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: dI%ho<zm]
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CountBean.java +
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/* &fWC-|
* CountData.java u kZK*Y9P
* CadIux^
* Created on 2007年1月1日, 下午4:44 %xG<hNw/
* nh5=0{va|L
* To change this template, choose Tools | Options and locate the template under _izjvg
* the Source Creation and Management node. Right-click the template and choose g] }!
* Open. You can then make changes to the template in the Source Editor. D_JGbNigA
*/ {47l1wV]
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package com.tot.count; GH-Fqz
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/** !
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* 9_jiUZFje
* @author M&29J
*/ 3imsIBr
public class CountBean { X<C fy
private String countType; s !2Iui
@
int countId; SJh~4R\
/** Creates a new instance of CountData */ Hd\oV^>
public CountBean() {} _6,\;"it?8
public void setCountType(String countTypes){ w|S b`eR
this.countType=countTypes; 3<M yb
} Z : xb8]y
public void setCountId(int countIds){ G'}N ?8s1
this.countId=countIds; U?{oxy_[ 2
} Wu|MNB?M
public String getCountType(){ KN657 |f
return countType; un~`|
} l5VRdZ4Uf
public int getCountId(){ Q8h0.(#-
return countId; =. \hCgq
} &k_*Y-l7]
} umq6X8K
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CountCache.java f
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/* o/VT"cT
* CountCache.java Z:N;>.3i
* aZ_3@I{d`
* Created on 2007年1月1日, 下午5:01 f sh9-iY8e
* lkJxb~S
* To change this template, choose Tools | Options and locate the template under C"**>OGe
* the Source Creation and Management node. Right-click the template and choose +jwk4BU
* Open. You can then make changes to the template in the Source Editor. N*&T)a
*/ \ HUDZ2 s
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package com.tot.count; ]4[%Sv6]G
import java.util.*; 2#^g] o-N
/** _z BfNz9D
* Q
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* @author h0k?(O
*/ ;Bz|hB{
public class CountCache { c;X,-Q9
public static LinkedList list=new LinkedList(); (2>q
/** Creates a new instance of CountCache */ vWESu4W`L
public CountCache() {} ~!PWJ~U
public static void add(CountBean cb){ L YB@L06a
if(cb!=null){ EZI#CLT[
list.add(cb); $<2d|;7r
} SZ[?2z
} UxHI6,b
} SDE+"MjBY
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CountControl.java #'>)?]tn
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/* |J:r]);@K
* CountThread.java #CI0G
* X,3\c:
* Created on 2007年1月1日, 下午4:57 FA{Q6fi:2
* :X'B K4EN
* To change this template, choose Tools | Options and locate the template under 9^n0<(99b
* the Source Creation and Management node. Right-click the template and choose ]*k ~jY,
* Open. You can then make changes to the template in the Source Editor. .4"BN<9
*/ D>W&#A8&y
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package com.tot.count; \yw5`5g
import tot.db.DBUtils; %Y;^$%X%_
import java.sql.*; d1c+Ii%
/** X=m^+%iD
* JHm Pa
* @author $},XRo&R
*/ }`QZV_
public class CountControl{ :ZB.I(v
private static long lastExecuteTime=0;//上次更新时间 `{>/'o
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 `|AH3v1
/** Creates a new instance of CountThread */ tR<#CCtRp'
public CountControl() {} ."BXA8c;A
public synchronized void executeUpdate(){ juF=ZW%i
Connection conn=null; ^ /G ;
PreparedStatement ps=null; d-Z2-89K
try{ +VW8{=$
conn = DBUtils.getConnection(); jG{?>^
conn.setAutoCommit(false); 08^f|K
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); `!I/6d?A
for(int i=0;i<CountCache.list.size();i++){ rBQ<5.
CountBean cb=(CountBean)CountCache.list.getFirst(); U@yhFj_y
CountCache.list.removeFirst(); ~%h
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ps.setInt(1, cb.getCountId()); |?^qsnB
ps.executeUpdate();⑴ A. tGr(r
//ps.addBatch();⑵ }ixCbuD
} z{1A x
//int [] counts = ps.executeBatch();⑶ U&R)a|
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conn.commit(); \VOv&s;h
}catch(Exception e){ viYrPhH+z
e.printStackTrace(); YfT
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} finally{ FT6C KsM"
try{ b~tu;:
if(ps!=null) { V~/@KU8cH
ps.clearParameters(); '9.@r\g
ps.close(); M"s:*c_6
ps=null; iOv>g-t:
} ue7D'
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}catch(SQLException e){} \Q}Y"oq
DBUtils.closeConnection(conn); (#>X*~6
} FywX
} O-p`9(_m
public long getLast(){ DN=W2MEfc
return lastExecuteTime; |gxPuAXa)
} tF/Ni*\^rV
public void run(){ # =y)Wuo=
long now = System.currentTimeMillis(); ESoC7d&.K{
if ((now - lastExecuteTime) > executeSep) { PDS( /x&
//System.out.print("lastExecuteTime:"+lastExecuteTime); 7@gH{p1
//System.out.print(" now:"+now+"\n"); Q wG_-
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); ZEDvY=@a
lastExecuteTime=now; q+8de_"]
executeUpdate(); #Pd__NV"\
} *74/I>i
else{ 19O
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); b#6mUl2
} ;J+iwS*Z
} s Adb0 A
} *^G,
//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 kzCJs
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类写好了,下面是在JSP中如下调用。 .3_u5N|[=W
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<% t D
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CountBean cb=new CountBean(); 1I'Q{X&B
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); OYWHiXE6]
CountCache.add(cb); _fn7-&6
out.print(CountCache.list.size()+"<br>"); *mj=kJ7(
CountControl c=new CountControl(); 5-fASN.Lx
c.run(); :!CnGKgt
out.print(CountCache.list.size()+"<br>"); #=)>,6Zw
%>