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: >5,nB<
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CountBean.java x>Hg.%/c[
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/* ryk(Am<
* CountData.java .i^aYbB$X
* 6xLLIby,
* Created on 2007年1月1日, 下午4:44 '"#W!p
* qXI>x6?*
* To change this template, choose Tools | Options and locate the template under JqX+vRY;dd
* the Source Creation and Management node. Right-click the template and choose XeGtge/}T
* Open. You can then make changes to the template in the Source Editor. =D 1%-ym
*/ Hchh2
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package com.tot.count; bf9LR1
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/** a@>P?N~LA9
* ^U[c:Rz
* @author /hx|KC&:e
*/ 3B{B6w}t&
public class CountBean { V(-=@UW
private String countType; @Yv+L)
int countId; *3,Kn}ik
/** Creates a new instance of CountData */ +:JyXFu
public CountBean() {} g\Ck!KJ/y
public void setCountType(String countTypes){ BQ We8D
this.countType=countTypes; Tc{n]TV
} ^#^\@jLm
public void setCountId(int countIds){ rD7L==Ld
this.countId=countIds; ]z^*1^u^ig
} {w,g~ew
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public String getCountType(){ D7|=ev
return countType; @qszwQav$
} U64WTS@
public int getCountId(){ hcQky/c\#b
return countId; ,5tW|=0@
} m^6& !`CD
} .Xq4QR .
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CountCache.java n/>^!S
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/* ncF|wz
* CountCache.java ^e<"`e
* Pz=x$aY
* Created on 2007年1月1日, 下午5:01 U$-;^=;
* yA74Rxl*6
* To change this template, choose Tools | Options and locate the template under 9GH11B_A
* the Source Creation and Management node. Right-click the template and choose u{Z
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* Open. You can then make changes to the template in the Source Editor.
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*/ G4VdJ(_
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package com.tot.count; \(S69@f
import java.util.*; g$z9 ( i+
/** W.B;Dy,Y
* |H.i$8_A
* @author
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*/ |oYqkP|
public class CountCache { `7f><p/q
public static LinkedList list=new LinkedList(); !9w;2Z]uum
/** Creates a new instance of CountCache */ f&z@J,_=
public CountCache() {} 6}Iu~|5
public static void add(CountBean cb){ .Mn+Bd4f
if(cb!=null){ yu<'-)T.?
list.add(cb); I04GQql
} 4| 6<nk_
} }D/O cp~o
} ]8Eci^i
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CountControl.java BA1|%:.
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/* ,KM-DCwcG
* CountThread.java C4Tn
* p "J^
* Created on 2007年1月1日, 下午4:57 T7wy{;
* 2l7Sbs7
* To change this template, choose Tools | Options and locate the template under s,tZi6Z=%E
* the Source Creation and Management node. Right-click the template and choose H[cHF
* Open. You can then make changes to the template in the Source Editor. D8w:c6b
*/ u$3wdZ2&m
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package com.tot.count; 6:(R/9!P
import tot.db.DBUtils; \[nvdvJv
import java.sql.*; NXJyRAJ*%
/** G>3]A5
* -G!W6$Y
* @author @[:JQ'R=
*/ u{H'evv0O
public class CountControl{ =p1aF/1$I
private static long lastExecuteTime=0;//上次更新时间 zF%'~S0{
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 Ql%0%naq1
/** Creates a new instance of CountThread */ h{$mL#J
public CountControl() {} Vy+%sG
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public synchronized void executeUpdate(){ 4 ^=qc99
Connection conn=null; i?*_-NAm
PreparedStatement ps=null; yq?7!X
try{
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conn = DBUtils.getConnection(); Hy?+p{{G
conn.setAutoCommit(false); tt|v opz
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); $. ;j4%%
for(int i=0;i<CountCache.list.size();i++){ c`hj^t
CountBean cb=(CountBean)CountCache.list.getFirst(); t
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CountCache.list.removeFirst(); &8l4A=l$
ps.setInt(1, cb.getCountId()); Mp8FYPjZ
ps.executeUpdate();⑴ #6jdv|fu
//ps.addBatch();⑵ r_5k$u(
} 6I)1[tU
//int [] counts = ps.executeBatch();⑶ dzK]F/L]
conn.commit(); j:JM v
}catch(Exception e){ vlHE\%{
e.printStackTrace(); x6d0yJ <
} finally{ h`_@eax
try{ &TpzJcd"
if(ps!=null) { 34@f(^d+^
ps.clearParameters(); fP6]zy^*
ps.close(); &oA p[]
ps=null; __FhuP P
} SM<kR1bo
}catch(SQLException e){} f9Vxtd
DBUtils.closeConnection(conn); af:wg]g
} U%Igj:%?;`
} k:+Bex$g
public long getLast(){ #ny&bJj
return lastExecuteTime; np>RxiB^
} 5i 6*$#OM_
public void run(){ K*ZH<@o4
long now = System.currentTimeMillis(); LX
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if ((now - lastExecuteTime) > executeSep) { v(HCnC
//System.out.print("lastExecuteTime:"+lastExecuteTime); @iW^OVpp<8
//System.out.print(" now:"+now+"\n"); 'G.^g}N1
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); NXwlRMbo
lastExecuteTime=now; ]h
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executeUpdate(); b),_rr
} F(-1m A&-
else{ S`!MoIMsD
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); 6Y#V;/gK!5
} 4z~%gt74O]
} &HPzm6.3
} ";)SA,Z
//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 D^E+#a 1
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类写好了,下面是在JSP中如下调用。 7_AR()CM
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<% 80/6-_g(
CountBean cb=new CountBean();
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cb.setCountId(Integer.parseInt(request.getParameter("cid"))); m &U
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CountCache.add(cb); SqiLp!Y`
out.print(CountCache.list.size()+"<br>"); /1Xji0LK
CountControl c=new CountControl(); L@ b8,
c.run(); 91Cg
out.print(CountCache.list.size()+"<br>"); qU'O4TWZ
%>