?c=t-yqp
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); zMzf=~
} b%f2"e0g
} 1=5'R/k
} zRoEx1
//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 x ETVtq
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类写好了,下面是在JSP中如下调用。 zw0 r
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<% ;:\,x
CountBean cb=new CountBean(); -sH.yAvC6
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); k,iV$,[TF
CountCache.add(cb); +Y9D!=_lj
out.print(CountCache.list.size()+"<br>"); -_*XhD
CountControl c=new CountControl(); B
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c.run(); TgE.=` "7
out.print(CountCache.list.size()+"<br>"); f9XO9N,hE:
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