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: @Ys(j$U't
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CountBean.java f]J?-ks
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/* deda=%w0
* CountData.java z=?ainnKx
* Nr|.]=K)5n
* Created on 2007年1月1日, 下午4:44 -XPGl
* o5BOe1_Pw
* To change this template, choose Tools | Options and locate the template under ~.VWrHC
* the Source Creation and Management node. Right-click the template and choose V tZ
* Open. You can then make changes to the template in the Source Editor. jO3Q@N0_
*/ j8hb
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package com.tot.count; :*/<eT_
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/** p!hewtb5
* 85w
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* @author |uj1T=ZY
*/ P2 !~}{-
public class CountBean { F2z^7n.S
private String countType; Mff_j0D
int countId; WxWgY}`
/** Creates a new instance of CountData */ A}t.`FLP,j
public CountBean() {} FK
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public void setCountType(String countTypes){ wZE[we^Q"
this.countType=countTypes; RLw=y{%p
} D<5gdIw
public void setCountId(int countIds){ \X
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this.countId=countIds; '/z.\ S
} sN5x\9U
public String getCountType(){ H1s{JJAM>i
return countType; )WwysGkqol
} o7DDL{iR/
public int getCountId(){ e4khReF;
return countId; rZKv:x}{6
}
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} O|4~$7
3|/ ;`KfQ
CountCache.java jdXkU
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/* X'7 T" 5!
* CountCache.java #y-OkGS
^
* bsP:tFw>
* Created on 2007年1月1日, 下午5:01 rnmWw#
* H+zQz8zMC
* To change this template, choose Tools | Options and locate the template under O JvEq@
* the Source Creation and Management node. Right-click the template and choose y?_tSnDK
* Open. You can then make changes to the template in the Source Editor. 9oKRu6]D-
*/ *>$'aQ
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package com.tot.count; h&h]z[r R
import java.util.*; iMk`t:!;#"
/** k8Qv>z
* va~:oA
* @author qW?^_
*/ s^L\hr
public class CountCache { Sn7.KYS
public static LinkedList list=new LinkedList(); R?Iv<(I
/** Creates a new instance of CountCache */ D 67H56[
public CountCache() {} &fiDmUxj
public static void add(CountBean cb){ 4y>G6TD^
if(cb!=null){ '9$xOrv
list.add(cb); wUh'1D<(r
} |Ro\2uSr
} ;6fkG/T
} SY>N-fW\H:
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CountControl.java XO"!)q F
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/* G5TdAW
* CountThread.java Nf<([8v;t
* q^(A6W
* Created on 2007年1月1日, 下午4:57 I BES$[
* ?#J~X\5
* To change this template, choose Tools | Options and locate the template under IB(IiF5
* the Source Creation and Management node. Right-click the template and choose AGLzA+6M
* Open. You can then make changes to the template in the Source Editor. NawnC!~ $
*/ ^R>&^"oI
%#/7Tl:
package com.tot.count; nzhQ\'TC
import tot.db.DBUtils; s8.oS);`
import java.sql.*; YHvmo@
/** @ mtv2P`
* B quyPG"
* @author KhXW5hS1
*/ X+P3a/T
public class CountControl{ D2>=^WP6+
private static long lastExecuteTime=0;//上次更新时间 "84.qgYaG
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 OwSr`2'9
/** Creates a new instance of CountThread */ top3o{4
public CountControl() {} 8Ln:y'K
public synchronized void executeUpdate(){ MbYa6jrF
Connection conn=null; {P1W{|
PreparedStatement ps=null; 5OpK~f5
try{ &EA4`p
conn = DBUtils.getConnection(); )oAK)e
conn.setAutoCommit(false); pf] sL/g
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); FjkE^o>
for(int i=0;i<CountCache.list.size();i++){ >"zSW?
CountBean cb=(CountBean)CountCache.list.getFirst(); s49AF
CountCache.list.removeFirst(); w
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ps.setInt(1, cb.getCountId()); pBK[j([
ps.executeUpdate();⑴ > {fX;l
//ps.addBatch();⑵ mR8&9]g&
} ,h8)5Mj/J
//int [] counts = ps.executeBatch();⑶ o#%2N+w
conn.commit(); VNXB7#ry
}catch(Exception e){ ~[k2(
e.printStackTrace(); CIO&VK
} finally{ `lcpUWn
try{ NBUM* Z
if(ps!=null) { @B+
ps.clearParameters(); PuUqWW'^
ps.close(); cN&b$8O=%
ps=null; y$4,r4cmR|
} J]fjg%C2m
}catch(SQLException e){} O2 3f\pm&
DBUtils.closeConnection(conn); bG2!5m4L
} 7v%~^l7:x
} ~q-|cl<
public long getLast(){ W9a H]9b
return lastExecuteTime; l}:9)nXA{
} ~[ve?51
public void run(){ X1tAV>k5'L
long now = System.currentTimeMillis(); U{i9h6b"18
if ((now - lastExecuteTime) > executeSep) { {U-VInu
//System.out.print("lastExecuteTime:"+lastExecuteTime); c @2s!bs
//System.out.print(" now:"+now+"\n"); l$zo3[
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); LR-op?W
lastExecuteTime=now; 33"{"2==`
executeUpdate(); ;rd!kFd#bq
} x<9|t(
else{ -!wm]kx
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//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); {#>@h7
} lt}|Y9h
} V,
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} Z{u*vUC&
//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 @kI^6(.
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类写好了,下面是在JSP中如下调用。 -kQ{~">w
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<% h2h$UZIv
CountBean cb=new CountBean(); B-r9\fi,
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); r95$B6
CountCache.add(cb); 4v E,nx=
out.print(CountCache.list.size()+"<br>"); D/@:wY
CountControl c=new CountControl(); E
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c.run(); X Uh)z
out.print(CountCache.list.size()+"<br>"); O6k[1C
%>