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: s5Wb iOF
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CountBean.java Y7I\<JG<
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/* tTubW=H
* CountData.java 2|WM?V&
* fU$_5v4
* Created on 2007年1月1日, 下午4:44 59"tHb6 E
* >LH}A6dUC
* To change this template, choose Tools | Options and locate the template under !;d>}iE
* the Source Creation and Management node. Right-click the template and choose gh
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* Open. You can then make changes to the template in the Source Editor. JR&yaOws
*/ 5v`lCu]
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package com.tot.count; D:z_FNN
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/** hsYE&Np_Q
* .=d40m
* @author PyK!Cyq
*/ !#*#ji xo
public class CountBean { BpX` 49
private String countType; /iAhGY
int countId; $e,r>tgD
/** Creates a new instance of CountData */ gSj0+|
public CountBean() {} B%kC>J
public void setCountType(String countTypes){ 0*oavY*
this.countType=countTypes; 02NVdpo[wU
} DO+~
public void setCountId(int countIds){ ]:']
this.countId=countIds; +9pock
} [?qzMFb
public String getCountType(){ [kckE-y
return countType; vifw
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} X?&{<
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public int getCountId(){ _6`GHx
return countId; MA}}w&
} X%N!gy
} PBFpV8P,
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CountCache.java 6X?:mn'%QF
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/* ?UOaqcL
* CountCache.java {cO8q
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* ' u;Zw%O(J
* Created on 2007年1月1日, 下午5:01 @3=q9ftm
* yJ ljCu)f
* To change this template, choose Tools | Options and locate the template under Iu5 9W>
* the Source Creation and Management node. Right-click the template and choose 8t)gfSG
* Open. You can then make changes to the template in the Source Editor. :2/jI:L~
*/ .}Ys+d1b9c
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package com.tot.count; F#RN m5
import java.util.*; x2r.4
/** V}7)>i$A
* bhbTloCR
* @author t.VVE:A^%
*/ FKL@,>!<e
public class CountCache { wPu.hVz
public static LinkedList list=new LinkedList(); 0E,QOF{o
/** Creates a new instance of CountCache */ ;(;~yB|NZ5
public CountCache() {} TA:uB[Ji
public static void add(CountBean cb){ KhX)maQ
if(cb!=null){ fE&s 6w&
list.add(cb); nt-_)4Fm
} }aI>dHL
} P/^@t+KC
} HY?#r]Ryt
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CountControl.java v0=v1G*rvJ
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/* ~RwoktO
* CountThread.java ^8]7
* :F#^Q%-IS
* Created on 2007年1月1日, 下午4:57 Q-#<{' (
* #h
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* To change this template, choose Tools | Options and locate the template under \.p;
4V&
* the Source Creation and Management node. Right-click the template and choose LHu
* Open. You can then make changes to the template in the Source Editor. +Wy `X5v
*/ |:4?K*w",
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package com.tot.count; 1^V.L+0s]
import tot.db.DBUtils; Bg zq
import java.sql.*; kdx06'4o
/** DHuvHK0#
* S'w}Ir
* @author Y
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*/ bb\XZ~)F
public class CountControl{ 3 |LRb/|
private static long lastExecuteTime=0;//上次更新时间 8 4reyA
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 .3XiL=^~Qp
/** Creates a new instance of CountThread */ e8oAGh"
public CountControl() {} f&$;iE
public synchronized void executeUpdate(){ 4K dYiuz0`
Connection conn=null; >, 'guaa
PreparedStatement ps=null; =h
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try{ }Qe(6'l_
conn = DBUtils.getConnection(); K ;]dZ8
conn.setAutoCommit(false); + @|u8+
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); W/ WP }QM
for(int i=0;i<CountCache.list.size();i++){ !Fxn1Z,
CountBean cb=(CountBean)CountCache.list.getFirst(); +]NpcE'
CountCache.list.removeFirst();
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ps.setInt(1, cb.getCountId()); f7!48,(fB
ps.executeUpdate();⑴ % WXl*
//ps.addBatch();⑵ Kb;Pd!Q
} wgolgof
//int [] counts = ps.executeBatch();⑶ r&+C%
conn.commit(); gd#?rc*f<3
}catch(Exception e){ M8 \/[R\
e.printStackTrace(); v@8SMOe%
} finally{ a}|<*!4zUQ
try{ 9IrCu?n9b
if(ps!=null) { Mqk|H~l5c
ps.clearParameters(); M"{*))O\-c
ps.close(); tq@)J_7|
ps=null; ;mz#$"(
} -%P}LaC<
}catch(SQLException e){} h8Oj
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DBUtils.closeConnection(conn); .
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} ?p 4iXHE
} +Zr~mwM=x
public long getLast(){ 4KSq]S.
return lastExecuteTime; :[f[-F
}
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public void run(){ =3SJl1w1
long now = System.currentTimeMillis(); HkhZB^_V
if ((now - lastExecuteTime) > executeSep) { LjW32>B
//System.out.print("lastExecuteTime:"+lastExecuteTime); Y}s6__
//System.out.print(" now:"+now+"\n"); ,L~aa?Nb-
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); 8y_(Iu|:
lastExecuteTime=now; r|\{!;7
executeUpdate(); -e_TJA
} =5fY3%^b{
else{ 7IkEud
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); ht>/7.p]
} x>BFK@#
} ;#IrHR*Bk
} K7(k_4
//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 Q)M-f;O
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类写好了,下面是在JSP中如下调用。 w'$>E4\
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<% "$K]+0ryG<
CountBean cb=new CountBean(); T"C.>G'[B
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); 5WxNH}{
CountCache.add(cb); 5!$sQ@#}D
out.print(CountCache.list.size()+"<br>"); O0`ofFN
CountControl c=new CountControl(); M2d&7>N
c.run(); 'NfsAE
out.print(CountCache.list.size()+"<br>"); ~]?EV?T
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