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: 4!,x3H'
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CountBean.java
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/* eaCv8zdX
* CountData.java jQ@z!GirT
* 7RM$%'n\
* Created on 2007年1月1日, 下午4:44 8-3]Bm!
* d4t%/ Uh
* To change this template, choose Tools | Options and locate the template under 9'faH
* the Source Creation and Management node. Right-click the template and choose w,> ceu/
* Open. You can then make changes to the template in the Source Editor. thIuK V{CO
*/ BSYJ2
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package com.tot.count; w2_$>z
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/** Y^Y|\0
* |RS9N_eRt
* @author Pky/fF7e
*/ RTHD2
public class CountBean { A^nB!veh
private String countType; SB0Cq
int countId; S\b[Bq
/** Creates a new instance of CountData */ CtJ*:wF
public CountBean() {} F=!p7msRB
public void setCountType(String countTypes){ rrbD0UzFA
this.countType=countTypes; |N/Grk4
} GM=r{F
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public void setCountId(int countIds){ | s%--W
this.countId=countIds; X Uc(7>k
} 0Am&:kX't
public String getCountType(){ uP2e/a
return countType; dU<\FW_
} jcD_<WSe
public int getCountId(){ wO9|_.Z{
return countId; ej,j1iB
} FOVghq@
} }vzP\
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CountCache.java ~o_0RB
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/* ,|6O}E&
* CountCache.java FFX-kS
* k%Dpy2uH
* Created on 2007年1月1日, 下午5:01 nb
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* ea[vzD]
* To change this template, choose Tools | Options and locate the template under -d5b,leC^
* the Source Creation and Management node. Right-click the template and choose @a2n{
* Open. You can then make changes to the template in the Source Editor. djJD'JL
*/ 4Bg"b/kF
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package com.tot.count; Tq{+9+
import java.util.*; (37dD!
/** t 66Cx
* }#):ZPTs
* @author YbAa@Sq@
*/ ;]c@%LX
public class CountCache { |2t
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public static LinkedList list=new LinkedList(); nMm4fns
/** Creates a new instance of CountCache */ 1oU/gm$7\q
public CountCache() {} 0%J0.USkM7
public static void add(CountBean cb){ 9/2VU<
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if(cb!=null){ m#6RJbEz
list.add(cb); *g7BR`Bt]z
} Y\s ge
} 4P(muOS
} X.}i9a
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CountControl.java JC6?*R
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/* =D-u".{
* CountThread.java =T"R_3[NC
* cG!\P: re
* Created on 2007年1月1日, 下午4:57 D2}N6i
* Nini8@d
* To change this template, choose Tools | Options and locate the template under rSu+zS7`X
* the Source Creation and Management node. Right-click the template and choose M;2@<,rM
* Open. You can then make changes to the template in the Source Editor. |)~t^
*/ eka<mq|W
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package com.tot.count; FK;3atrz
import tot.db.DBUtils; 5<64 C}fE3
import java.sql.*; w{F{7X$^
/** |ppG*ee
* yuP1*QJ%
* @author 1N\/61+aA
*/ g{ ()
public class CountControl{ b5i ehoA
private static long lastExecuteTime=0;//上次更新时间 aF8'^xF
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 xhcFZTj/(
/** Creates a new instance of CountThread */ _43'W{%
public CountControl() {} ^mwS6WH6
public synchronized void executeUpdate(){ pW&K=,7|
Connection conn=null; Q Ev7k
PreparedStatement ps=null; $'*q]]
try{ B^;"<2b*
conn = DBUtils.getConnection(); + /+> :
conn.setAutoCommit(false); deLLqdZa
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); w'uB&z4'
for(int i=0;i<CountCache.list.size();i++){ 6W\G i>
CountBean cb=(CountBean)CountCache.list.getFirst(); q4MR9ig1E_
CountCache.list.removeFirst(); X,xCR]+5S
ps.setInt(1, cb.getCountId()); ^cDHC^Wm
ps.executeUpdate();⑴ j_3`J8WwF
//ps.addBatch();⑵ Rf4}((y7Y\
} gN@|lHbU
//int [] counts = ps.executeBatch();⑶ k~%j"%OB
conn.commit(); Am
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}catch(Exception e){ X+2uM+
e.printStackTrace(); VW`SqUl
} finally{ WuuF&0?8C
try{ X 0vcBHh
if(ps!=null) { ;yu#Bs
ps.clearParameters(); =;Q:z^S
ps.close(); 3xIelTf*
ps=null; h0.2^vM)R
} n }kn|To~
}catch(SQLException e){} q-hR EO
DBUtils.closeConnection(conn); \s?8}k
} U9"(jl/o
} -I?8\
public long getLast(){ I+{2DY/}
return lastExecuteTime; a%nf
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} q0C%">>1#
public void run(){ vSnGPLl
long now = System.currentTimeMillis(); (S~kNbIa
if ((now - lastExecuteTime) > executeSep) { (b;Kl1Ql]
//System.out.print("lastExecuteTime:"+lastExecuteTime); zC,c9b
//System.out.print(" now:"+now+"\n"); i 558&:
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); pC~M5(F_
lastExecuteTime=now; 5>6:#.f%!e
executeUpdate(); 1*GL;W~ix*
} }el7@Gv
else{ Xj9\:M-
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); bWgRGJqt
} X5pb9zRq
} \
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} 6H1;Hl
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//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 F| jl=i
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类写好了,下面是在JSP中如下调用。 s(T0lul
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<% XL[Dmu&
CountBean cb=new CountBean(); %Q]3`kxp
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); ZEK,Z['
CountCache.add(cb); OO2uE ;( 3
out.print(CountCache.list.size()+"<br>"); S]&:R)#@
CountControl c=new CountControl(); n$ rgJ
c.run(); Xub*i^(]
out.print(CountCache.list.size()+"<br>"); ,j6R/sg
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