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: L8n|m!MOD
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CountBean.java _aMF?Pj~m
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/* -{_PuJ "
* CountData.java !%>7Dw(kt
* LIdF 0
* Created on 2007年1月1日, 下午4:44 Hr4}3.8
* O1kl70,`R
* To change this template, choose Tools | Options and locate the template under J.
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* the Source Creation and Management node. Right-click the template and choose IO> yIU[
* Open. You can then make changes to the template in the Source Editor. GH
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*/ *owU)
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package com.tot.count; WjjB<YKzF
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/** i@CxI<1'
* QdC<Sk!G
* @author a}uSm/S
*/ .[ mRM
public class CountBean { *9i{,I@
private String countType; KGpA2Nx
int countId; s9d_GhT%-
/** Creates a new instance of CountData */ 4Xv*wB1
public CountBean() {} KY N0
public void setCountType(String countTypes){ IIqUZJ
this.countType=countTypes; &"q=5e2
} Q5_o/wk
public void setCountId(int countIds){ o`RKXfCq
this.countId=countIds; o?
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} 6`-jPR
public String getCountType(){ {zFMmPid
return countType; [fIg{Q
} 7[wieYj{
public int getCountId(){ yCX?!E;La
return countId; ,v&(Y Od
} 4Z,!zFS$`
} _-F s#f8
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CountCache.java x3krbUlx
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/* OUXR
* CountCache.java 188*XCtjQ9
* 5PnDN\
* Created on 2007年1月1日, 下午5:01 k;L6R!V
* :,I:usW"
* To change this template, choose Tools | Options and locate the template under !Rt>xD
* the Source Creation and Management node. Right-click the template and choose d^6M9lGU
* Open. You can then make changes to the template in the Source Editor. MqUH',\3
*/ 1!gbTeVlY
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package com.tot.count; !v0LBe4
import java.util.*; >dG[G>
/** C>w|a
* = 9]~yt
* @author )>- =R5ZV
*/ \'bzt"f$j
public class CountCache { eGHaY4|
public static LinkedList list=new LinkedList(); + ?!(G}5
/** Creates a new instance of CountCache */ 0K2`-mL
public CountCache() {} L,@lp
public static void add(CountBean cb){ xZv#Es%#
if(cb!=null){ ?3xzd P
list.add(cb); F@:'J\I}:
} DDH:)=;z
} nj53G67y
} Wiu"k%Qsh
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CountControl.java }AH]
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/* _f:W?$\ho
* CountThread.java 3Ims6I]
* #
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* Created on 2007年1月1日, 下午4:57 &pp|U}
* :[!j?)%>
* To change this template, choose Tools | Options and locate the template under ]P?vdgEM&
* the Source Creation and Management node. Right-click the template and choose C 6AUNRpl
* Open. You can then make changes to the template in the Source Editor. Z/;aT -N
*/ Nu7
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package com.tot.count; 9p2&)kb6
import tot.db.DBUtils; cjIh}:|'
import java.sql.*; {,~3.5u
/** 6f*CvW
* & 9 ?\b7
* @author w)Qp?k
d
*/ j^2wb+`
public class CountControl{ /RC7"QzL
private static long lastExecuteTime=0;//上次更新时间 qeZ? 7#Gf
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 46&/gehr
/** Creates a new instance of CountThread */ NPe%F+X
public CountControl() {} 4Wm@W E
public synchronized void executeUpdate(){ Tyf`j,=
Connection conn=null; 7VF LJrt
PreparedStatement ps=null; C-[eaHJ'$
try{ 'u b@]ru|
conn = DBUtils.getConnection(); $'hEz/
conn.setAutoCommit(false); :A'y+MnK<
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); =zKM=qba
for(int i=0;i<CountCache.list.size();i++){ =$Nq
CountBean cb=(CountBean)CountCache.list.getFirst(); e;}7G
CountCache.list.removeFirst(); q(2'\ _`u
ps.setInt(1, cb.getCountId()); nK%LRcAs
ps.executeUpdate();⑴ R[x_j
//ps.addBatch();⑵ 4Ic*9t3
} ~1vDV>dpE
//int [] counts = ps.executeBatch();⑶ C&rkvM8
conn.commit();
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}catch(Exception e){ xx%j.zDI]
e.printStackTrace(); _8_R 1s
} finally{ 4u5-7[TZ
try{ ]F'e
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if(ps!=null) { @7j AL -
ps.clearParameters(); v<(
ps.close(); "mvt>X
ps=null; @'!SN\?W8
} DG:Z=LuJr
}catch(SQLException e){} l&Q`wR5e
DBUtils.closeConnection(conn); EGF '"L
} 76h ,]xi
} oEKvl3Hz_
public long getLast(){ =w
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return lastExecuteTime; l#Y,R 0
} XLOh7(
public void run(){ D2B%0sfl~
long now = System.currentTimeMillis();
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if ((now - lastExecuteTime) > executeSep) { X))/ m[_[
//System.out.print("lastExecuteTime:"+lastExecuteTime); <s<n
//System.out.print(" now:"+now+"\n"); KEjWRwN
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); x Bi' X
lastExecuteTime=now; .MoU1n{Yc
executeUpdate(); GM f
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} nwRc%C``UK
else{ * kDC liL
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); #-i>;Rt
} qL3;}R
} !/i{l
} j0evq+
//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 ;LSANr&
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类写好了,下面是在JSP中如下调用。 ywm8N%]v
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<% SdxDa
CountBean cb=new CountBean(); 0e ~JMUb
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); f=gW]x7'R+
CountCache.add(cb); J({Xg?
out.print(CountCache.list.size()+"<br>"); ']z{{UNUN
CountControl c=new CountControl(); V>-e y9Q\
c.run(); &n}f?
out.print(CountCache.list.size()+"<br>"); `l){!rg8IC
%>