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: y/\ZAtnLo
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CountBean.java +wA p,Xr
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/* }5hZo%w[n
* CountData.java >#?iO]).
* XHNkQe
* Created on 2007年1月1日, 下午4:44 _.-#E$6s#q
* k.Gl4
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* To change this template, choose Tools | Options and locate the template under -R8/`M8GbD
* the Source Creation and Management node. Right-click the template and choose 6VFirLd
* Open. You can then make changes to the template in the Source Editor. NfqJ=9
*/ 23k)X"5
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package com.tot.count; C (U
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/** :mn(0
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* C$_G'XI
* @author F {/>u(@3
*/ R.O
public class CountBean { Cy6%S).c
private String countType; 0}D-KvjyP
int countId; X&.:H~xS+
/** Creates a new instance of CountData */ >~^`5a`$uI
public CountBean() {} Qxky^:B
public void setCountType(String countTypes){ 8XlU%a6x
this.countType=countTypes; y,V6h*x2
} qL,ka
public void setCountId(int countIds){ ETxp#PZ
this.countId=countIds; #)FDl70S8
} 6UO$z- e
public String getCountType(){ Enu!u~1]F
return countType; !*5_pGe
} W oWBs)E
public int getCountId(){ C_-%*]*,j
return countId; _TrZ'iL}T
} ovB=Zm
} 8-A:k E
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CountCache.java B#QL M^
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/* ~Po\ En
* CountCache.java & \JLTw
* K[*h+YO
* Created on 2007年1月1日, 下午5:01 Shs')Zsbv
* 40R"^*
* To change this template, choose Tools | Options and locate the template under z}iSq$
* the Source Creation and Management node. Right-click the template and choose gU~
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* Open. You can then make changes to the template in the Source Editor. 8>ESD}(
*/ #t){ 4J
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package com.tot.count; u2Y N[|V
import java.util.*; v: giZxR
/** pa>p%
* .#"1bRWpZ
* @author s%5Uj}
*/ WUzSlZq
public class CountCache { (Z5qf
public static LinkedList list=new LinkedList(); 93 [rL+l.Y
/** Creates a new instance of CountCache */ $|rCrak;
public CountCache() {} K*TnUQ
public static void add(CountBean cb){ z'?SRK5+
if(cb!=null){ 6BUBk>A`
list.add(cb); I+*osk
} *@CVYJ'<
} R_t~UTfI;
} H3!,d`D.N
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CountControl.java D% oueW
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/* G}182"#4
* CountThread.java GVeL~Q
* kZJt~}
* Created on 2007年1月1日, 下午4:57 7F,07\c
* 4 U3C~J
* To change this template, choose Tools | Options and locate the template under , - QR
* the Source Creation and Management node. Right-click the template and choose :8](&B68gE
* Open. You can then make changes to the template in the Source Editor. c]GQU
*/ $$k7_rs
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package com.tot.count; c'"#q)
import tot.db.DBUtils; k}- "0>
import java.sql.*; SCgyp(
/** YI L'YNH
* C/SapX
* @author ue,#,3{m
*/ W/#KX}4
public class CountControl{ n;e."^5
private static long lastExecuteTime=0;//上次更新时间 y2oB]^z&n
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 {CW1t5$*
/** Creates a new instance of CountThread */ Mr$# e
public CountControl() {} M' &J_g
public synchronized void executeUpdate(){ 7xX;MB&
Connection conn=null; |E46vup
PreparedStatement ps=null; b{Z^)u2X
try{ lo\: ]/&6
conn = DBUtils.getConnection(); 6"BtfQ")
conn.setAutoCommit(false); I8%d;G~
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); %M|Z}2qv
for(int i=0;i<CountCache.list.size();i++){ @WhZx*1
CountBean cb=(CountBean)CountCache.list.getFirst(); SNQz8(O
CountCache.list.removeFirst(); \;nD)<)J
ps.setInt(1, cb.getCountId()); *54>iO-
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ps.executeUpdate();⑴ CnxK+1n l
//ps.addBatch();⑵ b=6MFPbg
} vpZu.#5c
//int [] counts = ps.executeBatch();⑶ L~@ma(TV{K
conn.commit(); 43vGgGW
}catch(Exception e){ >t1_5
e.printStackTrace(); ^VSt9&
} finally{ Xz;et>UD*B
try{ xI=}z
if(ps!=null) { =gxgS<bde
ps.clearParameters(); <_##YSGh,
ps.close(); b:N^Fe
ps=null; ti$oZ4PpF
} XNc"kp? z
}catch(SQLException e){} (|yRo
DBUtils.closeConnection(conn); >yV)d/
} += |hMQ;
} aukk|/3Ih
public long getLast(){ tYI]LL
return lastExecuteTime; :FX'[7;p
} .Q=2WCv0
public void run(){ #6Efev
long now = System.currentTimeMillis(); .){e7U6b{
if ((now - lastExecuteTime) > executeSep) { P!`Q_h6a
//System.out.print("lastExecuteTime:"+lastExecuteTime); Y9IJ
//System.out.print(" now:"+now+"\n"); QU-7Ch#8
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); *G%1_
lastExecuteTime=now; !Z<mrr;T@
executeUpdate(); U^E
} /3CHE8nSh
else{ blKDQ~T2
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); c,#~L7
} ^4xlZouCb
} p56KS5duI.
} e.)yV'%L
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 fZka%[B
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类写好了,下面是在JSP中如下调用。 b
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<% #}[Sj-Vp
CountBean cb=new CountBean(); 8Pr&F
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); TIK/ %T
CountCache.add(cb); N>&{Wl'y \
out.print(CountCache.list.size()+"<br>"); G"T;l"TAt8
CountControl c=new CountControl(); F]K$u<U
c.run(); W%Y.SP$Y
out.print(CountCache.list.size()+"<br>"); zh#OD{
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