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: a?cJl
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CountBean.java #(8|9
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/* [K!9xM6
* CountData.java IK~&`n](>
* TkbaoD
* Created on 2007年1月1日, 下午4:44 EY}:aur
* }pc9uvmIJ
* To change this template, choose Tools | Options and locate the template under @ZKf3,J0
* the Source Creation and Management node. Right-click the template and choose 6 SSDc/
* Open. You can then make changes to the template in the Source Editor. Jd2.j?P=
*/ Y.tx$%
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package com.tot.count; cTqkM@S
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/** 2z.ot'
* H=t"qEp
* @author YIU3}sJ!
*/ DL]tg[w{
public class CountBean { '`];=QY9pg
private String countType; @[$_cGR7
int countId; sE1cvAw9l
/** Creates a new instance of CountData */ +/:tap|V
public CountBean() {} q2GW3t
public void setCountType(String countTypes){ 6Rd4waj_,U
this.countType=countTypes; NE995;
} 5~Y`ikwxL
public void setCountId(int countIds){ IRdt:B|@
this.countId=countIds; E+td~&x
} IG-\&
public String getCountType(){ s6H'}[E<
return countType; ZedFhm
} tAX*CMW
public int getCountId(){ 8fR(y~_gF
return countId; w =^.ICyb@
} bOY;IB
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} PnsBDf%v
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CountCache.java t [QD#;
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/* 3v* ~CQy9
* CountCache.java >1y6DC
* EM,C
* Created on 2007年1月1日, 下午5:01 BD g]M/{
* 1MelHW
* To change this template, choose Tools | Options and locate the template under _z5/&tm_H
* the Source Creation and Management node. Right-click the template and choose Io6/Fv>!
* Open. You can then make changes to the template in the Source Editor. GW2\YU^{
*/ \l+v,ELX=
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package com.tot.count; x)5}:b1B=
import java.util.*; J3$>~?^1
/** [^H2'&]
* Obdn#Wm=
* @author 3f;=#|l
*/ LZ*8YNp1'
public class CountCache { _vQ52H,
public static LinkedList list=new LinkedList(); |diI(2w
/** Creates a new instance of CountCache */ _ _O f0<
public CountCache() {} ~^t@TMk$
public static void add(CountBean cb){ OG\i?N
if(cb!=null){ $-4](br|
list.add(cb); .6?"<zdPU
} &$"#hGg
} p6M9uu
} X-pbSq~5
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CountControl.java {I#_0Q,i
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/* 0RR |!zEu
* CountThread.java 9u=A:n\
* $ {yct
* Created on 2007年1月1日, 下午4:57 fv+]iK<{
* bQ<qdGa
* To change this template, choose Tools | Options and locate the template under 3bEcKA_z(
* the Source Creation and Management node. Right-click the template and choose FaHOutP
* Open. You can then make changes to the template in the Source Editor. XqH@3Ehk
*/ 5#Er& 6s
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package com.tot.count; ;$p !dI\-Q
import tot.db.DBUtils; !pU$'1D
import java.sql.*; rxCzPF
/** )>a~ %~:
* m$0W^u
* @author LIg1U
*/ Q3@ zUjq_Q
public class CountControl{ yi7.9/;a
private static long lastExecuteTime=0;//上次更新时间 R >x d*A
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 w[~G^x&
/** Creates a new instance of CountThread */ i'Y8-})
public CountControl() {} n,I3\l9
public synchronized void executeUpdate(){ '/Aq2
Connection conn=null; hgU;7R,?ir
PreparedStatement ps=null;
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try{ c3]t"TA,
conn = DBUtils.getConnection(); qs4jUm
conn.setAutoCommit(false); }YwaN'3p!
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); HoI6(t
for(int i=0;i<CountCache.list.size();i++){ E@VQxB7+
CountBean cb=(CountBean)CountCache.list.getFirst(); tE*BZXBlm
CountCache.list.removeFirst(); 87
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ps.setInt(1, cb.getCountId()); Bdo{zv&A
ps.executeUpdate();⑴ ^[<BMk
//ps.addBatch();⑵ Ek+R
} "*vrrY
//int [] counts = ps.executeBatch();⑶ zs$r>rlO
conn.commit(); 4o>y9
}catch(Exception e){ EQ%o oAb8
e.printStackTrace(); qqDg2,Yb
} finally{ 2D 4,#X
try{ Gxr\a2Z&r%
if(ps!=null) { qS?o22
ps.clearParameters(); =<]`'15"V
ps.close(); HxI6_ >n^I
ps=null; H'AN osv
} 2 6#p,P
}catch(SQLException e){} Ak[X`e T
DBUtils.closeConnection(conn); Dka,v
} v9(5HY
} \Qml~?$@lH
public long getLast(){ *-0s
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return lastExecuteTime; H cmW
} e5_Hmuk|
public void run(){ U[C>Aoze
long now = System.currentTimeMillis(); n%E,[JT
if ((now - lastExecuteTime) > executeSep) { zx@!8Z
//System.out.print("lastExecuteTime:"+lastExecuteTime); [@@{z9c
//System.out.print(" now:"+now+"\n"); aH}/+Hu-
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); a4:GGzt
lastExecuteTime=now; o30C\
executeUpdate(); u(vZOf]jL
} vQ rxx
else{ [f+wP|NKL
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); 7FH(C`uKi
} mTe3%( LD
} (%_X{R'
} pRQ7rT',v
//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 !*]i3 ,{7v
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类写好了,下面是在JSP中如下调用。 BX_yC=S
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<% a1pp=3Pd?~
CountBean cb=new CountBean(); $J1`.Q>)4
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); h,/Aq
CountCache.add(cb); 8063LWV
out.print(CountCache.list.size()+"<br>"); 're:_;lG
CountControl c=new CountControl(); (xgw';g
c.run(); =$OGHc
out.print(CountCache.list.size()+"<br>"); BX/3{5Y>{
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