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: Og`w ~!\
<k&Q"X:"
CountBean.java QuJ)WaJkC
O?9&6x
/* {\L /?#
* CountData.java ZLJfSnB
* 4`
gAluJ#
* Created on 2007年1月1日, 下午4:44 m. G}#/
* 1/YWDxo,
* To change this template, choose Tools | Options and locate the template under bi bjFg
* the Source Creation and Management node. Right-click the template and choose -q BrJ1*
* Open. You can then make changes to the template in the Source Editor. Vx^+Z,y&QP
*/ qqSf17sW
~%QVjzMC
package com.tot.count; afcI5w;>}
iy{*w&p
/** X99:/3MXB'
* {`vF4@
* @author >c>f6
*/ hp]T ^
public class CountBean { Z`23z(+
private String countType; 54w..8'
int countId; Lh6G"f(n
/** Creates a new instance of CountData */ dhW)<
public CountBean() {} h`OX()N
public void setCountType(String countTypes){ dw8Ce8W
this.countType=countTypes; T,,,+gPx
} gD0 FRKn
public void setCountId(int countIds){ x-km)2x=W
this.countId=countIds; ~JsTHE$F
} Ax4nx!W,
public String getCountType(){ '@h5j6:2
return countType; Bg*Oj)NM
} }^;Tt-*k
public int getCountId(){ %+U.zd$
return countId; #]'#\d#i
} 3PLv;@!#j}
} (8u.Xbdh
HgP9evz,0
CountCache.java Lmx95[#@a
O<Rm9tZ8
/* W|o LS
* CountCache.java #=@(
m.k:s
* C&b^TLe
* Created on 2007年1月1日, 下午5:01 W~J@v@..4
* ON|Bpt2Qp
* To change this template, choose Tools | Options and locate the template under A=/|f$s+
* the Source Creation and Management node. Right-click the template and choose Rdd[b?
* Open. You can then make changes to the template in the Source Editor. y-gSal
*/ :yo tpa
F7wpGtt
package com.tot.count; oO-kO!59y
import java.util.*; %l!Gt"\xm
/** f:gXXigY,
* xioL6^(Qk,
* @author "MD
*/ UUGwXq96i
public class CountCache { sXdNlR&
public static LinkedList list=new LinkedList(); -ckk2D?
/** Creates a new instance of CountCache */ ][1*.7-
public CountCache() {} SyFOf
public static void add(CountBean cb){ g<VJ4TE6R
if(cb!=null){ FWv-_
list.add(cb); )>$@cH
} <o8j+G)K#
} IPK.
} ^~k2(DLk
s_A<bW566F
CountControl.java y-qbK0=X4
>
Q+Bw"W<
/* s)ymm7?
* CountThread.java 7{
zkqug
* 5_@ u Be~
* Created on 2007年1月1日, 下午4:57 sBGYgBu!a
* Ly1V@
* To change this template, choose Tools | Options and locate the template under oqa]iBO
* the Source Creation and Management node. Right-click the template and choose E(F<shT#
* Open. You can then make changes to the template in the Source Editor. y#Je%tAe
2
*/ h0ufl.N_%
C~IsYdln
package com.tot.count; -z9-f\
import tot.db.DBUtils; PMzPe"3M
import java.sql.*; ;q&6WO
/** E Z95)pk
* Z?yMy zT
* @author Z<6XB{Nh\
*/ [m3[plwe
public class CountControl{ 1'wwwxe7
private static long lastExecuteTime=0;//上次更新时间 rcUXYJCh-
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 5(0f"zY
/** Creates a new instance of CountThread */ (he cvJ
public CountControl() {} @~v|t{G
public synchronized void executeUpdate(){ T2-n;8t
Connection conn=null; t{n|!T&
PreparedStatement ps=null; al<[iZ
try{ 6 KuB<od
conn = DBUtils.getConnection(); 4<b=;8
conn.setAutoCommit(false); SXfuPM
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); Te=[tx~x
for(int i=0;i<CountCache.list.size();i++){ e|)6zh<O:
CountBean cb=(CountBean)CountCache.list.getFirst(); >CtT_yhx
CountCache.list.removeFirst(); :=q blc
ps.setInt(1, cb.getCountId()); R#OVJ(#
ps.executeUpdate();⑴ ?-mDvW
//ps.addBatch();⑵ <smi<syx
} 41f4zisZ
//int [] counts = ps.executeBatch();⑶ `NqX{26GV+
conn.commit(); *GxOiv7"4W
}catch(Exception e){ ag Za+a
e.printStackTrace(); xxWrSl`fB
} finally{ l<fZt#T
try{ $e66j V
if(ps!=null) { n#,<-Rb-
ps.clearParameters(); ^V]DQ%v"I
ps.close(); #w\Bc\
ps=null; d4OWnPHv&}
} ck-ab0n
}catch(SQLException e){} @Sb 86Ee
DBUtils.closeConnection(conn); +X)n} jh
} ]B'Ac%Rx
} bvY'=
public long getLast(){ jb~2f2vUa
return lastExecuteTime; TX7B (JZD
} i[obQx S94
public void run(){ U40adP? a
long now = System.currentTimeMillis(); Jj=0{(X
if ((now - lastExecuteTime) > executeSep) { [C)JI; \
//System.out.print("lastExecuteTime:"+lastExecuteTime); ,MkldCV
//System.out.print(" now:"+now+"\n"); 6q^Tq {I
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); ] .Mr&@
lastExecuteTime=now; *~b3FLzq
executeUpdate(); r83chR9
} Q"UWh~
else{ ^6*LuXPv
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); $6\-8zNk
} ;4DqtR"7Y
} 6- H81y3
} |BrD:+
//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 oNV5su
V_Owi5h
类写好了,下面是在JSP中如下调用。 S}zh0`+d'Z
pAwmQS\W
<% C1
qyjlR
CountBean cb=new CountBean(); a&yIH;-
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); XEd|<+P1
CountCache.add(cb); %si5cc?
out.print(CountCache.list.size()+"<br>"); +[l52p@a
CountControl c=new CountControl(); TE+d?
c.run(); ~I^}'^Dbb
out.print(CountCache.list.size()+"<br>"); 1eG@?~G
%>