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: __3s3YG
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CountBean.java G2 E4
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/* Wq+a5[3"
* CountData.java wm'a)B?
* m\0Xh*
* Created on 2007年1月1日, 下午4:44 tbH`VD"u
* zc`gm~@
* To change this template, choose Tools | Options and locate the template under -J06H&/k
* the Source Creation and Management node. Right-click the template and choose X0}+X'3
* Open. You can then make changes to the template in the Source Editor. 6dNW2_
*/ 6H #4iMeh
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package com.tot.count; pGsk[.
k6}M7&nY
/** *K57($F
* TI<?h(*R_
* @author Q|6lp
*/ ]U,c`?[7#
public class CountBean { X%Lhu6F
private String countType; t)i{=8rq
int countId; $M0F~x
/** Creates a new instance of CountData */ UZV\]Y
public CountBean() {} qdOUvf
public void setCountType(String countTypes){ _<8~CWo:
this.countType=countTypes; <73dXTZ0
} \C&[BQ\
public void setCountId(int countIds){ OpNxd]"T
this.countId=countIds; f i_'Ny>#
} 38 -vt,|
public String getCountType(){ eXYf"hU,
return countType; TdCC,/c3
} B1U<m=Y
public int getCountId(){ sU=7)*$
return countId; ZHN@&Gg6)
} %3:[0o={d
} J-k/#A4o
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CountCache.java Y6Mp[=
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/* vT&)
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* CountCache.java auai@)v6
* ;usR=i36b
* Created on 2007年1月1日, 下午5:01 `q$a
p$?
* YaT6vSz
* To change this template, choose Tools | Options and locate the template under 6z'3e\x
* the Source Creation and Management node. Right-click the template and choose Qf
.ASC
* Open. You can then make changes to the template in the Source Editor. o?O> pK
*/ #3_t}<fX
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package com.tot.count; XzD+#+By
import java.util.*; Q`B K
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/** mWP1mc:M(
* '|
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* @author <Rb[0E$
*/ &<>NP?j}
public class CountCache { XZ&cTjNB&
public static LinkedList list=new LinkedList(); ^aONuG9
/** Creates a new instance of CountCache */ }ZKG-~
public CountCache() {} .*k$abb
public static void add(CountBean cb){ ~x-v%x6
if(cb!=null){ I"hlLP
list.add(cb); yW)&jZb"(
} 99YgQ Y]HO
} S%p.|!
} Ds<~JfVl
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CountControl.java $[xS>iuD
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/* 49Q
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* CountThread.java q(9S4F
* +td]g9Ie
* Created on 2007年1月1日, 下午4:57 %ZR<z$
* gy*c$[NS$
* To change this template, choose Tools | Options and locate the template under %jErLg
* the Source Creation and Management node. Right-click the template and choose 8JFvz(SK>
* Open. You can then make changes to the template in the Source Editor. 4/?@ %
*/ ecsQshR
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package com.tot.count; |6O7_U#q
import tot.db.DBUtils; NE)Yd7m-
import java.sql.*; 5I6u 2k3
/** |\<L7|hb9
* Errs6
* @author crbph.0
*/ /=K(5Xd
public class CountControl{ G&z^AV
private static long lastExecuteTime=0;//上次更新时间 /_D_W,#P
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 3Ow bU
/** Creates a new instance of CountThread */ t8ZzBD!dP
public CountControl() {} f6])M)
public synchronized void executeUpdate(){ 8svN*`[
Connection conn=null; oB$c-!&
PreparedStatement ps=null; \n<9R8g5
try{ mFgrT
conn = DBUtils.getConnection(); Z'!i"Jzq|{
conn.setAutoCommit(false); ?_t_rF(?6
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); r T"3^,,
for(int i=0;i<CountCache.list.size();i++){ kQw%Wpuq[/
CountBean cb=(CountBean)CountCache.list.getFirst(); V~
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CountCache.list.removeFirst(); NyR,@n1
ps.setInt(1, cb.getCountId()); H{et2J<H
ps.executeUpdate();⑴ ]J^/`gc
//ps.addBatch();⑵ { u %xc"0y
} %}}?Y`/W)
//int [] counts = ps.executeBatch();⑶ x+8%4]u`
conn.commit(); p~3 (nk<+
}catch(Exception e){ C7=N`s}
e.printStackTrace(); ,.z?=]'en
} finally{ NA!?.zn
try{ ;-Ki`x.oJ
if(ps!=null) { ~Z:)Y*
ps.clearParameters(); ufn%sA
ps.close(); N#p%^GH
ps=null; \ OW.?1d
} {WvYb,
}catch(SQLException e){} {`ByZB
DBUtils.closeConnection(conn); hlBMRx49
} ,}:}"cl
} *_sSM+S
public long getLast(){ dlRTxb^Y>u
return lastExecuteTime; .x'?&7#(
} h7kn
>q;
public void run(){ Vj[hT~{f
long now = System.currentTimeMillis(); 'mTQ=1
if ((now - lastExecuteTime) > executeSep) { _ -|+k
//System.out.print("lastExecuteTime:"+lastExecuteTime); &d_2WQ}
//System.out.print(" now:"+now+"\n"); sH.,O9'r
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); JLak>MS
lastExecuteTime=now; G Ml JM
executeUpdate(); 8gxo{<,9
} |)y-EBZe\"
else{ Y~k,AJ{ ^
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); &)izh) FA
} _%wB*u,X
} `O]$FpO
} <<PXh&wu0
//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 J-z<&9
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类写好了,下面是在JSP中如下调用。 3Dx@rW\
-
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<% AfpC >>=@
CountBean cb=new CountBean(); NXMZTZpB7
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); O$7cN\Z
CountCache.add(cb); zSagsH |W
out.print(CountCache.list.size()+"<br>"); *Ksk1T+>
CountControl c=new CountControl(); '<U4D
c.run(); pv,z$3Q
out.print(CountCache.list.size()+"<br>"); *RmD%[f
%>