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: U0Y;*_>4
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CountBean.java 1JIo,7
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/* 1Y-m=~J7
* CountData.java 8a;I,DK=j
* w>q:&Q
* Created on 2007年1月1日, 下午4:44 qf7oG0
* .1&~@e%=-
* To change this template, choose Tools | Options and locate the template under _ `RCY^t
* the Source Creation and Management node. Right-click the template and choose 4R~f
* Open. You can then make changes to the template in the Source Editor. *<[Nvk^
*/ yl=_ /'*
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package com.tot.count; tL;!!vg#V
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/** d\R]>
* [=
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* @author
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*/ }c"1;C&{
public class CountBean { ,bQbj7
private String countType; +@QN)ZwVy
int countId; 6Wm`Vj(s
/** Creates a new instance of CountData */ :RH0.5)
public CountBean() {} DeAi'"&
public void setCountType(String countTypes){ BJdH2qREN
this.countType=countTypes; kYVn4Wq
} soH
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public void setCountId(int countIds){ 0(Hhb#WDh\
this.countId=countIds; _7O;ED+
} I\BcG(hlJ
public String getCountType(){ GomTec9.
return countType; 99\;jz7
} ?ep'R&NV
public int getCountId(){ F>0[v|LG
return countId;
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} h#o3qY
} ]7d~,<3R
Kc>C$}/}$
CountCache.java x1$:u6YD22
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/* 4r&S&^
* CountCache.java KVvzVQ1
* h27awO
Q
* Created on 2007年1月1日, 下午5:01 33{(IzL0
* TH`zp]0
* To change this template, choose Tools | Options and locate the template under _ 2WG6y;
* the Source Creation and Management node. Right-click the template and choose |7K[+aK
* Open. You can then make changes to the template in the Source Editor. qNLG- m,n<
*/ ~1NK@=7T
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package com.tot.count; X/
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import java.util.*; rl\$a2_+
/** q\B048~KK
* [Ipg",Su;f
* @author r@2{>j8
*/ LxM.z1
public class CountCache { 6evW
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public static LinkedList list=new LinkedList(); R3G+tE/Y
/** Creates a new instance of CountCache */ Q}a,+*N.
public CountCache() {} @wy&Z
public static void add(CountBean cb){ -7^A_!.
if(cb!=null){ :%!}%fkxH
list.add(cb); jAa{;p"jU
} 8fn7!
} A?DgeSm
} nTJ-1A7EP
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CountControl.java \WDL?(G<
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/* /-#1ys#F=
* CountThread.java )w{bT]
* ^l UV^%f
* Created on 2007年1月1日, 下午4:57 !s>AVV$;0
* !T((d7;
* To change this template, choose Tools | Options and locate the template under 4>uy+"8PO
* the Source Creation and Management node. Right-click the template and choose 6N{Vcfq
* Open. You can then make changes to the template in the Source Editor. P <$)v5f
*/ Wz}8O]#/.
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package com.tot.count; qfO=_z ES
import tot.db.DBUtils; ^1a/)Be{_
import java.sql.*; PY4RwN
/** ad\?@>[I
* ^V
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* @author 6I$laHx?
*/ !besMZ
public class CountControl{ NZJ:@J=-
private static long lastExecuteTime=0;//上次更新时间 LqH<HGMFD
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 2k
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/** Creates a new instance of CountThread */ ^4+ew>BLSv
public CountControl() {} ;g3z?Uz)
public synchronized void executeUpdate(){ d},IQ,Az:Z
Connection conn=null; lZY0A#
PreparedStatement ps=null; *h<=
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try{ J3]!<v=
conn = DBUtils.getConnection(); V~Zi #o
conn.setAutoCommit(false); ]x8_f6;D
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); h,Y!d]2w
for(int i=0;i<CountCache.list.size();i++){ Quc,,#u
CountBean cb=(CountBean)CountCache.list.getFirst(); yGNZw7^(
CountCache.list.removeFirst(); uCc.dluU
ps.setInt(1, cb.getCountId()); ;XJK*QDN
ps.executeUpdate();⑴ rjmKe*_1V
//ps.addBatch();⑵ j>2Jw'l;?
} jWn!96NhlL
//int [] counts = ps.executeBatch();⑶ SIJ:[=5!7
conn.commit(); IL:d`Kbqf
}catch(Exception e){ xiu?BP?V
e.printStackTrace(); b`NXe7A
} finally{ kOe%w-_
try{ +d[A'&"
if(ps!=null) { *]ROUk@K=
ps.clearParameters(); ?_\t7f
ps.close(); j\^0BTZ
ps=null; Oz\mIVC#
} !]%M
}catch(SQLException e){} wq|~[+y
DBUtils.closeConnection(conn); RL|13CG OP
} O*hd@2hd
} xvZNshkpAX
public long getLast(){ qf/1a CQiP
return lastExecuteTime; Uoskfm
} D;f[7Cac
public void run(){ \hjGw,d
long now = System.currentTimeMillis(); 16iymiLz&
if ((now - lastExecuteTime) > executeSep) { !Gv*iWg
//System.out.print("lastExecuteTime:"+lastExecuteTime); _(CuuP$`I
//System.out.print(" now:"+now+"\n"); Q^^.@FU"x
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); \5+?wpH
lastExecuteTime=now; k,EI+lC X
executeUpdate(); {U$qxC]M
} v&6=(k{E@R
else{ -mSiZ
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); 8+m[ %5lu
} _eB?G
} f@ &?K<
} Rw]4/
//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 4_CV.?
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类写好了,下面是在JSP中如下调用。 87/!u]q
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<% '64&'.{#>r
CountBean cb=new CountBean(); >28.^\?H4
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); 4$~]t:n
CountCache.add(cb); RwH<JaL:
out.print(CountCache.list.size()+"<br>"); |{#=#3X
CountControl c=new CountControl(); T5mdC
c.run(); .YvE
out.print(CountCache.list.size()+"<br>"); R3MbTg
%>