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: %1+~(1P
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CountBean.java SJ_cwYwI$
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/* 72.IhBNtT
* CountData.java DH*|>m&
* x9
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* Created on 2007年1月1日, 下午4:44 . pEeR
* g;Q^_4@
* To change this template, choose Tools | Options and locate the template under )7mJ+d[
* the Source Creation and Management node. Right-click the template and choose
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* Open. You can then make changes to the template in the Source Editor. T.N7`
*/ y:zT1I@>
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package com.tot.count; eZkz 1j~
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/** Jl9TMu!1]
* Lk+1r8
* @author \I{A33i2w
*/ aT1W]i
public class CountBean { BFu9KS+@)
private String countType; #IA(*oM
int countId; RWcQT`
/** Creates a new instance of CountData */ g' U^fN
public CountBean() {} O*CX@Ne
public void setCountType(String countTypes){ uKzz/Y{
this.countType=countTypes; 717m.t,x
} T0)y5
public void setCountId(int countIds){ +ANIm^@
this.countId=countIds; zQfxw?~A
} yC$7XSr=
public String getCountType(){ -T6%3>h
return countType; >{=RQgGy
} YAG3PWmD
public int getCountId(){ ADUI@#vk
return countId; ")buDU6_
} <4bo7XH
} .]l2)OlLQ
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CountCache.java D4-U[l+K>
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/*
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* CountCache.java 5-po>1g'
* y_r6T
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* Created on 2007年1月1日, 下午5:01 ts$UC $
* H<?yG->
* To change this template, choose Tools | Options and locate the template under 55KL^+-~
* the Source Creation and Management node. Right-click the template and choose `t2! M\)
* Open. You can then make changes to the template in the Source Editor. CU&,Kq@
*/ 9xp
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package com.tot.count; O:R{4Q*5
import java.util.*; $QnfpM%+=
/** ^:j:;\;
* <p
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* @author g5\B- 3{
*/ hY9u#3
public class CountCache { )ISTb
public static LinkedList list=new LinkedList(); h2<$L
/** Creates a new instance of CountCache */ 4(ZV\}j1
public CountCache() {} >GRuS\B
public static void add(CountBean cb){ E/ )+hK&
if(cb!=null){ 5E|2S_)G
list.add(cb); Z:Am\7 I
} F9hWB17u
} j(2T,WM
} [D\AVx&
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CountControl.java 06;{2&ju<
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/* ajr8tp'
* CountThread.java 4!|ar?Zy
* @SXgaWr
* Created on 2007年1月1日, 下午4:57 gH.^NO5\'
* =c4U%d2
* To change this template, choose Tools | Options and locate the template under J6P
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* the Source Creation and Management node. Right-click the template and choose [%Xfl7;Wh
* Open. You can then make changes to the template in the Source Editor. 9$i`B>C~
*/ ;& +75n
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package com.tot.count; cxdM!L; `
import tot.db.DBUtils; C3gz)!3
import java.sql.*; _=#mmZkq
/** | w -W=v
* H0 t1& :
* @author M?lr#}d
*/ B\yid@e
public class CountControl{ mD3#$E!A1
private static long lastExecuteTime=0;//上次更新时间 [8#l~
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private static long executeSep=60000;//定义更新间隔时间,单位毫秒 Qg=~n:j
/** Creates a new instance of CountThread */ .}s a2-
public CountControl() {} WH*&MIjAr/
public synchronized void executeUpdate(){ SF7
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Connection conn=null; v<W++X7z
PreparedStatement ps=null; ;<H2N0qJ(
try{ iL<O|' be
conn = DBUtils.getConnection(); I^=M>_s4
conn.setAutoCommit(false); "?-s
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ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); *uR'eXW
for(int i=0;i<CountCache.list.size();i++){ cB^lSmu5
CountBean cb=(CountBean)CountCache.list.getFirst(); Gx($q;8
CountCache.list.removeFirst(); l:HuG!
ps.setInt(1, cb.getCountId()); e+U o-CO
ps.executeUpdate();⑴ jT',+
//ps.addBatch();⑵ xH uyfQLk
} ipG+qj/=
//int [] counts = ps.executeBatch();⑶ ww,'n{_
conn.commit(); Ns(F%zkm
}catch(Exception e){ @}:(t{>;e7
e.printStackTrace(); J.d<5`7
} finally{ {rQ`#?J}^?
try{ 8wOPpdc
if(ps!=null) { wC~Uy%
ps.clearParameters(); _45"Z}Zx
ps.close(); C.O-iBVe#
ps=null; TzJN,]F!M
} PX]v"xf
}catch(SQLException e){} 2z:9^a/]Na
DBUtils.closeConnection(conn); 62) F
} v80e]M!
} PR0]:t)E
public long getLast(){ /<~IKVz\&
return lastExecuteTime; t*#T~3p
} J5wq}<8
public void run(){ 9L,T @#7
long now = System.currentTimeMillis(); qM'5cxe
if ((now - lastExecuteTime) > executeSep) { KMa?2cJH#
//System.out.print("lastExecuteTime:"+lastExecuteTime); .E(Ucnz/
//System.out.print(" now:"+now+"\n"); q=U=Y
n
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); hE${eJQ| U
lastExecuteTime=now; fqxMTTg@
executeUpdate(); ryPzq}#
} TQE_zOa:
else{ S3w? X
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); lUmaNZ
} CAfG3;
} :v`o="
} gueCP+a_
//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 L-yC 'C
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类写好了,下面是在JSP中如下调用。 u- ,=C/iU
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<% cVN|5Y
CountBean cb=new CountBean(); rnUe/HjH
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); :B
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CountCache.add(cb); }I"^WCyH
out.print(CountCache.list.size()+"<br>"); (Q&Z/Fe
CountControl c=new CountControl(); kq+L63fZ
c.run(); HUH=Y;
out.print(CountCache.list.size()+"<br>"); hz!.|U@,{<
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