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: i+< v7?:`#
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CountBean.java Kng=v~)N'
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/* K ;]dZ8
* CountData.java yV(9@lj3;
* e6tU8`z
* Created on 2007年1月1日, 下午4:44
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* T5e#Ll/
* To change this template, choose Tools | Options and locate the template under 2_o\Wor#
* the Source Creation and Management node. Right-click the template and choose 0aI@m
* Open. You can then make changes to the template in the Source Editor. <SOG?Lh~
*/ O;McPw<&\:
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package com.tot.count; z8%qCq
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/** MtF0/aT
* F2_'U' a
* @author J kAd3ls
*/ f}4A,%:1
public class CountBean { <RbfW'<G
private String countType; 7bRfkKD
int countId; .f;@OqU
/** Creates a new instance of CountData */ E4Ez)IaKyi
public CountBean() {} t0v>J9
public void setCountType(String countTypes){ p1i}fGS
this.countType=countTypes; _h,_HW)G
} ahCwA}
public void setCountId(int countIds){ Q8QB{*4
this.countId=countIds; 02%~HBS
} F^%\AA]8
public String getCountType(){ ?MmQ'1N
return countType; Mw-L?j0o[k
} 8\:>;XG6f
public int getCountId(){ _5(p=Zc
return countId; ?1Vx)j>|
} O{7#Xj
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} (18ZEKk
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CountCache.java _dCDT$^&r
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/* be]/ROP>H
* CountCache.java n@"<NKzh
* F`(;@LO
* Created on 2007年1月1日, 下午5:01 3$:F/H
* 'Z9UqEGV
* To change this template, choose Tools | Options and locate the template under '/9MN;_
* the Source Creation and Management node. Right-click the template and choose :AqtPV'
* Open. You can then make changes to the template in the Source Editor. g+QIhur
*/ 3="vOSJ6&
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package com.tot.count; hgE:2@
import java.util.*; )8}k.t>'s
/** @]}/vsI m
* 9xw"NcL
* @author >t'A1`W
*/ V:P]Ved
public class CountCache { /?XI,#j3kM
public static LinkedList list=new LinkedList(); Z(R0IW
/** Creates a new instance of CountCache */ Ars*H,9>e
public CountCache() {} QkHG`yW
public static void add(CountBean cb){ xE!0p EHd
if(cb!=null){ ,g*3u
list.add(cb); n4 N6]W\5
} w,R6:*p5
} t>*(v#WeZ
} 2|B@s3a
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CountControl.java )Td{}vbIh
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/* :5T=y @
* CountThread.java h>cjRH?e
* 2Kr>93O
* Created on 2007年1月1日, 下午4:57 2DJg__("
* :(yut
* To change this template, choose Tools | Options and locate the template under C|w<mryx
* the Source Creation and Management node. Right-click the template and choose {TJBB/B1
* Open. You can then make changes to the template in the Source Editor. Ya!e83-r
*/ O#O"]A
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package com.tot.count; '
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import tot.db.DBUtils; 98?O[=
import java.sql.*; NW3qs`$-(
/** R-OO1~W=
* i^A=nsD`
* @author WDV=]D/OE
*/ |r)QkxdU,
public class CountControl{ xWK/uE (
private static long lastExecuteTime=0;//上次更新时间 rbIYLVA+V
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 Y{#*;p*I
/** Creates a new instance of CountThread */ a;-%C{S9r
public CountControl() {} ~%M*@fm
public synchronized void executeUpdate(){ %N(>B_t\
Connection conn=null; z\8s |!
PreparedStatement ps=null; uW FyI"
try{ kw gLK@@%1
conn = DBUtils.getConnection(); UHU ,zgM
conn.setAutoCommit(false); R2C~.d_TDu
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); (&r`
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for(int i=0;i<CountCache.list.size();i++){ 'wMvO{}$
CountBean cb=(CountBean)CountCache.list.getFirst(); En\q. 3
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CountCache.list.removeFirst(); G{>PYLxOb
ps.setInt(1, cb.getCountId()); P?n4B \!
ps.executeUpdate();⑴ ^ACrWk~UY
//ps.addBatch();⑵ bqA`oRb\
} l`A&LQ[
//int [] counts = ps.executeBatch();⑶ Qy[S~D_
conn.commit(); *jPd=+d
}catch(Exception e){ dPf7o
e.printStackTrace(); /QVwZrch
} finally{ g"kI1^[nj
try{ !~R<Il|B
if(ps!=null) { e?B}^Dk0i
ps.clearParameters(); rKFnivGT
ps.close(); FkuD Gg~a
ps=null; K{`R`SXD
} B9$f y).Gp
}catch(SQLException e){} Tbv w?3
DBUtils.closeConnection(conn); Meep
} j%w^8}U>G
} ePJ_O~c
public long getLast(){ EU|IzUjFj|
return lastExecuteTime; 5p:BHw;%;
} -@`Ah|m@}
public void run(){ yZ)9Hd
long now = System.currentTimeMillis(); l:JVt`A4?
if ((now - lastExecuteTime) > executeSep) { (jj`}Qe3U
//System.out.print("lastExecuteTime:"+lastExecuteTime); cqJXZ.XC
//System.out.print(" now:"+now+"\n"); 8HJ,6L r;
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); i '*!c
lastExecuteTime=now; \O;/wf0Hg
executeUpdate(); 1i~q~O,
} e`LkCy[_
else{ Yk?q \1
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); %,HUn`
} W SxoGly
} MMpId
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} MusUgBQy
//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 6_u!{
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类写好了,下面是在JSP中如下调用。 ZN;ondp4
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<% [r3sk24
CountBean cb=new CountBean(); G6W|l2P!
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); N"G\H<n
CountCache.add(cb); Y%0rji
out.print(CountCache.list.size()+"<br>"); k+P3z&e
CountControl c=new CountControl(); ;|?_C8
c.run(); ,]: <l
out.print(CountCache.list.size()+"<br>"); :Rv+Bm
%>