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: $MwBt
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CountBean.java \7*|u
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/* #\^=3A|b
* CountData.java phf{b+'#X
* ,VEE<*'X
* Created on 2007年1月1日, 下午4:44 ZX`x9/0&
* `5wiXsNjLY
* To change this template, choose Tools | Options and locate the template under w6X:39d
* the Source Creation and Management node. Right-click the template and choose ^9 LoxU-
* Open. You can then make changes to the template in the Source Editor. oA~0"}eS
*/ _/}$X"4
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package com.tot.count; %k['<BYG<
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/** Shy.:XI
* .$W}
* @author @sZ7Ka
*/ X@tA+
public class CountBean { F
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private String countType; ocK4Nxs
int countId; hFr+K1
/** Creates a new instance of CountData */ #rGCv~0*l
public CountBean() {} I ZLCwaW
public void setCountType(String countTypes){
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this.countType=countTypes; F02TM#Zi
} 3gVU#T[[
public void setCountId(int countIds){ +2 oZML
this.countId=countIds; C(B"@
} Q$]1juqg
public String getCountType(){ RfD#/G3|
return countType; t g-(e=S4P
} *!BQ1] G
public int getCountId(){ ;^0ok'P\~9
return countId; 047PlS
} .B2e$`s$
} M!!vr8}
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CountCache.java `fX\pOk~e
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/* 2W_[|.;'
* CountCache.java O NcLhwH
* _ eBNbO_J
* Created on 2007年1月1日, 下午5:01 \_R<Q?D+
* aBY&]6^-
* To change this template, choose Tools | Options and locate the template under SC2LY
* the Source Creation and Management node. Right-click the template and choose -#/DK
* Open. You can then make changes to the template in the Source Editor. ]:?S}DRG
*/ n[K%Xs)
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package com.tot.count; W1xPK*
import java.util.*; J>#yA0QD2
/** <zvtQ^{]
* fSVM[
* @author hslT49m>
*/ noa+h<vGb
public class CountCache { z@\mn
public static LinkedList list=new LinkedList(); vShB26b
/** Creates a new instance of CountCache */ =+T0[|gc(r
public CountCache() {} S[/udA
public static void add(CountBean cb){ %'e$N9zd
if(cb!=null){ 2|RoN)%
list.add(cb); F^!O\8PFd
} Zj ` ;IYFG
}
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} <_eEpG}9
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CountControl.java Ev [?5R
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/* <'sm($.2
* CountThread.java %_p]6doF
* !J<0.nO/:
* Created on 2007年1月1日, 下午4:57 :]Om4Q\-#
* eS
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* To change this template, choose Tools | Options and locate the template under upk_;ae
* the Source Creation and Management node. Right-click the template and choose jR\! 2!
* Open. You can then make changes to the template in the Source Editor. 40].:9VG
*/ T>#~.4A0
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package com.tot.count; bVN?7D(
import tot.db.DBUtils; _]Ob)RUVH
import java.sql.*; WpE"A
/** 'IIa,']H
* D5bi)@G7z
* @author `VGw5o
*/ Th\T$T`X$
public class CountControl{ '4u/ g
private static long lastExecuteTime=0;//上次更新时间 g;AW
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 d*k5h<jM
/** Creates a new instance of CountThread */ `uusUw-Gf
public CountControl() {} z+wegF
public synchronized void executeUpdate(){ c>/7E-T
Connection conn=null; lAC"7 Z?F
PreparedStatement ps=null;
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try{ T7/DH
conn = DBUtils.getConnection(); $;=?[Cn
conn.setAutoCommit(false); x]%,?Vd?
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); Gkfzb>_V]
for(int i=0;i<CountCache.list.size();i++){ ~/aCzx~
CountBean cb=(CountBean)CountCache.list.getFirst(); Oz]$zRu/0
CountCache.list.removeFirst(); +CSR!
ps.setInt(1, cb.getCountId()); .Sa=VC?EZ
ps.executeUpdate();⑴ 0Db=/sJ>
//ps.addBatch();⑵ R! X+-
} gCkR$.-E
//int [] counts = ps.executeBatch();⑶ &%/T4$'+Y+
conn.commit(); e F}KOOfC
}catch(Exception e){ Y@MxKK uj
e.printStackTrace(); UM21Cfqex
} finally{ kqo4
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try{ z/QYy)_j
if(ps!=null) { i7 YUyU
ps.clearParameters(); OuWRLcJ!
ps.close(); k_?OEkgUh
ps=null; \{a5]G(4s
} s)-bOZi
}catch(SQLException e){} ]uh/ !\
DBUtils.closeConnection(conn); 3N2d@R
} DOkuT/+
} BAi0w{
public long getLast(){ 6iEg]FI
return lastExecuteTime; @/$i
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} !>Q\Y`a,*
public void run(){ <W7WlT
long now = System.currentTimeMillis(); unz~vG1Tn
if ((now - lastExecuteTime) > executeSep) { xkSVD6Km
//System.out.print("lastExecuteTime:"+lastExecuteTime); YG0b*QBY~
//System.out.print(" now:"+now+"\n"); [Ran/D\.
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); uXUuA/O5-
lastExecuteTime=now; 7'{Vh{.
executeUpdate(); wr,+9uK
} D97 vfC
else{ >X"\+7bw
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); hPgYKa8u
} pSYEC,0B
} SsfC
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} #RSUChe7w
//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 DZH2U+K
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类写好了,下面是在JSP中如下调用。 Vl<7>
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<% $cm9xW&
CountBean cb=new CountBean(); F1M:"-bda
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); .We{W{
CountCache.add(cb); RVs=s}|>*
out.print(CountCache.list.size()+"<br>"); psz0q|
CountControl c=new CountControl(); :+
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c.run(); >$r o\/
out.print(CountCache.list.size()+"<br>"); Qr6PkHU
%>