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: !&`}]qQZ
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CountBean.java ] *-;' *
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/* :)p)=c8%
* CountData.java #, Q}NO#vT
* I1)-,/nEjg
* Created on 2007年1月1日, 下午4:44 _1sMY hI
* 7qg<[
* To change this template, choose Tools | Options and locate the template under
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* the Source Creation and Management node. Right-click the template and choose q_T]9d
* Open. You can then make changes to the template in the Source Editor. *bA+]&dj\
*/ fxDj+Q1p
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package com.tot.count; \+k, :8s/
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/** ;1W6"3t-Y
* 5"JU?e59M
* @author ja[OcR-tX
*/ p jKt:R}
public class CountBean { hq<5lE^
private String countType; (0i'Nb"
int countId; ]@X{dc
/** Creates a new instance of CountData */ vv+D*e&<
public CountBean() {} NZLXN
public void setCountType(String countTypes){ <jeh`g
this.countType=countTypes; =m}TU)4.
} pW\z\o/2
public void setCountId(int countIds){ #{!O,`qD
this.countId=countIds; v f`9*x F
} ?g2zmI!U
public String getCountType(){ Xv0F:1
return countType; Sx8l<X
} S5N@\ x
public int getCountId(){ -!cIesK;<
return countId; =3*Jj`AV
} u4YM^* S.
} o{V#f_o
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CountCache.java 6xHi\L
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/* iZQ\
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* CountCache.java $A`xhh[
* iJ)0Y~
* Created on 2007年1月1日, 下午5:01 cC%j!8!
* "u;YI=+
* To change this template, choose Tools | Options and locate the template under -#aZF2z
* the Source Creation and Management node. Right-click the template and choose LeSHRoD
* Open. You can then make changes to the template in the Source Editor. !hCS#'
*/ Z:@6Lv?CN
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package com.tot.count; [ ?iqqG.
import java.util.*; DLi?'K3t
/** t?{B_Bf
* /b#q*x-b
* @author T C8`JU=wV
*/ )~V}oKk0t
public class CountCache { !
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public static LinkedList list=new LinkedList(); (#o t^
/** Creates a new instance of CountCache */ Uk,g> LG
public CountCache() {} q[ULGv
public static void add(CountBean cb){ Uoji@
if(cb!=null){ Ox qguT,
list.add(cb); (a.1M8v+Sg
} MzzKJ;wbC6
} d~@q%-`lA
} d(7NO;S8
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CountControl.java ^Kqf~yS%
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/* `~h4D(n`
* CountThread.java S~)w\(r
* +xp]:h|
* Created on 2007年1月1日, 下午4:57 40#9]=;}
* :#u}.G
* To change this template, choose Tools | Options and locate the template under 2z_2.0/3
* the Source Creation and Management node. Right-click the template and choose %NajFjBI
* Open. You can then make changes to the template in the Source Editor. CzVmNy)kl
*/ nY_?Jq
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package com.tot.count; f:woP7FP
import tot.db.DBUtils; uzBz}<M=
import java.sql.*; 3yV'XxC
/** T_;]fPajjD
* Y3',"
* @author OgCy4_a[f
*/ ".U^ifF
public class CountControl{ 'bu )M1OLi
private static long lastExecuteTime=0;//上次更新时间 W5pb;74|
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 osHCg
/** Creates a new instance of CountThread */ \we\0@v
public CountControl() {} |L::bx(
public synchronized void executeUpdate(){ k< j"~S1
Connection conn=null; edvFQ#,d
PreparedStatement ps=null; OqUr9?+
try{ L":bI&V?:
conn = DBUtils.getConnection(); !EBY@ Y1
conn.setAutoCommit(false); SJ?)%[(T
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); \Kavw
for(int i=0;i<CountCache.list.size();i++){ iL]'y\?lv
CountBean cb=(CountBean)CountCache.list.getFirst(); ~i~%~doa
CountCache.list.removeFirst(); r&3pM2Da}
ps.setInt(1, cb.getCountId()); gfa[4
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ps.executeUpdate();⑴ q]% T:A=
//ps.addBatch();⑵ 6^)}PX= *
} Sq2P-y!w
//int [] counts = ps.executeBatch();⑶ 9X}I>
conn.commit(); LT@OWH
}catch(Exception e){ ;_?MX/w|&
e.printStackTrace(); X/0v'N
} finally{ sLL7]m}
try{
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if(ps!=null) { HMGB>
ps.clearParameters(); K>/%X!RW
ps.close(); K^l:MxO-X
ps=null; ,&^3Z
} tt_o$D~kg
}catch(SQLException e){} _BM4>r?\
DBUtils.closeConnection(conn); C.Uju`3
} #qBr/+b
} J([s5:.[
public long getLast(){ eU@Cr7@,|
return lastExecuteTime; N)2f7j4C&
} 9xI GV!
public void run(){ iBg3mc@OO
long now = System.currentTimeMillis(); p=Q0!!_r
if ((now - lastExecuteTime) > executeSep) { 3VO2,PCZ
//System.out.print("lastExecuteTime:"+lastExecuteTime); u+m,b76
//System.out.print(" now:"+now+"\n"); &[Xu!LP
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); ~uWOdm-"[
lastExecuteTime=now; A7_4.VH
executeUpdate(); tRb]7 z
} 1c4/}3*
else{
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//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); 'dG%oDHX]P
} y9H%
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} Ws U)Y&
} B!]2Se2G
//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 p{A}pnjf
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类写好了,下面是在JSP中如下调用。 &F
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<% c,MOv7{x_
CountBean cb=new CountBean(); B Xms;[
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); $``1PJoi
CountCache.add(cb); :$;Fhf<5
out.print(CountCache.list.size()+"<br>"); f
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CountControl c=new CountControl(); VZr>U*J[:
c.run(); SvM6iZ]
out.print(CountCache.list.size()+"<br>"); MB^~%uZ2K
%>