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: fDq,
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CountBean.java u0$7k9mE
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/* HH6b{f@^
* CountData.java }eb%"ZH4|
* w0~iGr}P
* Created on 2007年1月1日, 下午4:44 k`js~/Xv
* 0[D5]mcv
* To change this template, choose Tools | Options and locate the template under )T#;1qNB
* the Source Creation and Management node. Right-click the template and choose ?9X#{p>q
* Open. You can then make changes to the template in the Source Editor. c
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*/ %e7{ke}r
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package com.tot.count; iCN@G&rVw
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/** U^Z[6u
* 0s0[U
* @author 5HG 7M&_
*/ .mDqZOpf=4
public class CountBean { o;Zoj}
private String countType; ,-CDF)~G=3
int countId; vyV n5s
/** Creates a new instance of CountData */ RYE::[O7
public CountBean() {} $},:z]%D
public void setCountType(String countTypes){ TFxb\
this.countType=countTypes; p{Pa(Z]G
} B<1*p,z
public void setCountId(int countIds){ A&9l|b-"
this.countId=countIds; ~J<bwF
} O%o#CBf0
public String getCountType(){ NG'VlT
return countType; ErESk"2t
} EFql
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public int getCountId(){ ?xQlX%&`6
return countId; 77i |a]Kd
} no?)GQ
} pw>AQ
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CountCache.java ?%Y?z]L#
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/* ts;_T..L
* CountCache.java 7gVWu"
* )SA$hwR
* Created on 2007年1月1日, 下午5:01 c;U\nC<Y
* *~!xeL
* To change this template, choose Tools | Options and locate the template under +ZRsa`'^
* the Source Creation and Management node. Right-click the template and choose MP}H
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* Open. You can then make changes to the template in the Source Editor. pDkT_6Q
*/ %\~;I73
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package com.tot.count; m9G,%]4|
import java.util.*; o95O!5 hl
/** a
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* =~=/ d q
* @author $elrX-(vL
*/ R8'yQ#FVy
public class CountCache { {Y/|7Cl0
public static LinkedList list=new LinkedList(); eU%5CVH.v
/** Creates a new instance of CountCache */ u/.srK!K
public CountCache() {} qh7o;x~,
public static void add(CountBean cb){ c6c^9*,V
if(cb!=null){ ''5%5(Y.r
list.add(cb); ~Y'e1w$`
} m6;Xo}^w
} ~|uCZ.;o
} cJA:vHyw
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CountControl.java rB4#}+Uq
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/* ?>%u[g
* CountThread.java k5/nAaiVE
* %+I(S`}
* Created on 2007年1月1日, 下午4:57 k2t?e:)3zr
* w:Lu
* To change this template, choose Tools | Options and locate the template under zl:
u@!'
* the Source Creation and Management node. Right-click the template and choose izC>-
* Open. You can then make changes to the template in the Source Editor. LpmspIPvf
*/ 9d{W/t?NH
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package com.tot.count; Q%eBm_r;
import tot.db.DBUtils; ^1~/FU
import java.sql.*; pM46I"
/** !r
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* Hzj*X}X#K
* @author $AXz/fGV
*/ %x927I>
public class CountControl{ O]Kb~jkd
private static long lastExecuteTime=0;//上次更新时间 }TF<C!]
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 6U&Uyd)
/** Creates a new instance of CountThread */ z!3Z^d`
public CountControl() {} rmabm\QY
public synchronized void executeUpdate(){ %'=oMbi>i4
Connection conn=null; Qy70/on9
PreparedStatement ps=null; VuPET
try{ dt \O7Rjw8
conn = DBUtils.getConnection(); <oXsn.'\
conn.setAutoCommit(false); i3%~Gc63
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); ~qqtFjlG^
for(int i=0;i<CountCache.list.size();i++){ +%<Jr<~W
CountBean cb=(CountBean)CountCache.list.getFirst(); ;9I#>u
CountCache.list.removeFirst(); v
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ps.setInt(1, cb.getCountId()); DY07?x7
ps.executeUpdate();⑴ O,>&w5
//ps.addBatch();⑵ )/U1; O
} IL\mFjZ'
//int [] counts = ps.executeBatch();⑶ A0]o/IBz
conn.commit(); Tb)x8-0
}catch(Exception e){ {30<Vc=
e.printStackTrace(); YSwD#jO0
} finally{ =#^dG''*"
try{ PaDT)RrEM
if(ps!=null) { 0iL8i#y*
ps.clearParameters(); FRg6-G/S
ps.close(); )F$Stg3e
ps=null; 41zeN++
} uc<@
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}catch(SQLException e){} p!a%*LfND
DBUtils.closeConnection(conn); xsTxc&0^
} As\5Ze9|
} c:6w >:
public long getLast(){ qnS7z%H8
return lastExecuteTime; IY19G U9
} Kulg84<AwM
public void run(){ B.G!7>=
long now = System.currentTimeMillis(); f2u2Ns0Ym
if ((now - lastExecuteTime) > executeSep) { \\lC"Z#J`
//System.out.print("lastExecuteTime:"+lastExecuteTime); R:xmcUq}
(
//System.out.print(" now:"+now+"\n");
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// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); .Ep3~9TBW
lastExecuteTime=now; lC4By,1*
executeUpdate(); -Q@d
} :$tW9*\KY
else{ "n
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//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); G6,8Xwk
} MYPcH\K$h
} "pPNlV]UA^
} ye%F <:O7
//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 e)xWQ=,C
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类写好了,下面是在JSP中如下调用。 S|J8:-
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<% IYO,/ kbf
CountBean cb=new CountBean(); V[mQ;:=
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); etoE$2c
CountCache.add(cb); iN*>Z(b"
out.print(CountCache.list.size()+"<br>"); PGKXzp'
CountControl c=new CountControl(); 1A)~Y
c.run(); B1M/5cr.
out.print(CountCache.list.size()+"<br>"); FSmi.7
%>