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: DF&(8NoX~
WltQ63u
CountBean.java uF X#`^r`
O\
GEay2
/* l3{-z4mw
* CountData.java ?U%qPv:
* >1.X*gi?-
* Created on 2007年1月1日, 下午4:44 5-FQMXgThc
* ;@0;pY
* To change this template, choose Tools | Options and locate the template under `Syl:rU~y@
* the Source Creation and Management node. Right-click the template and choose Mc?Qx
* Open. You can then make changes to the template in the Source Editor. ^a/gBC82x
*/ ]MqMQLG0t
OsTc5K.U~
package com.tot.count; (j%~u&+-
7!evm;A
/** ntu5{L'8
* v3*_9e
* @author D.r<QO~6B
*/ 2+RUTOv/d
public class CountBean { VRVO-Sk
private String countType; M f}~{+
int countId; c_dVWh e
/** Creates a new instance of CountData */ zKyyU}LHH
public CountBean() {} b10cuy|a/X
public void setCountType(String countTypes){ ;d@#XIS&-(
this.countType=countTypes; 'S20\hwt-
} <kfnpB=
public void setCountId(int countIds){ ({ +!`}GY
this.countId=countIds; /?wtF4
} nyX2|m&
public String getCountType(){ FXpJqlhNv
return countType; TCMCK_SQL
}
+Te\H
public int getCountId(){ TeMHm?1^
return countId; b}2ED9HG\
} HNb/-e ,"
} S%$ }(
^8]NxV@l
CountCache.java )~&CvJ
aacpM[{f
/* L{#IT.
* CountCache.java %gInje
* /RG:W0=K
* Created on 2007年1月1日, 下午5:01 2\)xpOj
* mWv3!i;G<s
* To change this template, choose Tools | Options and locate the template under hM_lsc
* the Source Creation and Management node. Right-click the template and choose 0$(WlP|
* Open. You can then make changes to the template in the Source Editor. \/93Dz
*/ d}OTO10
_H9 MwJ
package com.tot.count; .fn\]rUv
import java.util.*; ;RH;OE,A
/** 2my_ ;!6T[
* FW;m\vu
* @author , |0}<%
*/ .14~J6
public class CountCache { #F:p-nOq
public static LinkedList list=new LinkedList(); ~Q*%DRd&Z-
/** Creates a new instance of CountCache */ u6J8"<
-W
public CountCache() {} '%>=ZhO
public static void add(CountBean cb){ W4t;{b
if(cb!=null){ 2_)\a(.Qu
list.add(cb); {WJ m
} G5{T5#
} xv46r=>
} O8f?; ]
m\;R2"H%
CountControl.java M+-*QyCFK
adlV!k7RG
/* r^2p*nr}
* CountThread.java "N;`1ce
* ?K1/ <PE+
* Created on 2007年1月1日, 下午4:57 "H2EL}3/]
* WEAT01
* To change this template, choose Tools | Options and locate the template under
mR!1DQ.\<
* the Source Creation and Management node. Right-click the template and choose M|VyV(f
* Open. You can then make changes to the template in the Source Editor. 2Zm0qJ
*/ 87=&^.~`
1}"++Z73P
package com.tot.count; a a<8,;
import tot.db.DBUtils; 0`Kj25
import java.sql.*; )z>|4@,
/** Qo>b*Ku;
* m.hkbet/R
* @author -6Z\qxKqZ
*/ $5>e
public class CountControl{ },uF4M.K
private static long lastExecuteTime=0;//上次更新时间 +20G>y=+
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 RXNn[A4xfY
/** Creates a new instance of CountThread */ fAF1"4f
public CountControl() {} S2E8Gq9
public synchronized void executeUpdate(){ GeI-\F7b
Connection conn=null; Cwr~HY
PreparedStatement ps=null; ^0Zf,40
try{ {M3qLf~z#C
conn = DBUtils.getConnection(); K~uXO
conn.setAutoCommit(false); !H#bJTXB
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); O3;u G.:1
for(int i=0;i<CountCache.list.size();i++){ ky8_UnaO
CountBean cb=(CountBean)CountCache.list.getFirst(); *F WMn.
CountCache.list.removeFirst(); ?xA:@:l/
ps.setInt(1, cb.getCountId()); iyN:%ofh
ps.executeUpdate();⑴ 'Jiw@t<o3`
//ps.addBatch();⑵ 9y6-/H
,
} ,y1PbA0m
//int [] counts = ps.executeBatch();⑶ #
q~e^A
b
conn.commit(); xg30xC[
}catch(Exception e){ Gw=B:kGk
e.printStackTrace(); ?yZ+D z\
} finally{ j 7fL7:,T
try{ $yN{-T"
if(ps!=null) { K'55O&2
ps.clearParameters(); #:jHp44J
ps.close(); V4hiGO[
ps=null; Fiv3 {.
} ,ZaRy$?
}catch(SQLException e){} {SOr#{1z*
DBUtils.closeConnection(conn); X1,I
} GC<l#3+
} Q}`0W[a
~
public long getLast(){ -#7'r<I9@
return lastExecuteTime; LuNc,n%
} ~Io7]
public void run(){ j_/>A=OD
long now = System.currentTimeMillis(); *lYVY)L
if ((now - lastExecuteTime) > executeSep) { -^K"ZP1
//System.out.print("lastExecuteTime:"+lastExecuteTime); Amp#GR1CA
//System.out.print(" now:"+now+"\n"); z-BXd
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); $:BKzHmg
lastExecuteTime=now; l~1Oef#y
executeUpdate(); &]g}u5J!=
} -O1>|y2rU
else{ au N6prGe
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); ,bXe<L)
} }bs+-K
} YA''2Ii
} Az9?Ra;U
//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 Gp1?iX?ml
>c1!p]&V
类写好了,下面是在JSP中如下调用。 I*o()
z[LNf.)}
<% 4Fa~Aog
CountBean cb=new CountBean(); "C}b%aO:
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); Hek*R?M|
CountCache.add(cb); 0[A[U_b
out.print(CountCache.list.size()+"<br>"); t=rEt>n~L
CountControl c=new CountControl(); B%"
d~5Y
c.run(); "76]u)
out.print(CountCache.list.size()+"<br>"); <W|3\p6
%>