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: L<H zPg
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CountBean.java Zog&:]P'F
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/* tcD DX'S
* CountData.java /]>8V'e\
* Je &O
* Created on 2007年1月1日, 下午4:44 dW#T1mB
* O;8 3A
* To change this template, choose Tools | Options and locate the template under W:S?_JM
* the Source Creation and Management node. Right-click the template and choose ZgI ?#e
* Open. You can then make changes to the template in the Source Editor. 1G`zwfmh~
*/ \\9I:-j:p
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package com.tot.count; }BN!Xa
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/** 7 <<`9,
* -J]j=
* @author bx._,G
*/ .g?Ppma
public class CountBean { 5[0W+W
private String countType; 5KgAY;|
int countId; .8]buM5_G
/** Creates a new instance of CountData */ YMr2Dv\y
public CountBean() {} %}[/lIxaE
public void setCountType(String countTypes){ o>75s#=
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this.countType=countTypes; _X)`S"EsJ
} 3{H&{@Q
public void setCountId(int countIds){ a%*W(
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this.countId=countIds; -jWXE
} #I}w$j
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public String getCountType(){ Dj9ecV`
return countType; 34:Y_*
} Zt
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public int getCountId(){ #7Jvk_r9Y
return countId; WGA"e
} 8;y\Ln?B
} ]=G dAW
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CountCache.java uFnq 3m^u
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/* "?S>}G\
* CountCache.java @S)p{T5G
* <tgfbY^nL
* Created on 2007年1月1日, 下午5:01 1k!$#1d<
* XM~eocn
* To change this template, choose Tools | Options and locate the template under \2[sUY<W
* the Source Creation and Management node. Right-click the template and choose 'k9Qd:a}
* Open. You can then make changes to the template in the Source Editor. ks7id[~&iY
*/ b&P2VqYgl
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package com.tot.count; @r]1;KG
import java.util.*; f"Kl?IN8
/** =VGRM#+D
* <(_${zR
* @author nVoP:FHH
*/ c F}9ldc
public class CountCache { n0b{Jg *
public static LinkedList list=new LinkedList(); pykRi#[UrX
/** Creates a new instance of CountCache */ 9M7Wlx2
public CountCache() {} ESi-'R&
public static void add(CountBean cb){ mhMRY9 ahB
if(cb!=null){ 4IXa[xAm
list.add(cb); NT<}-^
} i+~H~k}"X
} @T)>akEOt
} YzYj/,?r
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CountControl.java }u.1$Y
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/* %:Y'+!bX
* CountThread.java
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* VL2ACv(
* Created on 2007年1月1日, 下午4:57 UQ~gjnb[c
* 3$PGLM
* To change this template, choose Tools | Options and locate the template under pXf5/u8&
* the Source Creation and Management node. Right-click the template and choose H;Gd
* Open. You can then make changes to the template in the Source Editor. bix}#M
*/ SOeRQb'
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package com.tot.count; (5>IF,}!L
import tot.db.DBUtils; 2YpJ4.
import java.sql.*; e89IT*
/** \&4)['4,
* G`NGt_C
* @author #.|MV}6rQ
*/ 7-c3^5gn{
public class CountControl{ X -_0wR
private static long lastExecuteTime=0;//上次更新时间 yT h60U
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 K!;>/3Y2-
/** Creates a new instance of CountThread */ Kbcr-89Gv~
public CountControl() {} O>>%lr|
public synchronized void executeUpdate(){ 2x:aMWh
Connection conn=null; 9On(b|mT
PreparedStatement ps=null; 4H hQzVM{
try{ I=|}%WO#
conn = DBUtils.getConnection(); H#B97IGT
conn.setAutoCommit(false); P|;=dX#-
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); (z^987G
for(int i=0;i<CountCache.list.size();i++){ J(k C
CountBean cb=(CountBean)CountCache.list.getFirst(); ^\FOMGai
CountCache.list.removeFirst(); 3/*<i
ps.setInt(1, cb.getCountId()); $-M'
ps.executeUpdate();⑴ 5<Y-?23
//ps.addBatch();⑵ E7j9A`
} !\|L(Paf
//int [] counts = ps.executeBatch();⑶ v}&J*}_XZ
conn.commit(); ]t;bCD6*
}catch(Exception e){ Te@=8-u-
e.printStackTrace(); rNeSg=j
} finally{ zwdi$rM5
try{ Q9sxI}D )R
if(ps!=null) { \ O+Hmi^
ps.clearParameters(); ux1SQ8C *
ps.close(); B2)SNhF2Y
ps=null; 2IFEl-IB[
} =R0#WMf$@
}catch(SQLException e){} %$zX a%A
DBUtils.closeConnection(conn); dwmZ_m.
} |"k+j_/+
} 8&++S> <
public long getLast(){ 5+Hw @CY3
return lastExecuteTime; c8M'/{4rH
} TbR!u:J
public void run(){
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long now = System.currentTimeMillis(); fC!+"g55
if ((now - lastExecuteTime) > executeSep) { (zhi/>suG
//System.out.print("lastExecuteTime:"+lastExecuteTime); -+&sPrQ
//System.out.print(" now:"+now+"\n"); Xv?'*2J
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); |Whkq/Zg
lastExecuteTime=now; !T1)tGrH
executeUpdate(); uOQl;}Lk5
} A9ru]|?
else{ %<;PEQQ|C
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); _2nNCu (
} mY!&*nYn|
} ,B$m8wlI|
} 8?&!@3n
//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 h}f l:J1C
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类写好了,下面是在JSP中如下调用。 PVX23y;
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<% Gcd'- 1
CountBean cb=new CountBean(); 2JLXDkZ
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); uDsof?z
CountCache.add(cb); Ib0@,y S[
out.print(CountCache.list.size()+"<br>"); Bey|f/
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CountControl c=new CountControl(); 1|3{.Ed
c.run(); .eG_>2'1
out.print(CountCache.list.size()+"<br>"); KU)~p"0[6]
%>