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: m[5ed1+
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CountBean.java Tq6@
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/* wZ8LY;
* CountData.java `Q^Vm3h
* k/xNqN(
* Created on 2007年1月1日, 下午4:44 zHj_q%A
* KrECAc
* To change this template, choose Tools | Options and locate the template under @0:mP
* the Source Creation and Management node. Right-click the template and choose }>Lz\.Z/+[
* Open. You can then make changes to the template in the Source Editor. ku5g`ho
*/ "%t !+E>nr
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package com.tot.count;
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/** \AR3DDm
* 6dCqS
* @author r,Pu-bhF
*/ _`94CC:
public class CountBean { E }w<-]8
private String countType;
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int countId; 4gm(gY>[
/** Creates a new instance of CountData */ #KSB%
public CountBean() {} In4T`c?kQ
public void setCountType(String countTypes){ fI(H
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this.countType=countTypes; i
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} A7:W0Gg
public void setCountId(int countIds){ I."4u~[
this.countId=countIds; ~R
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} X"G3lG
public String getCountType(){ t#J
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return countType; p&\x*~6u
} `!T6#6h
public int getCountId(){ 785Y*.p
return countId; )6zwprH!
} HaamLu
} d3C*]|gQ
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CountCache.java T1b9Zqc)f
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/* esEOV$s}
* CountCache.java t\+vTvT)RE
* :!EOg4%i
* Created on 2007年1月1日, 下午5:01 WxLILh
* 4B8{\"6
* To change this template, choose Tools | Options and locate the template under pRdO4?l
* the Source Creation and Management node. Right-click the template and choose &"svt2
* Open. You can then make changes to the template in the Source Editor.
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*/ <tTn$<b
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package com.tot.count; eVWnD,'
import java.util.*; ]HP
/** PFIL)D
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* T%F8=kb-9
* @author [! :.9
*/ ~F]- +|
public class CountCache { G#0 4h{
public static LinkedList list=new LinkedList(); J`3pXc$.
/** Creates a new instance of CountCache */ 1k>*
public CountCache() {} F;&'C$%
public static void add(CountBean cb){ WYE[H9x1?
if(cb!=null){ 7"y"%+*/
list.add(cb); ]urcA,a
} N|1k6g=0
} :FdV$E]]<
} i_&&7.
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CountControl.java V9m1n=r
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/* r,b-c
* CountThread.java G>{;@u
* Rf\>bI<.
* Created on 2007年1月1日, 下午4:57 18!0Hl>
* B|~\m~
* To change this template, choose Tools | Options and locate the template under D`.CXFI+U
* the Source Creation and Management node. Right-click the template and choose NLF{W|X
* Open. You can then make changes to the template in the Source Editor. |^@TA=_
*/ o0Hh&:6!M
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package com.tot.count; EY!aiH6P
import tot.db.DBUtils; 8DLMxG
import java.sql.*; @,sg^KB
/** ?
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* 5,qfr!hN,
* @author &e%y|{Y
*/ Wm.SLr,o0
public class CountControl{ 4//Ww6W:
private static long lastExecuteTime=0;//上次更新时间 s 4}}MV3X
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 58MBG&a%
/** Creates a new instance of CountThread */ YKUs>tQ!
public CountControl() {} c66Iy"
public synchronized void executeUpdate(){ :/Nz' n
Connection conn=null; VxfFk4
PreparedStatement ps=null; GYv2^IB:
try{ c{#lKD<7
conn = DBUtils.getConnection(); eGLLh_V"
conn.setAutoCommit(false); KFC zf_P!
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); diqG8KaK
for(int i=0;i<CountCache.list.size();i++){ Qo{^jDe,c*
CountBean cb=(CountBean)CountCache.list.getFirst(); W?/7PVGv5h
CountCache.list.removeFirst(); s6). ?oE
ps.setInt(1, cb.getCountId()); \"PlM!0du
ps.executeUpdate();⑴ "$:nz}
//ps.addBatch();⑵ ^ tm,gh
} F1|4([-<]
//int [] counts = ps.executeBatch();⑶ P[ KJuc
conn.commit(); 8N8B${X
}catch(Exception e){
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e.printStackTrace(); r0j:ll d
} finally{ 3QS"n.d
try{ ;Fuxj!gF
if(ps!=null) { "v~w#\pz7
ps.clearParameters(); ZwF_hm=/[
ps.close(); 1rE hL
ps=null; @eT!v{o
} x%x:gkq
}catch(SQLException e){} hlkf|H
DBUtils.closeConnection(conn); .f&,~$e4
} I[<C)IG
} 35jP</
public long getLast(){ sOLo[5y'
return lastExecuteTime; R`>E_SY
} [N#2uo
public void run(){ Cg21-G.
long now = System.currentTimeMillis(); qdj,Qz9ly
if ((now - lastExecuteTime) > executeSep) { (g~&$&pa
//System.out.print("lastExecuteTime:"+lastExecuteTime); FJ>| l#nO
//System.out.print(" now:"+now+"\n"); -_pI:K[
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); m2<sVTN`^
lastExecuteTime=now; )X| uOg&|
executeUpdate(); w>VM--
} -oe&1RrdVg
else{ }N4=~'R
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); oOe5IczS(
} {My/+{eS!?
} r"U$udwjg
}
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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 D
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类写好了,下面是在JSP中如下调用。 Q} f=Ye(&}
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<% N9:xtrJ]_J
CountBean cb=new CountBean(); <(@m913|
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); )BS./zD*[<
CountCache.add(cb); "2 qp-'^[c
out.print(CountCache.list.size()+"<br>"); -jFt4Q7}8
CountControl c=new CountControl(); 7=mU["raz`
c.run(); |3\
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out.print(CountCache.list.size()+"<br>"); 0xC{Lf&
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