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: ,wy;7T>ODd
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CountBean.java w{]B)>! 1W
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/* "W_E!FP]r
* CountData.java J?tnS6V
* 6="o&!
* Created on 2007年1月1日, 下午4:44 \x5>H:\Y
* ZT`"
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* To change this template, choose Tools | Options and locate the template under MJa`4[/
* the Source Creation and Management node. Right-click the template and choose "#iO{uMWb
* Open. You can then make changes to the template in the Source Editor. TJB4N$-}A
*/ eKU4"XTk
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package com.tot.count; uzLm TmM+
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/** $U(D*0+o/
* mxe\+j#
* @author >
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*/ !>&G+R+k
public class CountBean { J%fJF//U
private String countType; a
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int countId; g;:3I\ L
/** Creates a new instance of CountData */ G/w@2lYx
public CountBean() {} OT"j V
public void setCountType(String countTypes){ ETR7%0$r
this.countType=countTypes; ?zVcP=p@
} dkSd
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public void setCountId(int countIds){ )]Sf|@K]
this.countId=countIds; PTTUI
} ]{I>HA5[
public String getCountType(){ y{XNB}E
return countType; *$/Go8t4u
} ucbtPTFYvr
public int getCountId(){ 8
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return countId; *Tmqs@L
} gLx?0eBBA
} T>&dPVmG,
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CountCache.java !A14\
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/* VRHS 4
* CountCache.java x_l8&RIB*
* nppSrj?
* Created on 2007年1月1日, 下午5:01 R/6
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* A}3E)Qo=G
* To change this template, choose Tools | Options and locate the template under r\y\]AmF
* the Source Creation and Management node. Right-click the template and choose ZY;g)`E1
* Open. You can then make changes to the template in the Source Editor. ")NQwT}
*/ KCqz]
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package com.tot.count; :JXcs39
import java.util.*; -vt6n1A&b
/** '|M} 3sL
* :73T9/
* @author R80|q#h,]
*/ F(,SnSam
public class CountCache { xx?0Ftuq
public static LinkedList list=new LinkedList(); <YWu/\{KT
/** Creates a new instance of CountCache */ ol_&epG;ST
public CountCache() {} 3;!a'[W&p
public static void add(CountBean cb){ /N@NT/.M<
if(cb!=null){ mmMiA@0
list.add(cb); =sS=
} MJKPpQ(,
} .&K?@T4l
} XD[9wd5w8
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CountControl.java 9(bbV5}
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/* &((04<@e
* CountThread.java +^$;oG
* HS1{4/
* Created on 2007年1月1日, 下午4:57 kC'm |Y@T
* %,d+jBM
* To change this template, choose Tools | Options and locate the template under U:$`M,762Z
* the Source Creation and Management node. Right-click the template and choose ubsx NCqD
* Open. You can then make changes to the template in the Source Editor. =
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*/ u4[JDB7tH
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package com.tot.count; paxZlA
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import tot.db.DBUtils; Zh?n;n}
import java.sql.*; M@0S*[O{"
/** )EN,Ry
* 26j-1c!NGd
* @author `EiL~*
*/ LBcqFvj{&
public class CountControl{ 3V]psZS
private static long lastExecuteTime=0;//上次更新时间 ;[|+tO_
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 {|e7^_ ke
/** Creates a new instance of CountThread */ E/E|*6R
public CountControl() {} &(20*Vn,O
public synchronized void executeUpdate(){ mUiJ@
Connection conn=null; WkoYkkuzj
PreparedStatement ps=null; 7re4mrC
try{ FwQGxGZ
conn = DBUtils.getConnection(); X,K`]hb*0_
conn.setAutoCommit(false); pf3-
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); ww\2
for(int i=0;i<CountCache.list.size();i++){ c>C!vAg
CountBean cb=(CountBean)CountCache.list.getFirst();
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CountCache.list.removeFirst(); vLCm,Bb2L
ps.setInt(1, cb.getCountId()); 73!])!SVI
ps.executeUpdate();⑴ <*p
//ps.addBatch();⑵ H#bu3*'
} F+V[`w*k
//int [] counts = ps.executeBatch();⑶ BkDq9>
conn.commit(); CTc#*LJx>j
}catch(Exception e){ z}p*";)A
e.printStackTrace(); }5?|iUH|
} finally{ b+71`aD0
try{ ck8Qs08
if(ps!=null) { TG.\C8;vFh
ps.clearParameters(); WVL\|y728s
ps.close(); 57$/Dn
ps=null; ;ZZmX]kz,M
} QX9['B<
}catch(SQLException e){} 6%T_;"hb
DBUtils.closeConnection(conn); -"xC\R
} -}Rh+n`
} 'gk^NAG2^E
public long getLast(){ H]Gj$P=k
return lastExecuteTime; hud'@O"R+
} ,9.NMFn
public void run(){ 0fR?zT?
long now = System.currentTimeMillis(); D\sh
+}"
if ((now - lastExecuteTime) > executeSep) { BagV\\#v4
//System.out.print("lastExecuteTime:"+lastExecuteTime); mpl^LF[
//System.out.print(" now:"+now+"\n"); `P;uPQDzZ3
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); lq27^K
lastExecuteTime=now; W1Om$S1
executeUpdate(); @h7
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} ]T>YYz
else{ .O9Pn,:
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); JWQ.Efe
} A2B]E,JMp
} +#g4Crb
} x
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//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 pz/vvH5
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类写好了,下面是在JSP中如下调用。 ;B"S*wYMN
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<% {^K&9sz
CountBean cb=new CountBean(); e73zpF
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); HOVzpj
CountCache.add(cb); 0&2&F=fOa<
out.print(CountCache.list.size()+"<br>"); $H7T|`WI.,
CountControl c=new CountControl(); a3BlydSlf
c.run(); L4Si0 K
out.print(CountCache.list.size()+"<br>"); |C\XU5}
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