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: E( h<$w8s
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CountBean.java gZEi]/8_
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/* .7
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* CountData.java *c)uGz'cD
* /1 RAAa
* Created on 2007年1月1日, 下午4:44 ex<O]kPFE
* gt\MS;jMa
* To change this template, choose Tools | Options and locate the template under :d8W+|1u
* the Source Creation and Management node. Right-click the template and choose {,cCEXag%
* Open. You can then make changes to the template in the Source Editor. k/03ZxC-
*/ )?2e
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package com.tot.count; )9S>ZZF
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/** z`6fotL
* L.T?}o
* @author Q`#4W3-,
*/ ?go:e#
public class CountBean { c!hwmy;
private String countType; O}[PJfvBHo
int countId; [I:KpAd/
/** Creates a new instance of CountData */ DOz\n|8S
public CountBean() {} ~w</!s
public void setCountType(String countTypes){ HK)cKzG[s!
this.countType=countTypes; {T'GQz+R"
} %hN.ktZ/s
public void setCountId(int countIds){ 4 V1bLm
this.countId=countIds; TrdZJ21#M
} {u[V{XIUh
public String getCountType(){ CAT.4GM
return countType; !vn1v)6
} >23-
public int getCountId(){ efG6v
return countId; ^>?CMcN4*
} AkU<g
} ?%O3Oi Xz
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CountCache.java _al|'obomy
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/* 7DKz;o
* CountCache.java )s9',4$eK<
* $DBGLmw
* Created on 2007年1月1日, 下午5:01 @FN*TJ
* ~dHM4lGY
* To change this template, choose Tools | Options and locate the template under |BZDhd9<{
* the Source Creation and Management node. Right-click the template and choose IkzTJ%>
* Open. You can then make changes to the template in the Source Editor. 'O6]0l
*/ Gq#~vr
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package com.tot.count; U6[ang'l
import java.util.*; ?4G|+yby
/** Zs2-u^3&
* I =Wc&1g
* @author %g]vxm5?
*/ zu2HH<E
public class CountCache { >%Ee#m
public static LinkedList list=new LinkedList(); >\<*4J$PZ
/** Creates a new instance of CountCache */ }]UB;id'
public CountCache() {} :
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public static void add(CountBean cb){ U"f??y%)
if(cb!=null){ fQnwy!-\
list.add(cb); mqfO4"lt
} c~<1':
} $[@0^IJq=K
} hIJ)MZU|
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CountControl.java 2eQdQwX
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/* %OcGdbs
* CountThread.java RE 3Z%;'
* (IbW;bV
* Created on 2007年1月1日, 下午4:57 [O
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* 9H]_4?aX
* To change this template, choose Tools | Options and locate the template under D~K;~nI
* the Source Creation and Management node. Right-click the template and choose 1on'^8]0
* Open. You can then make changes to the template in the Source Editor. s|bM%!$1
*/ ~F,
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package com.tot.count; '[ P}&<ie,
import tot.db.DBUtils; P
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import java.sql.*; mT*{-n_Zs
/** 1U\$iy8}
* G&eP5'B4i
* @author qu6DQ@
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*/ $trAC@3O@
public class CountControl{ 9=dkx^q
private static long lastExecuteTime=0;//上次更新时间 FZpKFsPx
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 9O,,m~B
/** Creates a new instance of CountThread */ Lb=W;9;
public CountControl() {} RBGlzk
public synchronized void executeUpdate(){ qBk``!|s]
Connection conn=null; oCi
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PreparedStatement ps=null; CPazEe1S
try{ BRG|Asg(
conn = DBUtils.getConnection(); L$v^afP?
conn.setAutoCommit(false); 1D([@)^
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); ~H@+D}J?
for(int i=0;i<CountCache.list.size();i++){ _q>SE1j+W=
CountBean cb=(CountBean)CountCache.list.getFirst(); Y^ve:Z
CountCache.list.removeFirst(); K%KZO`gO
ps.setInt(1, cb.getCountId()); H ;@!?I
ps.executeUpdate();⑴ y@ek=fT%4
//ps.addBatch();⑵ \6j^kY=
} 1ywU@].6J]
//int [] counts = ps.executeBatch();⑶ 0WxCSL$#I
conn.commit(); 0_<Nc/(P
}catch(Exception e){ @u4=e4eF`
e.printStackTrace(); ? S=W&
} finally{ ^gro=Bp(
try{ h=RDO
if(ps!=null) { YwT-T,oD
ps.clearParameters(); 5a8>g
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ps.close(); \Xg?Ug*9w
ps=null; )+O r
} Il~01|3+m
}catch(SQLException e){} =F%RLpNU4
DBUtils.closeConnection(conn); 2O""4_G
} M7y|EB))
} 1|y$~R.H
public long getLast(){ <ZPZk'53<f
return lastExecuteTime; +S {
} cHvF* A
public void run(){ T.?k>Ak
long now = System.currentTimeMillis(); (
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if ((now - lastExecuteTime) > executeSep) { uOk%AL>
//System.out.print("lastExecuteTime:"+lastExecuteTime); Mn^zYW|(
//System.out.print(" now:"+now+"\n"); f$xhb3Qn
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); +QqH}=
M
lastExecuteTime=now; Zy]s`aa
executeUpdate(); @]
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} ML!9:vz
else{ {/M\Q@j
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); 7|D|4!i2Y
} L-'k7?%(
} sB*o)8
} MR9/Y:Nm
//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 D,W\ gP/h%
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类写好了,下面是在JSP中如下调用。 Z(!pYhLq
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<% 0g(6r-2)7
CountBean cb=new CountBean(); [Z}B"
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); u35q,u=I
CountCache.add(cb); 3B18dv,V
out.print(CountCache.list.size()+"<br>"); Q9y*:
CountControl c=new CountControl(); EnCU4CU`
c.run(); t3F?>G#y
out.print(CountCache.list.size()+"<br>"); CI^|k/
%>